Records |
Author |
Newsome, G.A.; Kavich, G.; Alvarez-Martin, A. |
Title |
Interface for reproducible, multishot direct analysis of solid-phase microextraction samples |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
92 |
Issue |
6 |
Pages |
4182-4186 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
An enclosed interface that joins a direct analysis in real time (DART) probe, solid-phase microextraction (SPME) fiber, and the inlet of a high-resolution mass spectrometer is described. Unlike other systems to couple SPME sampling to ambient mass spectrometry, the interface is able to perform discrete analyses on different areas of a single SPME fiber device for up to three technical replicate measurements of one sampling event. Inlet flow speed and desorption temperature are optimized, and reproducibility is demonstrated between replicate analyses on the same derivatized SPME fiber and with sequential fiber sampling events, yielding analyte measurement center of variance (CV) from 3 to 6%. Conditioning is also performed with the enclosed DART. The interface is a straightforward addition to commercially available technologies, and machine diagrams for custom components operated with SPME/DART/MS equipment are included. |
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Place of Publication |
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Language |
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Wos |
000526563900004 |
Publication Date |
2020-02-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
Call Number |
UA @ admin @ c:irua:181926 |
Serial |
8113 |
Permanent link to this record |
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Author |
Liu, Y.; Cánovas, R.; Crespo, G.A.; Cuartero, M. |
Title |
Thin-layer potentiometry for creatinine detection in undiluted human urine using ion-exchange membranes as barriers for charged interferences |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
92 |
Issue |
4 |
Pages |
3315-3323 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Herein, thin-layer potentiometry combined with ion-exchange membranes as barriers for charged interferences is demonstrated for the analytical detection of creatinine (CRE) in undiluted human urine. Briefly, CRE diffuses through an anion-exchange membrane (AEM) from a sample contained in one fluidic compartment to a second reservoir, containing the enzyme CRE deiminase. There, CRE reacts with the enzyme, and the formation of ammonium is dynamically monitored by potentiometric ammonium-selective electrodes. This analytical concept is integrated into a lab-on-a-chip microfluidic cell that allows for a high sample throughput and the operation under stop-flow mode, which allows CRE to passively diffuse across the AEM. Conveniently, positively charged species (i.e., potassium, sodium, and ammonium, among others) are repelled by the AEM and never reach the ammonium-selective electrodes; thus, possible interference in the response can be avoided. As a result, the dynamic potential response of the electrodes is entirely ascribed to the stoichiometric formation of ammonium. The new CRE biosensor exhibits a Nernstian slope, within a linear range of response from 1 to 50 mM CRE concentration. As expected, the response time (15–60 min) primarily depends on the CRE diffusion across the AEM. CRE analysis in urine samples displayed excellent results, without requiring sample pretreatment (before the introduction of the sample in the microfluidic chip) and with high compatibility with development into a potential point-of-care clinical tool. In an attempt to decrease the analysis time, the presented analytical methodology for CRE detection is translated into an all-solid-state platform, in which the enzyme is immobilized on the surface of the ammonium-selective electrode and with the AEM on top. While more work is necessary in this direction, the CRE sensor appears to be promising for CRE analysis in both urine and blood. |
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Wos |
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Publication Date |
2020-01-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
Call Number |
UA @ admin @ c:irua:184380 |
Serial |
8667 |
Permanent link to this record |
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Author |
Kummamuru, N.B.; Watson, G.; Ciocarlan, R.-G.; Verbruggen, S.W.; Cool, P.; Van Der Voort, P.; Perreault, P. |
Title |
Accelerated methane storage in clathrate hydrates using mesoporous (Organo-) silica materials |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Fuel |
Abbreviated Journal |
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Volume |
354 |
Issue |
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Pages |
129403-129418 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Methane (CH4) clathrate hydrates have gained much attention in the ever-growing search for novel energy storage methods; however, they are currently limited due to their poor water-to-hydrate conversions and slow formation kinetics. To surmount these bottlenecks, significant research has been centered on the design of novel methods (porous media). In this vein, the present work explores two hydrophobic mesoporous solids, an alkyl-grafted mesoporous silica (SBA-15 C8) and a periodic mesoporous organosilica (Ring-PMO), in their ability to promote CH4 clathrates. Both materials have shown to facilitate CH4 clathrate formation at mild operating conditions (6 MPa and 269–276 K). The study revealed that the maximal CH4 storage capacities are strongly linked to the critical/optimal quantity of water in the system which was determined to be at 130% and 200% of the pore volume for SBA-15 C8 and Ring-PMO, respectively. Up to 90% and 95% of the maximum water-to-hydrate conversions were achieved in 90 min at the lowest experimental temperature and critical water content for SBA-15 C8 and Ring-PMO, respectively. At these conditions, SBA-15 C8 and Ring-PMO showed a maximum gas uptake of 98.2 and 101.2 mmol CH4/mol H2O, respectively. Both the materials exhibited no chemical or morphological changes post-clathrate formations (characterized using FT-IR, N2 sorption, XRD, and TEM), inferring their viability as clathrate promoters for multiple cycles. An integrated multistep model was considered adequate for representing the hydrate crystallization kinetics and fits well with the experimental kinetic data with a low average absolute deviation in water-to-hydrate conversions among the three distinct kinetic models analyzed. Overall, the results from this study demonstrate hydrophobic porous materials as effective promoters of CH4 clathrates, which could make clathrate-based CH4 storage and transport technology industrially viable. |
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Wos |
001059413200001 |
Publication Date |
2023-08-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0016-2361 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.4 |
Times cited |
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Open Access |
Not_Open_Access: Available from 07.02.2024 |
Notes |
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Approved |
Most recent IF: 7.4; 2023 IF: 4.601 |
Call Number |
UA @ admin @ c:irua:197987 |
Serial |
8829 |
Permanent link to this record |
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Author |
Alvarado-Alvarado, A.A.; De Bock, A.; Ysebaert, T.; Belmans, B.; Denys, S. |
Title |
Modeling the hygrothermal behavior of green walls in Comsol Multiphysics® : validation against measurements in a climate chamber |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Building and environment |
Abbreviated Journal |
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Volume |
238 |
Issue |
|
Pages |
110377-12 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL); Energy and Materials in Infrastructure and Buildings |
Abstract |
Green walls (GW) can diminish building's surface temperature through shading, insulation, and evapotranspiration mechanisms. These can be analyzed by computer models that account for heat and mass transfer phenomena. However, most previous models were one-dimensional thermal simulations in which boundary conditions (BC), like convective moisture transport, were not or only partly considered. The present work proposes a more comprehensive way to predict GW's hygrothermal behavior by integrating a 3D multiphysics model that couples heat and moisture transport in Comsol Multiphysics®. The air cavity that usually separates the GW from the building was also considered. Heat sink terms were added to represent plants' transpiration and substrates' evaporation, considering the leaf area density (LAD) and substrate's water saturation (Sr). The model was validated against experiments where four green wall-test panels (GW-TPs) were evaluated in a climate chamber under steady-state conditions. This provides a much sounder approach for validation than what currently exists (r = 0.97; RMSE = 0.33 °C). The four GW-TPs decreased the masonry's surface temperature in the range of 0.89–1.14 °C (0.97 ± 0.11 SD °C). The average contribution of the evapotranspiration effect was 30%, whereas the contribution of the air cavity was 60.7 ± 0.09%. The temperature at the substrate's rear was reduced on average by 0.57 ± 0.15 SD °C. When solar radiation was considered as a BC, the GW-TPs decreased the building's surface temperature by 10 °C. Lastly, high values of LAD and Sr translated into increased temperature reduction values. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001001412600001 |
Publication Date |
2023-05-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0360-1323 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.4 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 7.4; 2023 IF: 4.053 |
Call Number |
UA @ admin @ c:irua:196467 |
Serial |
8899 |
Permanent link to this record |
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Author |
Slaets, J.; Loenders, B.; Bogaerts, A. |
Title |
Plasma-based dry reforming of CH4: Plasma effects vs. thermal conversion |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Fuel |
Abbreviated Journal |
Fuel |
Volume |
360 |
Issue |
|
Pages |
130650 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this work we evaluate the chemical kinetics of dry reforming of methane in warm plasmas (1000–4000 K) using modelling with a newly developed chemistry set, for a broad range of parameters (temperature, power density and CO2/CH4 ratio). We compare the model against thermodynamic equilibrium concentrations, serving as validation of the thermal chemical kinetics. Our model reveals that plasma-specific reactions (i.e., electron impact collisions) accelerate the kinetics compared to thermal conversion, rather than altering the overall kinetics pathways and intermediate products, for gas temperatures below 2000 K. For higher temperatures, the kinetics are dominated by heavy species collisions and are strictly thermal, with negligible influence of the electrons and ions on the overall kinetics. When studying the effects of different gas mixtures on the kinetics, we identify important intermediate species, side reactions and side products. The use of excess CO2 leads to H2O formation, at the expense of H2 formation, and the CO2 conversion itself is limited, only approaching full conversion near 4000 K. In contrast, full conversion of both reactants is only kinetically limited for mixtures with excess CH4, which also gives rise to the formation of C2H2, alongside syngas. Within the given parameter space, our model predicts the 30/70 ratio of CO2/CH4 to be the most optimal for syngas formation with a H2/CO ratio of 2. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001138077700001 |
Publication Date |
2023-12-15 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0016-2361 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.4 |
Times cited |
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Open Access |
Not_Open_Access |
Notes |
This research was supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 810182 – SCOPE ERC Synergy project), the Catalisti-ICON project BluePlasma (Project No. HBC.2022.0445), the FWO-SBO project PlasMaCatDESIGN (FWO Grant ID S001619N), the Independent Research Fund Denmark (Project No. 0217-00231B) and through long-term structural funding (Methusalem). The computational resources and services used in this work were provided by the HPC core facility CalcUA of the Universiteit Antwerpen, and VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government. We also thank Bart Wanten, Roel Michiels, Pepijn Heirman, Claudia Verheyen, dr. Senne Van Alphen, dr. Elise Vervloessem, dr. Kevin van ’t Veer, dr. Joshua Boothroyd, dr. Omar Biondo and dr. Eduardo Morais for their expertise and feedback regarding the kinetics scheme. |
Approved |
Most recent IF: 7.4; 2024 IF: 4.601 |
Call Number |
PLASMANT @ plasmant @c:irua:201669 |
Serial |
8973 |
Permanent link to this record |
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Author |
Alvarez-Martin, A.; Quanico, J.; Scovacricchi, T.; Avranovich Clerici, E.; Baggerman, G.; Janssens, K. |
Title |
Chemical mapping of the degradation of geranium lake in paint cross sections by MALDI-MSI |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Analytical chemistry |
Abbreviated Journal |
|
Volume |
95 |
Issue |
49 |
Pages |
18215-18223 |
Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS); Ecosphere |
Abstract |
Matrix assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) has become a powerful method to extract spatially resolved chemical information in complex materials. This study provides the first use of MALDI-MSI to define spatial–temporal changes in oil paints. Due to the highly heterogeneous nature of oil paints, the sample preparation had to be optimized to prevent molecules from delocalizing. Here, we present a new protocol for the layer-specific analysis of oil paint cross sections achieving a lateral resolution of 10 μm and without losing ionization efficiency due to topographic effects. The efficacy of this method was investigated in oil paint samples containing a mixture of two historic organic pigments, geranium lake and lead white, a mixture often employed in the work of painter Vincent Van Gogh. This methodology not only allows for spatial visualization of the molecules responsible for the pink hue of the paint but also helps to elucidate the chemical changes behind the discoloration of paintings with this composition. The results demonstrate that this approach provides valuable molecular compositional information about the degradation pathways of pigments in specific paint layers and their interaction with the binding medium and other paint components and with light over time. Since a spatial correlation between molecular species and the visual pattern of the discoloration pattern can be made, we expect that mass spectrometry imaging will become highly relevant in future degradation studies of many more historical pigments and paints. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001142876000001 |
Publication Date |
2023-11-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 7.4; 2023 IF: 6.32 |
Call Number |
UA @ admin @ c:irua:201644 |
Serial |
9007 |
Permanent link to this record |
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Author |
Steijlen, A.S.M.; Parrilla, M.; Van Echelpoel, R.; De Wael, K. |
Title |
Dual microfluidic sensor system for enriched electrochemical profiling and identification of illicit drugs on-site |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Analytical chemistry |
Abbreviated Journal |
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Volume |
96 |
Issue |
1 |
Pages |
590-598 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
Electrochemical sensors have emerged as a new analytical tool for illicit drug detection to facilitate ultrafast and accurate identification of suspicious compounds on-site. Drugs of abuse can be identified using their unique voltammetric fingerprint at a given pH. Today, the right buffer solution is manually selected based on drug appearance, and in some cases, a consecutive analysis in two different pH solutions is required. In this work, we present a disposable microfluidic multichannel sensor system that automatically records fingerprints in two pH solutions (e.g., pH 5 and pH 12). This system has two advantages. It will overcome the manual selection of a buffer solution at the right pH, decrease analysis time, and minimize the risk of human errors. Second, the combination of two fingerprints, the superfingerprint, contains more detailed information about the samples, which enhances the selectivity of the analytical technique. First, real-time pH measurements proved that the sample can be brought to the desired pH within a minute. Subsequently, an electrochemical study on the microfluidic platform with 1 mM illicit drug standards of MDMA, cocaine, heroin, and methamphetamine showed that the characteristic voltammetric fingerprints and peak potentials are reproducible, also in the presence of common cutting agents. Finally, the microfluidic concept was validated with real confiscated samples, showing promising results for the user-friendly identification of drugs of abuse. In short, this paper presents a successful proof-of-concept study of a multichannel microfluidic sensor system to enrich the fingerprints of illicit drugs at pH 5 and pH 12, thus providing a low-cost, portable, and rapid identification system of illicit drugs with minimal user intervention. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001139443500001 |
Publication Date |
2023-12-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.4 |
Times cited |
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Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: 7.4; 2024 IF: 6.32 |
Call Number |
UA @ admin @ c:irua:201877 |
Serial |
9024 |
Permanent link to this record |
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Author |
De Bock, A.; Belmans, B.; Vanlanduit, S.; Blom, J.; Alvarado Alvarado, A.A.; Audenaert, A. |
Title |
A review on the leaf area index (LAI) in vertical greening systems |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Building and environment |
Abbreviated Journal |
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Volume |
229 |
Issue |
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Pages |
109926-14 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL); Sustainable Pavements and Asphalt Research (SuPAR); Energy and Materials in Infrastructure and Buildings |
Abstract |
The leaf area index (LAI) is a key dynamic parameter in Vertical Greening Systems (VGS). It quantifies the total amount of leaf area in the canopy and largely determines the extent of co-benefits of VGS. Whereas many studies on VGS discuss the importance of the LAI, only few elaborate on the parameter itself, how it is determined and what the current limitations are in VGS. Moreover, although there is scientific consensus on the importance of LAI in VGS, specific non-destructive monitoring techniques for continuous LAI monitoring appear to be absent, which results in limited overall data on the LAI of VGS under different spatial and temporal conditions and problems in quantifying the benefits of VGS in practice. To fill these gaps, this paper specifically focuses on the LAI of VGS and its monitoring techniques. An overview of existing LAI monitoring techniques in the field of VGS is presented. To arrive at dedicated techniques, this is complemented by a thorough analysis of LAI monitoring techniques used in other research fields, e.g. agriculture and forestry. It is established that two indirect techniques for LAI monitoring are currently available in the VGS sector, but a proper standardized sampling methodology currently lacks. Monitoring techniques used in other sectors offer opportunities for developing dedicated monitoring methods for VGS, but require further research due to the specific features of VGS systems. Furthermore, guidelines are proposed for a more standardized LAI determination of reporting of LAI values in VGS. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000950866100001 |
Publication Date |
2022-12-19 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0360-1323 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 7.4; 2023 IF: 4.053 |
Call Number |
UA @ admin @ c:irua:194575 |
Serial |
9085 |
Permanent link to this record |
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Author |
Janssens, K.; Alfeld, M.; van der Snickt, G.; de Nolf, W.; Vanmeert, F.; Radepont, M.; Monico, L.; et al. |
Title |
The use of synchrotron radiation for the characterization of artists' pigments and paintings |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Annual review of analytical chemistry |
Abbreviated Journal |
Annu Rev Anal Chem |
Volume |
6 |
Issue |
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Pages |
399-425 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
We review methods and recent studies in which macroscopic to (sub)microscopic X-ray beams were used for nondestructive analysis and characterization of pigments, paint microsamples, and/or entire paintings. We discuss the use of portable laboratory- and synchrotron-based instrumentation and describe several variants of X-ray fluorescence (XRF) analysis used for elemental analysis and imaging and combined with X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Macroscopic and microscopic (μ-)XRF variants of this method are suitable for visualizing the elemental distribution of key elements in paint multilayers. Technical innovations such as multielement, large-area XRF detectors have enabled such developments. The use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that take place during natural pigment alteration processes. However, synchrotron-based combinations of μ-XRF, μ-XAS, and μ-XRD are suitable for such studies. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000323887500019 |
Publication Date |
2013-06-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-1327 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.435 |
Times cited |
46 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 7.435; 2013 IF: 7.814 |
Call Number |
UA @ admin @ c:irua:111315 |
Serial |
5902 |
Permanent link to this record |
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Author |
Cheng, X.; Xu, W.; Wen, H.; Zhang, J.; Zhang, H.; Li, H.; Peeters, F.M.; Chen, Q. |
Title |
Electronic properties of 2H-stacking bilayer MoS₂ measured by terahertz time-domain spectroscopy |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Frontiers of physics |
Abbreviated Journal |
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Volume |
18 |
Issue |
5 |
Pages |
53303-53311 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Bilayer (BL) molybdenum disulfide (MoS2) is one of the most important electronic structures not only in valleytronics but also in realizing twistronic systems on the basis of the topological mosaics in moire superlattices. In this work, BL MoS2 on sapphire substrate with 2H-stacking structure is fabricated. We apply the terahertz (THz) time-domain spectroscopy (TDS) for examining the basic optoelectronic properties of this kind of BL MoS2. The optical conductivity of BL MoS2 is obtained in temperature regime from 80 K to 280 K. Through fitting the experimental data with the theoretical formula, the key sample parameters of BL MoS2 can be determined, such as the electron density, the electronic relaxation time and the electronic localization factor. The temperature dependence of these parameters is examined and analyzed. We find that, similar to monolayer (ML) MoS2, BL MoS2 with 2H-stacking can respond strongly to THz radiation field and show semiconductor-like optoelectronic features. The theoretical calculations using density functional theory (DFT) can help us to further understand why the THz optoelectronic properties of BL MoS2 differ from those observed for ML MoS2. The results obtained from this study indicate that the THz TDS can be applied suitably to study the optoelectronic properties of BL MoS2 based twistronic systems for novel applications as optical and optoelectronic materials and devices. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000991955300002 |
Publication Date |
2023-05-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2095-0462; 2095-0470 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.5 |
Times cited |
3 |
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 7.5; 2023 IF: 2.579 |
Call Number |
UA @ admin @ c:irua:197398 |
Serial |
8818 |
Permanent link to this record |
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Author |
Zeng, Y.-J.; Schouteden, K.; Amini, M.N.; Ruan, S.-C.; Lu, Y.-F.; Ye, Z.-Z.; Partoens, B.; Lamoen, D.; Van Haesendonck, C. |
Title |
Electronic band structures and native point defects of ultrafine ZnO nanocrystals |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
7 |
Issue |
7 |
Pages |
10617-10622 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
Ultrafine ZnO nanocrystals with a thickness down to 0.25 nm are grown by a metalorganic chemical vapor deposition method. Electronic band structures and native point defects of ZnO nanocrystals are studied by a combination of scanning tunneling microscopy/spectroscopy and first-principles density functional theory calculations. Below a critical thickness of nm ZnO adopts a graphitic-like structure and exhibits a wide band gap similar to its wurtzite counterpart. The hexagonal wurtzite structure, with a well-developed band gap evident from scanning tunneling spectroscopy, is established for a thickness starting from similar to 1.4 nm. With further increase of the thickness to 2 nm, V-O-V-Zn defect pairs are easily produced in ZnO nanocrystals due to the self-compensation effect in highly doped semiconductors. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000355055000063 |
Publication Date |
2015-04-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244;1944-8252; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
15 |
Open Access |
|
Notes |
Hercules; EWI |
Approved |
Most recent IF: 7.504; 2015 IF: 6.723 |
Call Number |
c:irua:126408 |
Serial |
999 |
Permanent link to this record |
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|
Author |
Buffière, M.; Brammertz, G.; Sahayaraj, S.; Batuk, M.; Khelifi, S.; Mangin, D.; El Mel, A.A.; Arzel, L.; Hadermann, J.; Meuris, M.; Poortmans, J.; |
Title |
KCN chemical etch for interface engineering in Cu2ZnSnSe4 solar cells |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
7 |
Issue |
7 |
Pages |
14690-14698 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The removal of secondary phases from the surface of the kesterite crystals is one of the major challenges to improve the performances of Cu2ZnSn(S,Se)(4) (CZTSSe) thin film solar cells. In this Contribution, the KCN/KOH Chemical etching approach, originally developed for the removal of CuxSe phases in Cu(In,Ga)(S,Se)(2) thin films) is applied to CZTSe absorbers exhibiting various chemical compositions. Two distinct electrical behaviors were observed on CZTSe/CdS solar cells after treatment: (i) the improvement of the fill factor (FF) after 30 s of etching for the CZTSe absorbers showing initially a distortion of the electrical characteristic; (ii) the progressive degradation Of the FF after long treatment time for all Cu-poor CZTSe solar cell samples. The first effect can be attributed to the action of KCN on the absorber, that is found to clean the absorber free surface from most of the secondary phases surrounding the kesterite grains (e.g., Se-0, CuxSe, SnSex, SnO2, Cu2SnSe3 phases, excepting the ZnSe-based phases). The second observation was identified as a consequence of the preferential etching of Se, Sn, and Zn from the CZTSe surface by the KOH solution, combined with the modification of the alkali content of the absorber. The formation of a Cu-rich shell at the absorber/buffer layer interface, leading to the increase of the recombination rate at the interface, and the increase in the doping of the absorber layer after etching are found to be at the origin of the deterioration of the FF of the solar cells. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000358395200019 |
Publication Date |
2015-06-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244;1944-8252; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
34 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 7.504; 2015 IF: 6.723 |
Call Number |
c:irua:127153 |
Serial |
1755 |
Permanent link to this record |
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|
Author |
Li, D.Y.; Zeng, Y.J.; Batuk, D.; Pereira, L.M.C.; Ye, Z.Z.; Fleischmann, C.; Menghini, M.; Nikitenko, S.; Hadermann, J.; Temst, K.; Vantomme, A.; Van Bael, M.J.; Locquet, J.P.; Van Haesendonck, C.; |
Title |
Relaxor ferroelectricity and magnetoelectric coupling in ZnOCo nanocomposite thin films : beyond multiferroic composites |
Type |
A1 Journal article |
Year |
2014 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
6 |
Issue |
7 |
Pages |
4737-4742 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
ZnOCo nanocomposite thin films are synthesized by combination of pulsed laser deposition of ZnO and Co ion implantation. Both superparamagnetism and relaxor ferroelectricity as well as magnetoelectric coupling in the nanocomposites have been demonstrated. The unexpected relaxor ferroelectricity is believed to be the result of the local lattice distortion induced by the incorporation of the Co nanoparticles. Magnetoelectric coupling can be attributed to the interaction between the electric dipole moments and the magnetic moments, which are both induced by the incorporation of Co. The introduced ZnOCo nanocomposite thin films are different from conventional strain-mediated multiferroic composites. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000334572800018 |
Publication Date |
2014-03-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244;1944-8252; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
21 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 7.504; 2014 IF: 6.723 |
Call Number |
UA @ lucian @ c:irua:117063 |
Serial |
2864 |
Permanent link to this record |
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|
|
Author |
Zeng, Y.-J.; Gauquelin, N.; Li, D.-Y.; Ruan, S.-C.; He, H.-P.; Egoavil, R.; Ye, Z.-Z.; Verbeeck, J.; Hadermann, J.; Van Bael, M.J.; Van Haesendonck, C. |
Title |
Co-Rich ZnCoO Nanoparticles Embedded in Wurtzite Zn1-xCoxO Thin Films: Possible Origin of Superconductivity |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
7 |
Issue |
7 |
Pages |
22166-22171 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Co-rich ZnCoO nanoparticles embedded in wurtzite Zn0.7Co0.3O thin films are grown by pulsed laser deposition on a Si substrate. Local superconductivity with an onset Tc at 5.9 K is demonstrated in the hybrid system. The unexpected superconductivity probably results from Co(3+) in the Co-rich ZnCoO nanoparticles or from the interface between the Co-rich nanoparticles and the Zn0.7Co0.3O matrix. |
Address |
Solid State Physics and Magnetism Section, KU Leuven , Celestijnenlaan 200 D, BE-3001 Leuven, Belgium |
Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
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Editor |
|
Language |
English |
Wos |
000363001500007 |
Publication Date |
2015-09-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244;1944-8252; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
13 |
Open Access |
|
Notes |
This work has been supported by the Research Foundation − Flanders (FWO, Belgium) as well as by the Flemish Concerted Research Action program (BOF KU Leuven, GOA/14/007). N. G. and J. V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The Qu-Ant-EM microscope was partly funded by the Flemish Hercules Foundation. The work at Shenzhen University was supported by National Natural Science Foundation of China under Grant No. 61275144 and Natural Science Foundation of SZU. Y.-J. Z. acknowledges funding under grant No. SKL2015-12 from the State Key Laboratory of Silicon Materials; ECASJO_; |
Approved |
Most recent IF: 7.504; 2015 IF: 6.723 |
Call Number |
c:irua:129195 c:irua:129195UA @ admin @ c:irua:129195 |
Serial |
3949 |
Permanent link to this record |
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|
|
Author |
Warwick, M.E.A.; Kaunisto, K.; Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Bontempi, E.; Sada, C.; Ruoko, T.P.; Turner, S.; Van Tendeloo, G.; |
Title |
Vapor phase processing of \alpha-Fe2O3 photoelectrodes for water splitting : an insight into the structure/property interplay |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
7 |
Issue |
7 |
Pages |
8667-8676 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Harvesting radiant energy to trigger water photoelectrolysis and produce clean hydrogen is receiving increasing attention in the search of alternative energy resources. In this regard, hematite (alpha-Fe2O3) nanostructures with controlled nano-organization have been fabricated and investigated for use as anodes in photoelectrochemical (PEC) cells. The target systems have been grown on conductive substrates by plasma enhanced-chemical vapor deposition (PE-CVD) and subjected to eventual ex situ annealing in air to further tailor their structure and properties. A detailed multitechnique approach has enabled to elucidate between system characteristics and the generated photocurrent. The present alpha-Fe2O3 systems are characterized by a high purity and hierarchical morphologies consisting of nanopyramids/organized dendrites, offering a high contact area with the electrolyte. PEC data reveal a dramatic response enhancement upon thermal treatment, related to a more efficient electron transfer. The reasons underlying such a phenomenon are elucidated and discussed by transient absorption spectroscopy (TAS) studies of photogenerated charge carrier kinetics, investigated on different time scales for the first time on PE-CVD Fe2O3 nanostructures. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000353931300037 |
Publication Date |
2015-04-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244;1944-8252; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
51 |
Open Access |
|
Notes |
246791 Countatoms; Fwo |
Approved |
Most recent IF: 7.504; 2015 IF: 6.723 |
Call Number |
c:irua:126059 |
Serial |
3836 |
Permanent link to this record |
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|
Author |
Schrittwieser, S.; Pelaz, B.; Parak, W.J.; Lentijo-Mozo, S.; Soulantica, K.; Dieckhoff, J.; Ludwig, F.; Altantzis, T.; Bals, S.; Schotter, J. |
Title |
Homogeneous Protein Analysis by Magnetic Core-Shell Nanorod Probes |
Type |
A1 Journal article |
Year |
2016 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
8 |
Issue |
8 |
Pages |
8893-8899 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Studying protein interactions is of vital importance both to fundamental biology research and to medical applications. Here, we report on the experimental proof of a universally applicable label-free homogeneous platform for rapid protein analysis. It is based on optically detecting changes in the rotational dynamics of magnetically agitated core-shell nanorods upon their specific interaction with proteins. By adjusting the excitation frequency, we are able to optimize the measurement signal for each analyte protein size. In addition, due to the locking of the optical signal to the magnetic excitation frequency, background signals are suppressed, thus allowing exclusive studies of processes at the nanoprobe surface only. We study target proteins (soluble domain of the human epidermal growth factor receptor 2 – sHER2) specifically binding to antibodies (trastuzumab) immobilized on the surface of our nanoprobes and demonstrate direct deduction of their respective sizes. Additionally, we examine the dependence of our measurement signal on the concentration of the analyte protein, and deduce a minimally detectable sHER2 concentration of 440 pM. For our homogeneous measurement platform, good dispersion stability of the applied nanoprobes under physiological conditions is of vital importance. To that end, we support our measurement data by theoretical modeling of the total particle-particle interaction energies. The successful implementation of our platform offers scope for applications in biomarker-based diagnostics as well as for answering basic biology questions. |
Address |
Molecular Diagnostics, AIT Austrian Institute of Technology , Vienna, Austria |
Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
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Editor |
|
Language |
English |
Wos |
000374274900007 |
Publication Date |
2016-03-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
16 |
Open Access |
OpenAccess |
Notes |
The authors thank Frauke Alves, Julia Bode and Fernanda Ramos Gomes from the Max-Planck-Institute of Experimental Medicine in Göttingen for providing the trastuzumab antibody in form of the Herceptin therapeutic drug. The figure showing the measurement principle has been created by Darragh Crotty (www.darraghcrotty.com). Parts of this research were supported by the European Commission FP7 NAMDIATREAM project (EU NMP4-LA-2010−246479), by the German research foundation (DFG grant GRK 1782 to W.J.P.), and by the European Research Council (ERC Starting Grant #335078 Colouratom). B.P. acknowledges a PostDoctoral fellowship from the Alexander von Humboldt foundation. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ; ECAS_Sara; |
Approved |
Most recent IF: 7.504 |
Call Number |
c:irua:132889 |
Serial |
4059 |
Permanent link to this record |
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|
Author |
Ao, Z.; Jiang, Q.; Li, S.; Liu, H.; Peeters, F.M.; Li, S.; Wang, G. |
Title |
Enhancement of the stability of fluorine atoms on defective graphene and at graphene/fluorographene interface |
Type |
A1 Journal article |
Year |
2015 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
7 |
Issue |
7 |
Pages |
19659-19665 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Fluorinated graphene is one of the most important derivatives of graphene and has been found to have great potential in optoelectronic and photonic nanodevices. However, the stability of F atoms on fluorinated graphene under different conditions, which is essential to maintain the desired properties of fluorinated graphene, is still unclear. In this work, we investigate the diffusion of F atoms on pristine graphene, graphene with defects, and at graphene/fluorographene interfaces by using density functional theory calculations. We find that an isolated F atom diffuses easily on graphene, but those F atoms can be localized by inducing vacancies or absorbates in graphene and by creating graphene/fluorographene interfaces, which would strengthen the binding energy of F atoms on graphene and increase the diffusion energy barrier of F atoms remarkably. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000361252400018 |
Publication Date |
2015-08-24 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
35 |
Open Access |
|
Notes |
; We acknowledge the financial supports from the Chancellor's Research Fellowship Program of the University of Technology Sydney, the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish Government. This research was also supported by the National Computational Infrastructure (NCI) through the merit allocation scheme and used the NCI resources and facilities in Canberra, Australia. ; |
Approved |
Most recent IF: 7.504; 2015 IF: 6.723 |
Call Number |
UA @ lucian @ c:irua:128703 |
Serial |
4177 |
Permanent link to this record |
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|
Author |
Conings, B.; Bretschneider, S.A.; Babayigit, A.; Gauquelin, N.; Cardinaletti, I.; Manca, J.V.; Verbeeck, J.; Snaith, H.J.; Boyen, H.-G. |
Title |
Structure-property relations of methylamine vapor treated hybrid perovskite CH3NH3PbI3 films and solar cells |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
9 |
Issue |
9 |
Pages |
8092-8099 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The power conversion efficiency of halide perovskite solar cells is heavily dependent on the perovskite layer being sufficiently smooth and pinhole-free. It has been shown that these features can be obtained even when starting out from rough and discontinuous perovskite film, by briefly exposing it to methylamine (MA) vapor. The exact underlying physical mechanisms of this phenomenon are, however, still unclear. By investigating smooth, MA treated films, based on very rough and discontinuous reference films of methylammonium triiode (MAPbI3), considering their morphology, crystalline features, local conductive properties, and charge carrier lifetime, we unravel the relation between their characteristic physical qualities and their performance in corresponding solar cells. We discover that the extensive improvement in photovoltaic performance upon MA treatment is a consequence of the induced morphological enhancement of the perovskite layer, together with improved electron injection into TiO2, which in fact compensates for an otherwise compromised bulk electronic quality, simultaneously caused by the MA treatment. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000396186000025 |
Publication Date |
2017-02-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
43 |
Open Access |
OpenAccess |
Notes |
This work was financially supported by BOF (Hasselt University) and the Research Fund Flanders (FWO). B.C. is a postdoctoral research fellow of the FWO. A.B. is financially supported by FWO and Imec. J.V. and N.G. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and FWO project G.0044.13N “Charge ordering”. The Qu-Ant-EM microscope used for this study was partly funded by the Hercules fund from the Flemish Government. The authors thank Tim Vangerven for Urbach energy determination, and Johnny Baccus and Jan Mertens for technical support. |
Approved |
Most recent IF: 7.504 |
Call Number |
EMAT @ emat @ c:irua:140849 |
Serial |
4422 |
Permanent link to this record |
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|
Author |
Ustarroz, J.; Geboes, B.; Vanrompay, H.; Sentosun, K.; Bals, S.; Breugelmans, T.; Hubin, A. |
Title |
Electrodeposition of Highly Porous Pt Nanoparticles Studied by Quantitative 3D Electron Tomography: Influence of Growth Mechanisms and Potential Cycling on the Active Surface Area |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
9 |
Issue |
9 |
Pages |
16168-16177 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
Nanoporous Pt nanoparticles (NPs) are promising fuel cell catalysts due to their large surface area and increased electrocatalytic activity towards the oxygen reduction reaction (ORR). Herein, we report on the infuence of the growth mechanisms on the surface properties of electrodeposited Pt dendritic NPs with large surface areas. The electrochemically active surface was studied by hydrogen underpotential deposition (HUPD) and compared for the rst time to high angle annular dark eld scanning transmission electron microscopy (HAADF-STEM) quantitative 3D electron tomography of individual nanoparticles. Large nucleation overpotential leads to a large surface coverage of Pt roughened spheroids, which provide large roughness factor (Rf ) but low mass-specic electrochemically active surface area (EASA). Lowering the nucleation overpotential leads to highly porous Pt NPs with pores protruding to the center of the structure. At the expense of smaller Rf , the obtained EASA values of these structures are in the range of these of large surface area supported fuel cell catalysts. The active surface area of the Pt dendritic NPs was measured by electron tomography and it was found that the potential cycling in the H adsorption/desorption and Pt oxidation/reduction region, which is generally performed to determine the EASA, leads to a signicant reduction of that surface area due to a partial collapse of their dendritic and porous morphology. Interestingly, the extrapolation of the microscopic tomography results to macroscopic electrochemical parameters indicated that the surface properties measured by H UPD are comparable to the values measured on individual NPs by electron tomography after the degradation caused by the H UPD measurement. These results highlight that the combination of electrochemical and quantitative 3D surface analysis techniques is essential to provide insights into the surface properties, the electrochemical stability and, hence, the applicability of these materials. Moreover, it indicates that care must be taken with widely used electrochemical methods of surface area determination, especially in the case of large surface area and possibly unstable nanostructures, since the measured surface can be strongly aected by the measurement itself. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000401782500028 |
Publication Date |
2017-04-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
24 |
Open Access |
OpenAccess |
Notes |
Jon Ustarroz acknowledges funding from the Fonds Wetenschappelijk Onderzoek in Flanders (FWO, postdoctoral grant 12I7816N). S. Bals acknowledges funding from the European Research Council (Starting Grant No. COLOURATOMS 335078). S.B. and T.B. acknowledge the University of Antwerp for nancial support in the frame of a GOA project. H.V. gratefully acknowledges nancial support by the Flemish Fund for Scientic Research (FWO Vlaanderen). All the authors acknowledge Laurens Stevaert for his contribution to the work presented in this manuscript. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara |
Approved |
Most recent IF: 7.504 |
Call Number |
EMAT @ emat @ c:irua:142345UA @ admin @ c:irua:142345 |
Serial |
4552 |
Permanent link to this record |
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Author |
Kurttepeli, M.; Deng, S.; Mattelaer, F.; Cott, D.J.; Vereecken, P.; Dendooven, J.; Detavernier, C.; Bals, S. |
Title |
Heterogeneous TiO2/V2O5/Carbon Nanotube Electrodes for Lithium-Ion Batteries |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
9 |
Issue |
9 |
Pages |
8055-8064 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Vanadium pentoxide (V2O5) is proposed and investigated as a cathode material for lithium-ion (Li-ion) batteries. However, the dissolution of V2O5 during the charge/discharge remains as an issue at the V2O5–electrolyte interface. In this work, we present a heterogeneous nanostructure with carbon nanotubes supported V2O5/titanium dioxide (TiO2) multilayers as electrodes for thin-film Li-ion batteries. Atomic layer deposition of V2O5 on carbon nanotubes provides enhanced Li storage capacity and high rate performance. An additional TiO2 layer leads to increased morphological stability and in return higher electrochemical cycling performance of V2O5/carbon nanotubes. The physical and chemical properties of TiO2/V2O5/carbon nanotubes are characterized by cyclic voltammetry and charge/discharge measurements as well as electron microscopy. The detailed mechanism of the protective TiO2 layer to improve the electrochemical cycling stability of the V2O5 is unveiled. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000396186000021 |
Publication Date |
2017-03-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
28 |
Open Access |
OpenAccess |
Notes |
European Research Council, 239865 335078 ; Fonds Wetenschappelijk Onderzoek; Agentschap voor Innovatie door Wetenschap en Technologie, 18142 ; Bijzonder Onderzoeksfonds, GOA – 01G01513 ; This research was funded by the Flemish research foundation FWO-Vlaanderen, by the European Research Council (Starting Grant No. 239865 and No. 335078), by IWT-Flanders (SBO project IWT 18142 “SoS-Lion”) and by the Special Research Fund BOF of Ghent University (GOA – 01G01513); colouratoms (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara |
Approved |
Most recent IF: 7.504 |
Call Number |
EMAT @ emat @ c:irua:142446UA @ admin @ c:irua:142446 |
Serial |
4572 |
Permanent link to this record |
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Author |
Tran, T.L.A.; Çakir, D.; Wong, P.K.J.; Preobrajenski, A.B.; Brocks, G.; van der Wiel, W.G.; de Jong, M.P. |
Title |
Magnetic properties of bcc-Fe(001)/C-60 interfaces for organic spintronics |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Acs Applied Materials & Interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
5 |
Issue |
3 |
Pages |
837-841 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The magnetic structure of the interfaces between organic semiconductors and ferromagnetic contacts plays a key role in the spin injection and extraction processes in organic spintronic devices. We present a combined computational (density functional theory) and experimental (X-ray magnetic circular dichroism) study on the magnetic properties of interfaces between bcc-Fe(001) and C-60 molecules. C-60 is an interesting candidate for application in organic spintronics due to the absence of hydrogen atoms and the associated hyperfine fields. Adsorption of C-60 on Fe(001) reduces the magnetic moments on the top Fe layers by similar to 6%, while inducing an antiparrallel magnetic moment of similar to-0.2 mu(B) on C-60. Adsorption of C-60 on a model ferromagnetic substrate consisting of three Fe monolayers on W(001) leads to a different structure but to very similar interface magnetic properties. |
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Wos |
000315079700050 |
Publication Date |
2013-01-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
28 |
Open Access |
|
Notes |
; The authors acknowledge support from the European project MINOTOR (Grant No. FP7-NMP-228424), the European Research Council (ERC Starting Grant No. 280020), and the NWO VIDI program (Grant No. 10246). The use of supercomputer facilities was sponsored by the “Stichting Nationale Computerfaciliteiten (NCF)”, financially supported by the “Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)”. ; |
Approved |
Most recent IF: 7.504; 2013 IF: 5.900 |
Call Number |
UA @ lucian @ c:irua:128326 |
Serial |
4599 |
Permanent link to this record |
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Author |
Pullini, D.; Sgroi, M.; Mahmoud, A.; Gauquelin, N.; Maschio, L.; Lorenzo-Ferrari, A.M.; Groenen, R.; Damen, C.; Rijnders, G.; van den Bos, K.H.W.; Van Aert, S.; Verbeeck, J. |
Title |
One step toward a new generation of C-MOS compatible oxide p-n junctions: Structure of the LSMO/ZnO interface elucidated by an experimental and theoretical synergic work |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
9 |
Issue |
9 |
Pages |
20974-20980 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Heterostructures formed by La0.7Sr0.3MnO3/ZnO (LSMO/ZnO) interfaces exhibit extremely interesting electronic properties making them promising candidates for novel oxide p–n junctions, with multifunctional features. In this work, the structure of the interface is studied through a combined experimental/theoretical approach. Heterostructures were grown epitaxially and homogeneously on 4″ silicon wafers, characterized by advanced electron microscopy imaging and spectroscopy and simulated by ab initio density functional theory calculations. The simulation results suggest that the most stable interface configuration is composed of the (001) face of LSMO, with the LaO planes exposed, in contact with the (112̅0) face of ZnO. The ab initio predictions agree well with experimental high-angle annular dark field scanning transmission electron microscopy images and confirm the validity of the suggested structural model. Electron energy loss spectroscopy confirms the atomic sharpness of the interface. From statistical parameter estimation theory, it has been found that the distances between the interfacial planes are displaced from the respective ones of the bulk material. This can be ascribed to the strain induced by the mismatch between the lattices of the two materials employed |
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Wos |
000404090000079 |
Publication Date |
2017-05-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
4 |
Open Access |
OpenAccess |
Notes |
Financial support is acknowledged from the European Commission – DG research and innovation to the collaborative research project named Interfacing oxides (IFOX, Contract No. NMP3-LA-2010-246102). N.G. and J.V. acknowledge the European Union (EU) Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX for support. S.V.A. and K.H.W.B. acknowledge financial support from the Research Foundation Flanders through project fundings (G.0374.13N , G.0368.15N, and G.0369.15N) and a Ph.D. research grant to K.H.W.B. The microscope was partly funded by the Hercules Fund from the Flemish Government. The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. CINECA is acknowledged for computational facilities (Iscra project HP10CMO1UP). |
Approved |
Most recent IF: 7.504 |
Call Number |
EMAT @ emat @ c:irua:144431UA @ admin @ c:irua:144431 |
Serial |
4621 |
Permanent link to this record |
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Author |
Lu, A.K.A.; Houssa, M.; Radu, I.P.; Pourtois, G. |
Title |
Toward an understanding of the electric field-induced electrostatic doping in van der Waals heterostructures : a first-principles study |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
9 |
Issue |
8 |
Pages |
7725-7734 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Since the discovery of graphene, a broad range of two-dimensional (2D) materials has captured the attention of the scientific communities. Materials, such as hexagonal boron nitride (hBN) and the transition metal dichalcogenides (TMDs) family, have shown promising semiconducting and insulating properties that are very appealing for the semiconductor industry. Recently, the possibility of taking advantage of the properties of 2D-based heterostructures has been investigated for low-power nanoelectronic applications. In this work, we aim at evaluating the relation between the nature of the materials used in such heterostructures and the amplitude of the layer-to-layer charge transfer induced by an external electric field, as is typically present in nanoelectronic gated devices. A broad range of combinations of TMDs, graphene, and hBN has been investigated using density functional theory. Our results show that the electric field induced charge transfer strongly depends on the nature of the 2D materials used in the van der Waals heterostructures and to a lesser extent on the relative orientation of the materials in the structure. Our findings contribute to the building of the fundamental understanding required to engineer electrostatically the doping of 2D materials and to establish the factors that drive the charge transfer mechanisms in electron tunneling-based devices. These are key ingredients for the development of 2D -based nanoelectronic devices. |
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Place of Publication |
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Wos |
000395494200119 |
Publication Date |
2017-02-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
10 |
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 7.504 |
Call Number |
UA @ lucian @ c:irua:142483 |
Serial |
4696 |
Permanent link to this record |
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Author |
Ren, X.-N.; Hu, Z.-Y.; Jin, J.; Wu, L.; Wang, C.; Liu, J.; Liu, F.; Wu, M.; Li, Y.; Van Tendeloo, G.; Su, B.-L. |
Title |
Cocatalyzing Pt/PtO phase-junction nanodots on hierarchically porous TiO2 for highly enhanced photocatalytic hydrogen production |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
9 |
Issue |
35 |
Pages |
29687-29698 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Phase-junctions. between a cocatalyst and its semiconductor host are quite effective to enhance the photo catalytic activity and are widely studied, while reports on the phase-juncted cocatalyst are still rare. In this work, we report the deposition of the Pt/PtO phase-juncted nanodots as cocatalyst via NaOH modification of an interconnected meso-macroporous TiO2 network with high surface area and inner-particle mesopores to enhance the performance of photocatalytic H-2 production. Our results show that NaOH modification can largely influence Pt/PtO phase-juncted nanodot formation and dispersity. Compared to the TiO2 nano particles, the hierarchically meso-macroporous TiO2 network containing 0.18 wt % Pt/PtO phase-juneted cocatalyst demonstrates a highest photocatalytic H-2 rate of 13 mmol g(-1) h(-1) under simulated solar light, and possesses a stable cycling activity without obvious decrease after five cycles. Such high H-2 production performance can be attributed to both the phase-juncted Pt/PtO providing more active sites while PtO suppresses the undesirable hydrogen back reaction, and the special hierarchically porous TiO2 network with inner-particle mesopores presenting short diffusion path lengths for photogenerated electrons and enhanced light harvesting efficiency. This work suggests that Pt/PtO phase-juncted cocatalyst on hierarchically porous TiO2 nanostructures is a promising strategy for advanced photocatalytic H-2 production. |
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Place of Publication |
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Wos |
000410597500032 |
Publication Date |
2017-08-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
18 |
Open Access |
OpenAccess |
Notes |
; B.L.S. acknowledges the Chinese Central Government for an “Expert of the State” position in the Program of the “Thousand Talents”. Y.L. acknowledges the Hubei Provincial Department of Education for the “Chutian Scholar” program. This work is supported by the National Key Research and Development Program of China (2016YFA0202602), Program for Changjiang Scholars and Innovative Research Team in University (IRT_15R52), International Science & Technology Cooperation Program of China (2015DFE52870), National Natural Science Foundation of China (51502225), and the Fundamental Research Funds for the Central Universities (WUT: 2016III029). Z.Y.H. and G.V.T. acknowledge support from the EC Framework 7 program ESTEEM2 (Reference 312483). ; |
Approved |
Most recent IF: 7.504 |
Call Number |
UA @ lucian @ c:irua:146765 |
Serial |
4779 |
Permanent link to this record |
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Author |
Asapu, R.; Ciocarlan, R.-G.; Claes, N.; Blommaerts, N.; Minjauw, M.; Ahmad, T.; Dendooven, J.; Cool, P.; Bals, S.; Denys, S.; Detavernier, C.; Lenaerts, S.; Verbruggen, S.W. |
Title |
Plasmonic Near-Field Localization of Silver Core–Shell Nanoparticle Assemblies via Wet Chemistry Nanogap Engineering |
Type |
A1 Journal article |
Year |
2017 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
9 |
Issue |
9 |
Pages |
41577-41585 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Silver nanoparticles are widely used in the field of plasmonics because of their unique optical properties. The wavelength-dependent surface plasmon resonance gives rise to a strongly enhanced electromagnetic field, especially at so-called hot spots located in the nanogap in-between metal nanoparticle assemblies. Therefore, the interparticle distance is a decisive factor in plasmonic applications, such as surface-enhanced Raman spectroscopy (SERS). In this study, the aim is to engineer this interparticle distance for silver nanospheres using a convenient wet-chemical approach and to predict and quantify the corresponding enhancement factor using both theoretical and experimental tools. This was done by building a tunable ultrathin polymer shell around the nanoparticles using the layer-by-layer method, in which the polymer shell acts as the separating interparticle spacer layer. Comparison of different theoretical approaches and corroborating the results with SERS analytical experiments using silver and silver−polymer core−shell nanoparticle clusters as SERS substrates was also done. Herewith, an approach is provided to estimate the extent of plasmonic near-field enhancement both theoretically as well as experimentally. |
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Place of Publication |
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Wos |
000417005900057 |
Publication Date |
2017-11-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
29 |
Open Access |
OpenAccess |
Notes |
financial support through a research fellowship. C.D. wishes to thank the Hercules foundation for the financial support (SPINAL). P.C. and R.-G.C. acknowledge financial support by FWO Vlaanderen (project no. G038215N). N.C. and S.B. acknowledge the financial support from the European Research Council (ERC starting grant #335078-COLOURATOM). (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); saraecas; ECAS_Sara; |
Approved |
Most recent IF: 7.504 |
Call Number |
EMAT @ emat @c:irua:147243 |
Serial |
4804 |
Permanent link to this record |
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Author |
Wu, J.; Zhang, L.; Xin, X.; Zhang, Y.; Wang, H.; Sun, A.; Cheng, Y.; Chen, X.; Xu, G. |
Title |
Electrorheological fluids with high shear stress based on wrinkly tin titanyl oxalate |
Type |
A1 Journal article |
Year |
2018 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
10 |
Issue |
7 |
Pages |
6785-6792 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Electrorheological (ER) fluids are considered as a type of smart fluids because their rheological characteristics can be altered through an electric field. The discovery of giant ER effect revived the researchers' interest in the ER technological area. However, the poor stability including the insufficient dynamic shear stress, the large leakage current density, and the sedimentation tendency still hinders their practical applications. Herein, we report a facile and scalable coprecipitation method for synthesizing surfactant-free tin titanyl oxalate (TTO) particles with tremella-like wrinkly microstructure (W-TTO). The W-TTO-based ER fluids exhibit enhanced ER activity compared to that of the pristine TTO because of the improved wettability between W-TTO and the silicone oil. In addition, the static yield stress and leakage current of W-TTO ER fluids also show a fine time stability during the 30 day tests. More importantly, the dynamic shear stress of W-TTO ER fluids can remain stable throughout the shear rate range, which is valuable for their use in engineering applications. The results in this work provided a promising strategy to solving the long-standing problem of ER fluid stability. Moreover, this convenient route of synthesis may be considered a green approach for the mass production of giant ER materials. |
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Place of Publication |
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Wos |
000426143900081 |
Publication Date |
2018-02-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
7 |
Open Access |
OpenAccess |
Notes |
; The work was supported by the National Natural Science Foundation of China (Grant 21573267, 11674335), the Youth Innovation Promotion Association CAS (2013196), and the Program for Ningbo Municipal Science and Technology Innovative Research Team (2015B11002, 2016B10005). ; |
Approved |
Most recent IF: 7.504 |
Call Number |
UA @ lucian @ c:irua:149911 |
Serial |
4931 |
Permanent link to this record |
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Author |
Ben Dkhil, S.; Pfannmöller, M.; Schroeder, R.R.; Alkarsifi, R.; Gaceur, M.; Koentges, W.; Heidari, H.; Bals, S.; Margeat, O.; Ackermann, J.; Videlot-Ackermann, C. |
Title |
Interplay of interfacial layers and blend composition to reduce thermal degradation of polymer solar cells at high temperature |
Type |
A1 Journal article |
Year |
2018 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
10 |
Issue |
10 |
Pages |
3874-3884 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The thermal stability of printed polymer solar cells at elevated temperatures needs to be improved to achieve high-throughput fabrication including annealing steps as well as long-term stability. During device processing, thermal annealing impacts both the organic photoactive layer, and the two interfacial layers make detailed studies of degradation mechanism delicate. A recently identified thermally stable poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b'-dithiopherie-2,6-diyl] [3-fluoro-2-[(2-ethylhexyl) carbonyl] thieno [3,4-b]thiophenediyl]] : [6,6]-phenyl- C-71-butyric acid methyl ester (PTB7:PC70BM) blend as photoactive layer in combination with poly(3,4-ethylenedioxythiophene) polystyrene sulfonate as hole extraction layer is used here to focus on the impact of electron extraction layer (EEL) on the thermal stability of solar cells. Solar cells processed with densely packed ZnO nanoparticle layers still show 92% of the initial efficiency after constant annealing during 1 day at 140 degrees C, whereas partially covering ZnO layers as well as an evaporated calcium layer leads to performance losses of up to 30%. This demonstrates that the nature and morphology of EELs highly influence the thermal stability of the device. We extend our study to thermally unstable PTB7:[6,6]-phenyl-C-61-butyric acid methyl ester (PC60BM) blends to highlight the impact of ZnO on the device degradation during annealing. Importantly, only 12% loss in photocurrent density is observed after annealing at 140 degrees C during 1 day when using closely packed ZnO. This is in stark contrast to literature and addressed here to the use of a stable double-sided confinement during thermal annealing. The underlying mechanism of the inhibition of photocurrent losses is revealed by electron microscopy imaging and spatially resolved spectroscopy. We found that the double-sided confinement suppresses extensive fullerene diffusion during the annealing step, but with still an increase in size and distance of the enriched donor and acceptor domains inside the photoactive layer by an average factor of 5. The later result in combination with comparably small photocurrent density losses indicates the existence of an efficient transport of minority charge carriers inside the donor and acceptor enriched phases in PTB7:PC60BM blends. |
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Place of Publication |
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Wos |
000424728800082 |
Publication Date |
2018-01-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
9 |
Open Access |
OpenAccess |
Notes |
; We acknowledge the financial support by the French Fond Unique Interministeriel (FUI) under the project “SFUMATO” (grant number: F1110019V/201308815) as well as by the European Commission under the Project “SUNFLOWER” (FP7-ICT-2011-7-contract number: 287594). M.P. and R.R.S. acknowledge support by the HeiKA (Heidelberg Karlsruhe Research Partnership) FunTech-3D materials science program. ; |
Approved |
Most recent IF: 7.504 |
Call Number |
UA @ lucian @ c:irua:149309UA @ admin @ c:irua:149309 |
Serial |
4939 |
Permanent link to this record |
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Author |
Gasparotto, A.; Maccato, C.; Carraro, G.; Sada, C.; Štangar, U.L.; Alessi, B.; Rocks, C.; Mariotti, D.; La Porta, A.; Altantzis, T.; Barreca, D. |
Title |
Surface Functionalization of Grown-on-Tip ZnO Nanopyramids: From Fabrication to Light-Triggered Applications |
Type |
A1 Journal Article |
Year |
2019 |
Publication |
Acs Applied Materials & Interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
11 |
Issue |
17 |
Pages |
15881-15890 |
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
Abstract |
We report on a combined chemical vapor deposition (CVD)/radio frequency (RF) sputtering synthetic strategy for the controlled surface modification of ZnO nanostructures by Ti-containing species. Specifically, the proposed approach consists in the CVD of grown-on-tip ZnO nanopyramids, followed by titanium RF sputtering under mild conditions. The results obtained by a thorough characterization demonstrate the successful ZnO surface functionalization with dispersed Ti-containing species in low amounts. This phenomenon, in turn, yields a remarkable enhancement of photoactivated superhydrophilic behavior, self-cleaning ability, and photocatalytic performances in comparison to bare ZnO. The reasons accounting for such an improvement are unravelled by a multitechnique analysis, elucidating the interplay between material chemico-physical properties and the corresponding functional behavior. Overall, the proposed strategy stands as an amenable tool for the mastering of semiconductor-based functional nanoarchitectures through ad hoc engineering of the system surface. |
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Place of Publication |
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Language |
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Wos |
000466988800078 |
Publication Date |
2019-04-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
|
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
1 |
Open Access |
Not_Open_Access |
Notes |
The research leading to these results has received financial support from Padova University ACTION postdoc fellowship, DOR 2016-2018, P-DiSC #03BIRD2016-UNIPD projects, and HERALD COST Action MP1402-37831. The support from EPSRC (awards EP/R008841/1 and EP/M024938/1) as well as from the Slovenian Research Agency (research core funding No. P1-0134) is also recognized. T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO, Belgium). The authors are grateful to Dr. Sebastiano Pianta (Department of Chemical Sciences, Padova University, Italy) for experimental assistance. |
Approved |
Most recent IF: 7.504 |
Call Number |
EMAT @ emat @ |
Serial |
5185 |
Permanent link to this record |
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Author |
Retuerto, M.; Calle-Vallejo, F.; Pascual, L.; Lumbeeck, G.; Fernandez-Diaz, M.T.; Croft, M.; Gopalakrishnan, J.; Pena, M.A.; Hadermann, J.; Greenblatt, M.; Rojas, S. |
Title |
La1.5Sr0.5NiMn0.5Ru0.5O6 double perovskite with enhanced ORR/OER bifunctional catalytic activity |
Type |
A1 Journal article |
Year |
2019 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
11 |
Issue |
24 |
Pages |
21454-21464 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Perovskites (ABO(3)) with transition metals in active B sites are considered alternative catalysts for the water oxidation to oxygen through the oxygen evolution reaction (OER) and for the oxygen reduction through the oxygen reduction reaction (ORR) back to water. We have synthesized a double perovskite (A(2)BB'O-6) with different cations in A, B, and B' sites, namely, ((La15Sr0.5)-Sr-.)(A)(Ni0.5Mn0.5)(B)(Ni0.5Ru0.5)(B)O-6 (LSNMR), which displays an outstanding OER/ORR bifunctional performance. The composition and structure of the oxide has been determined by powder X-ray diffraction, powder neutron diffraction, and transmission electron microscopy to be monoclinic with the space group P2(1)/n and with cationic ordering between the ions in the B and B' sites. X-ray absorption near-edge spectroscopy suggests that LSNMR presents a configuration of similar to Ni2+, similar to Mn4+, and similar to Ru5+. This bifunctional catalyst is endowed with high ORR and OER activities in alkaline media, with a remarkable bifunctional index value of similar to 0.83 V (the difference between the potentials measured at -1 mA cm(-2) for the ORR and +10 mA cm(-2) for the OER). The ORR onset potential (E-onset) of 0.94 V is among the best reported to date in alkaline media for ORR-active perovskites. The ORR mass activity of LSNMR is 1.1 A g(-1) at 0.9 V and 7.3 A g(-1) at 0.8 V. Furthermore, LSNMR is stable in a wide potential window down to 0.05 V. The OER potential to achieve a current density of 10 mA cm(-2) is 1.66 V. Density functional theory calculations demonstrate that the high ORR/OER activity of LSNMR is related to the presence of active Mn sites for the ORR- and Ru-active sites for the OER by virtue of the high symmetry of the respective reaction steps on those sites. In addition, the material is stable to ORR cycling and also considerably stable to OER cycling. |
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Wos |
000472683300019 |
Publication Date |
2019-05-30 |
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ISSN |
1944-8244 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
12 |
Open Access |
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Notes |
; This work was supported by the ENE2016-77055-C3-3-R project from the Spanish Ministry of Economy and Competitiveness (MINECO) and PIE 201480E122 from CSIC. M.R. thanks MINECO's Juan de la Cierva program for a grant (FPDI-2013-17582). F.C.-V. thanks the Spanish MEC for a Ramon y Cajal research contract (RYC-2015-18996). M.G. acknowledges the support from NSF-DMR-1507252 grant, NJ, USA. ; |
Approved |
Most recent IF: 7.504 |
Call Number |
UA @ admin @ c:irua:161320 |
Serial |
5400 |
Permanent link to this record |
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Author |
Peng, X.; Peng, H.; Zhao, K.; Zhang, Y.; Xia, F.; Lyu, J.; Van Tendeloo, G.; Sun, C.; Wu, J. |
Title |
Direct visualization of atomic-scale heterogeneous structure dynamics in MnO₂ nanowires |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Acs Applied Materials & Interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
13 |
Issue |
28 |
Pages |
33644-33651 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Manganese oxides are attracting great interest owing to their rich polymorphism and multiple valent states, which give rise to a wide range of applications in catalysis, capacitors, ion batteries, and so forth. Most of their functionalities are connected to transitions among the various polymorphisms and Mn valences. However, their atomic-scale dynamics is still a great challenge. Herein, we discovered a strong heterogeneity in the crystalline structure and defects, as well as in the Mn valence state. The transitions are studied by in situ transmission electron microscopy (TEM), and they involve a complex ordering of [MnO6] octahedra as the basic building tunnels. MnO2 nanowires synthesized using solution-based hydrothermal methods usually exhibit a large number of multiple polymorphism impurities with different tunnel sizes. Upon heating, MnO2 nanowires undergo a series of stoichiometric polymorphism changes, followed by oxygen release toward an oxygen-deficient spinel and rock-salt phase. The impurity polymorphism exhibits an abnormally high stability with interesting small-large-small tunnel size transition, which is attributed to a preferential stabilizer (K+) concentration, as well as a strong competition of kinetics and thermodynamics. Our results unveil the complicated intergrowth of polymorphism impurities in MnO2, which provide insights into the heterogeneous kinetics, thermodynamics, and transport properties of the tunnel-based building blocks. |
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Wos |
000677540900101 |
Publication Date |
2021-07-08 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor ![sorted by Impact Factor field, ascending order (up)](img/sort_asc.gif) |
7.504 |
Times cited |
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Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: 7.504 |
Call Number |
UA @ admin @ c:irua:180450 |
Serial |
6861 |
Permanent link to this record |