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“Some critical observations about the degradation of glass : the formation of lamellae explained”. Schalm O, Nuyts G, Janssens K, Journal Of Non-Crystalline Solids 569, 120984 (2021). http://doi.org/10.1016/J.JNONCRYSOL.2021.120984
Abstract: This study demonstrates that the mechanism responsible for the transformation of glass into a degradation layer is pH-dependent. In acid conditions, the transformed glass is homogeneous and brittle. In mild alkaline conditions, transformed glass is heterogeneous due to the presence of lamellae composed of silica nanoparticles and the occurrence of Ca-rich inclusions. The fundamental difference between acid and alkaline conditions cannot be explained by the currently accepted degradation mechanism based on ion exchange. To explain this critical observation, we propose a refined degradation mechanism based on existing knowledge that involves several inwardly moving reaction fronts. The fronts responsible for the transformation of the silicate network into amorphous silica are also responsible for the morphology of the transformed glass. We have identified the feedback mechanism that explains the formation of lamellae in alkaline conditions.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 2.124
DOI: 10.1016/J.JNONCRYSOL.2021.120984
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“Solvothermal synthesis of mesoporous TiO2 with tunable surface area, crystal size and surface hydroxylation for efficient photocatalytic acetaldehyde degradation”. Zhang K, Wang J, Ninakanti R, Verbruggen SW, Chemical engineering journal 474, 145188 (2023). http://doi.org/10.1016/J.CEJ.2023.145188
Abstract: Photocatalytic acetaldehyde degradation exhibits satisfactory performance only at relatively low acetaldehyde flow rates, predominately below 10 × 10-3 mL/min, leaving ample room for improvement. Therefore, it is necessary to prepare more efficient photocatalysts for acetaldehyde degradation. Moreover, the impact of the interaction strength between the titania surface and surface water on the photocatalytic acetaldehyde efficiency is poorly understood. To address these issues, in this work a series of (0 0 1)-faceted anatase titania samples with various surface properties and structures were synthesized via a solvothermal method and tested at high acetaldehyde flow rates under UV light irradiation. With increasing solvothermal time, the pore volume, surface area, and the abundance of surface OH groups all increased, while the crystallite size decreased. These were all identified to be beneficial to promote the degradation performance. When the solvothermal temperature was 180 ℃ and the reaction time was 5 h, the prepared sample displayed the most efficient performance at 19.25× 10-3 mL/min of acetaldehyde (conversion of (74 ± 1)% versus (29 ± 1)% for P25), and achieved a 100 % conversion at 16 × 10-3 mL/min. A weaker interaction strength between surface water and the titania surface was found to improve the acetaldehyde adsorption capacity, thereby promoting the acetaldehyde degradation efficiency. The stability of the best performing sample was tested over 48 h, demonstrating a highly stable performance with no signs of deactivation. Even at a relative humidity of 30 %, the acetaldehyde conversion retains 82% of its efficiency in a dry atmosphere, highlighting its potential in practical applications.
Keywords: A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA)
Impact Factor: 15.1
DOI: 10.1016/J.CEJ.2023.145188
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“Solving the structure of Li ion battery materials with precession electron diffraction : application to Li2CoPo4F”. Hadermann J, Abakumov AM, Turner S, Hafideddine Z, Khasanova NR, Antipov EV, Van Tendeloo G, Chemistry of materials 23, 3540 (2011). http://doi.org/10.1021/cm201257b
Abstract: The crystal structure of the Li2CoPO4F high-voltage cathode for Li ion rechargeable batteries has been completely solved from precession electron diffraction (PED) data, including the location of the Li atoms. The crystal structure consists of infinite chains of CoO4F2 octahedra sharing common edges and linked into a 3D framework by PO4 tetrahedra. The chains and phosphate anions together delimit tunnels filled with the Li atoms. This investigation demonstrates that PED can be successfully applied for obtaining structural information on a variety of Li-containing electrode materials even from single micrometer-sized crystallites.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 46
DOI: 10.1021/cm201257b
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“Solving mercury (Hg) speciation in soil samples by synchrotron X-ray microspectroscopic techniques”. Terzano R, Santoro A, Spagnuolo M, Vekemans B, Medici L, Janssens K, Göttlicher J, Denecke MA, Mangold S, Ruggiero P, Environmental pollution 158, 2702 (2010). http://doi.org/10.1016/J.ENVPOL.2010.04.016
Abstract: Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg1. Hg chemical forms were identified and quantified by sequential extractions and bulkand micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as m-XRF, m-XRD and m-XANES were necessary to solve bulk Hg speciation, in both soil fractions <2 mm and <2 mm. The main Hg-species found in the soil samples were metacinnabar (b-HgS), cinnabar (a-HgS), corderoite (Hg3S2Cl2), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 mm. No interaction among Hg-species and soil components was observed. All the observed Hgspecies originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 5.099
Times cited: 30
DOI: 10.1016/J.ENVPOL.2010.04.016
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“Solving hindered groundwater dynamics in restored tidal marshes by creek excavation and soil amendments : a model study”. Van Putte N, Meire P, Seuntjens P, Joris I, Verreydt G, Hambsch L, Temmerman S, Ecological engineering: the journal of ecotechnology 178, 106583 (2022). http://doi.org/10.1016/J.ECOLENG.2022.106583
Abstract: Groundwater fluxes in tidal marshes largely control key ecosystem functions and services, such as vegetation growth, soil carbon sequestration, and nutrient cycling. In tidal marshes restored on formerly embanked agricultural land, groundwater fluxes are often limited as compared to nearby natural marshes, as a result of historical agricultural soil compaction. To improve the functioning of restored tidal marshes, knowledge is needed on how much certain design options can optimize soil-groundwater interactions in future restoration projects. Based on measured data on soil properties and tidally induced groundwater dynamics, we calibrated and evaluated a 2D vertical model of a creek-marsh cross-section, accounting for both saturated and unsaturated groundwater flow and solute transport in a variably saturated groundwater flow model. We found that model simulations of common restoration practices such as soil amendments (increasing the depth of porous soil on top of the compact layer) and creek excavation (increasing the creek density) increase the soil aeration depth and time, the drainage depth and the solute flux, and decrease the residence time of solutes in the porewater. Our simulations indicate that increasing the depth to the compact layer from 20 cm to 40 cm, or increasing the creek density from 1 creek to 2 creeks along a 50 m marsh transect (while maintaining the total creek cross-sectional area), in both cases more than doubles the volume of water processed by the marsh soil. We discuss that this may stimulate nutrient cycling. As such, our study demonstrates that groundwater modelling can support the design of marsh restoration measures aiming to optimize groundwater fluxes and related ecosystem services.
Keywords: A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL); Ecosphere
Impact Factor: 3.8
DOI: 10.1016/J.ECOLENG.2022.106583
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“Solution-processable ultrathin size- and shape-controlled colloidal Cu2-xS nanosheets”. van der Stam W, Akkerman QA, Ke X, van Huis MA, Bals S, de Donega CM, Chemistry of materials 27, 283 (2015). http://doi.org/10.1021/cm503929q
Abstract: Ultrathin two-dimensional (2D) nanosheets (NSs) possess extraordinary properties that are attractive for both fundamental studies and technological devices. Solution-based bottom-up methods are emerging as promising routes to produce free-standing NSs, but the synthesis of colloidal NSs with well-defined size and shape has remained a major challenge. In this work, we report a novel method that yields 2 nm thick colloidal Cu2-xS NSs with well-defined shape (triangular or hexagonal) and size (100 nm to 3 mu m). The key feature of our approach is the use of a synergistic interaction between halides (Br or Cl) and copper-thiolate metal-organic frameworks to create a template that imposes 2D constraints on the Cu-catalyzed C-S thermolysis, resulting in nucleation and growth of colloidal 2D Cu2-xS NSs. Moreover, the NS composition can be postsynthetically tailored by exploiting topotactic cation exchange reactions. This is illustrated by converting the Cu2-xS NSs into ZnS and CdS NSs while preserving their size and shape. The method presented here thus holds great promise as a route to solution-processable compositionally diverse ultrathin colloidal NSs with well-defined shape and size.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 68
DOI: 10.1021/cm503929q
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“Solution-gel-based surface modification of LiNi0.5Mn1.5O4-δ with amorphous Li-Ti-O coating”. Ulu Okudur F, Batuk M, Hadermann J, Safari M, De Sloovere D, Kumar Mylavarapu S, Joos B, D'Haen J, Van Bael MK, Hardy A, RSC advances 13, 33146 (2023). http://doi.org/10.1039/D3RA05599J
Abstract: LNMO (LiNi0.5Mn1.5O4-delta) is a high-energy density positive electrode material for lithium ion batteries. Unfortunately, it suffers from capacity loss and impedance rise during cycling due to electrolyte oxidation and electrode/electrolyte interface instabilities at high operating voltages. Here, a solution-gel synthesis route was used to coat 0.5-2.5 mu m LNMO particles with amorphous Li-Ti-O (LTO) for improved Li conduction, surface structural stability and cyclability. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) analysis coupled with energy dispersive X-ray (EDX) showed Ti-rich amorphous coatings/islands or Ti-rich spinel layers on many of the LTO-modified LNMO facets, with a thickness varying from about 1 to 10 nm. The surface modification in the form of amorphous islands was mostly possible on high-energy crystal facets. Physicochemical observations were used to propose a molecular mechanism for the surface modification, combining insights from metalorganic chemistry with the crystallographic properties of LNMO. The improvements in functional properties were investigated in half cells. The cell impedance increased faster for the bare LNMO compared to amorphous LTO modified LNMO, resulting in R-ct values as high as 1247 Omega (after 1000 cycles) for bare LNMO, against 216 Omega for the modified material. At 10C, the modified material boosted a 15% increase in average discharge capacity. The improvements in electrochemical performance were attributed to the increase in electrochemically active surface area, as well as to improved HF-scavenging, resulting in the formation of protective byproducts, generating a more stable interface during prolonged cycling.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.9
DOI: 10.1039/D3RA05599J
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“Solution-derived YBa2Cu3O7-\delta (YBCO) superconducting films with BaZrO3 (BZO) nanodots based on reverse micelle stabilized nanoparticles”. Bretos I, Schneller T, Falter M, Baecker M, Hollmann E, Woerdenweber R, Molina-Luna L, Van Tendeloo G, Eibl O, Journal of materials chemistry C : materials for optical and electronic devices 3, 3971 (2015). http://doi.org/10.1039/c4tc02543a
Abstract: Superconducting YBa2Cu3O7-delta (YBCO) films with artificial BaZrO3 (BZO) nanodots were prepared using a chemical solution deposition method involving hybrid solutions composed of trifluoroacetate-based YBCO precursors and reverse micelle stabilized BZO nanoparticle dispersions. Microemulsion-mediated synthesis was used to obtain nano-sized (similar to 12 nm) and mono-dispersed BZO nanoparticles that preserve their features once introduced into the YBCO solution, as revealed by dynamic light scattering. Phase pure, epitaxial YBCO films with randomly oriented BZO nanodots distributed over their whole microstructure were grown from the hybrid solutions on (100) LaAlO3 substrates. The morphology of the YBCO-BZO nanocomposite films was strongly influenced by the amount of nanoparticles incorporated into the system, with contents ranging from 5 to 40 mol%. Scanning electron microscopy showed a high density of isolated second-phase defects consisting of BZO nanodots in the nanocomposite film with 10 mol% of BZO. Furthermore, a direct observation and quantitative analysis of lattice defects in the form of interfacial edge dislocations directly induced by the BZO nanodots was evidenced by transmission electron microscopy. The superconducting properties (77 K) of the YBCO films improved considerably by the presence of such nanodots, which seem to enhance the morphology of the sample and therefore the intergranular critical properties. The incorporation of preformed second-phase defects (here, BZO) during the growth of the superconducting phase is the main innovation of this novel approach for the all-solution based low-cost fabrication of long-length coated conductors.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 5.256
Times cited: 19
DOI: 10.1039/c4tc02543a
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“Solubilization of struvite as a sustainable nutrient source for single cell protein production”. Muys M, Derese S, Verliefde A, Vlaeminck SE, Communications in agricultural and applied biological sciences 81, 179 (2016)
Abstract: By 2050, the world population will have considerably expanded and the life standard of many will increase, yielding a 50% higher demand in protein (FAO, 2011), and even increases of 82 and 102% for diary and meat products, respectively (Boland et al., 2013). To provide in this increasing demand we are highly dependent on our classical fertilizer to food chain which has a high environmental impact and lacks efficiency. Nutrient losses cause eutrophication and biodiversity loss and the input of resources is already beyond the boundaries of environmental sustainability (Steffen et al., 2015). Phosphate fertilizers are made from phosphate rock (apatite), of which the reserves are predicted to be depleted within 50 100 years if we continue business as usual (Cordell et al., 2009). Next to problems related to the unbalanced geopolitical distribution with dominance in China and Morocco, the decreasing quality of the remaining apatite will result in an increasing environmental impact of fertilizer production. Finally, our traditional food production model requires 30% of all ice-free land, 70% of all available freshwater and produces up to one third of the global greenhouse gas emission, of which 80 to 86% is linked to agricultural production (Vermeulen et al., 2012). To ensure food security, nutrient recovery from waste streams can provide an important strategy. In this context, struvite ( ) crystallisation may be applied to recover phosphorus, along with some nitrogen. Reusing these nutrients as agricultural fertilizer on the field will lead to considerable losses to the environment. In contrast, their use to cultivate micro-organisms, e.g. for single cell protein (SCP), offers to potential of a near perfect conversion efficiency (Moed et al., 2015). At this moment, microalgae represent the most developed type of SCP, and are a promising protein source due to their growth rate, high nutritional quality and extremely high nutrient usage efficiency (Becker, 2007). Reliable solubilisation data are essential to design a technological strategy for struvite dosage in bioreactors for SCP production. The effect on solubility and solubilisation rate of relevant physicochemical parameters was studied experimentally in aqueous solutions. Because pH and temperature greatly affect solubilisation kinetics they were set at a constant value of 7 and 20°C respectively. The effect of some parameters on struvite solubility was already studied (Bhuiyan et al., 2007; Ariyanto et al., 2014; Roncal-Herrero and Oelkers, 2011), but solubilisation rates were not yet considered and pH was not controlled at a constant value. The chemical parameters considered in this study include the concentration of different common ions ( and ), foreign ions ( and the chelating agent ethylenediaminetetraacetic acid, EDTA) present in micro-algal cultivation media as well as ionic strength (as set by NaCl). The main physical parameter included was contact surface, through variation in initial particle size and as well as in struvite dosage concentration.
Keywords: A2 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
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“Soliton motion induced along ferromagnetic skyrmion chains in chiral thin nanotracks”. Souza JCB, Vizarim NP, Reichhardt CJO, Reichhardt C, Venegas PA, Journal of magnetism and magnetic materials 587, 171280 (2023). http://doi.org/10.1016/J.JMMM.2023.171280
Abstract: Using atomistic magnetic simulations we investigate the soliton motion along a pinned skyrmion chain containing an interstitial skyrmion. We find that the soliton can exhibit stable motion along the chain without a skyrmion Hall effect for an extended range of drives. Under a constant drive the solitons have a constant velocity. We also measure the skyrmion velocity-current curves and identify the signatures of different phases including a pinned phase, stable soliton motion, and quasi-free motion at higher drives where all of the skyrmions depin from the pinning centers and move along the rigid wall. In the quasi-free motion regime, the velocity is oscillatory due to the motion of the skyrmions over the pinning sites. For increasing pinning strength, the onset of soliton motion shifts to higher values of current density. We also find that for stronger pinning, the characteristic velocity-current shape is affected by the annihilation of single or multiple skyrmions in the drive interval over which the soliton motion occurs. Our results indicate that stable skyrmion soliton motion is possible and that the solitons could be used as information carriers instead of the skyrmions themselves for technological applications.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.7
DOI: 10.1016/J.JMMM.2023.171280
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“Soliton motion in skyrmion chains : stabilization and guidance by nanoengineered pinning”. Vizarim NP, Souza JCB, Reichhardt CJO, Reichhardt C, Milošević, MV, Venegas PA, Physical review B 105, 224409 (2022). http://doi.org/10.1103/PHYSREVB.105.224409
Abstract: Using a particle-based model we examine the depinning motion of solitons in skyrmion chains in quasi -onedimensional (1D) and two-dimensional (2D) systems containing embedded 1D interfaces. The solitons take the form of a particle or hole in a commensurate chain of skyrmions. Under an applied drive, just above a critical depinning threshold, the soliton moves with a skyrmion Hall angle of zero. For higher drives, the entire chain depins, and in a 2D system we observe that both the solitons and chain move at zero skyrmion Hall angle and then transition to a finite skyrmion Hall angle as the drive increases. In a 2D system with a 1D interface that is at an angle to the driving direction, there can be a reversal of the sign of the skyrmion Hall angle from positive to negative. Our results suggest that solitons in skyrmion systems could be used as information carriers in racetrack geometries that would avoid the drawbacks of finite skyrmion Hall angles. The soliton states become mobile at significantly lower drives than the depinning transition of the skyrmion chains themselves.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.7
Times cited: 2
DOI: 10.1103/PHYSREVB.105.224409
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“Solidelectrolyte interphase evolution of carbon-coated silicon nanoparticles for lithium-ion batteries monitored by transmission electron microscopy and impedance spectroscopy”. Van Havenbergh K, Turner S, Driesen K, Bridel J-S, Van Tendeloo G, Energy technology 3, 699 (2015). http://doi.org/10.1002/ente.201500034
Abstract: The main drawbacks of silicon as the most promising anode material for lithium-ion batteries (theoretical capacity=3572 mAh g−1) are lithiation-induced volume changes and the continuous formation of a solidelectrolyte interphase (SEI) upon cycling. A recent strategy is to focus on the influence of coatings and composite materials. To this end, the evolution of the SEI, as well as an applied carbon coating, on nanosilicon electrodes during the first electrochemical cycles is monitored. Two specific techniques are combined: Transmission Electron Microscopy (TEM) is used to study the surface evolution of the nanoparticles on a very local scale, whereas electrochemical impedance spectroscopy (EIS) provides information on the electrode level. A TEMEELS fingerprint signal of carbonate structures from the SEI is discovered, which can be used to differentiate between the SEI and a graphitic carbon matrix. Furthermore, the shielding effect of the carbon coating and the thickness evolution of the SEI are described.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 2.789
DOI: 10.1002/ente.201500034
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“Solid state speciation and potential bioavailability of depleted uranium particles from Kosovo and Kuwait”. Lind OC, Salbu B, Skipperud L, Janssens K, Jaroszewicz J, de Nolf W, Journal of environmental radioactivity 100, 301 (2009). http://doi.org/10.1016/J.JENVRAD.2008.12.018
Abstract: A combination of synchrotron radiation based X-ray microscopic techniques (ì-XRF, ì-XANES, ì-XRD) applied on single depleted uranium (DU) particles and semi-bulk leaching experiments has been employed to link the potential bioavailability of DU particles to site-specific particle characteristics. The oxidation states and crystallographic forms of U in DU particles have been determined for individual particles isolated from selected samples collected at different sites in Kosovo and Kuwait that were contaminated by DU ammunition during the 1999 Balkan conflict and the 1991 Gulf war. Furthermore, small soil or sand samples heavily contaminated with DU particles were subjected to simulated gastrointestinal fluid (0.16 M HCl) extractions. Characteristics of DU particles in Kosovo soils collected in 2000 and in Kuwait soils collected in 2002 varied significantly depending on the release scenario and to some extent on weathering conditions. Oxidized U (+6) was determined in large, fragile and bright yellow DU particles released during fire at a DU ammunition storage facility and crystalline phases such as schoepite (UO3·2.25H2O), dehydrated schoepite (UO3·0.75H2O) and metaschoepite (UO3·2.0H2O) were identified. As expected, these DU particles were rapidly dissolved in 0.16 M HCl (84 ± 3% extracted after 2 h) indicating a high degree of potential mobility and bioavailability. In contrast, the 2 h extraction of samples contaminated with DU particles originating either from corrosion of unspent DU penetrators or from impacted DU ammunition appeared to be much slower (2030%) as uranium was less oxidized (+4 to +6). Crystalline phases such as UO2, UC and metallic U or UTi alloy were determined in impacted DU particles from Kosovo and Kuwait, while the UO2,34 phase, only determined in particles from Kosovo, could reflect a more corrosive environment. Although the results are based on a limited number of DU particles, they indicate that the structure and extractability of DU particles released from similar sources (metallic U penetrators) will depend on the release scenarios (fire, impact) and to some extent environmental conditions. However, most of the DU particles (7396%) in all investigated samples were dissolved in 0.16 M HCl after one week indicating that a majority of the DU material is bioaccessible.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 2.31
Times cited: 49
DOI: 10.1016/J.JENVRAD.2008.12.018
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Dingenen F (2023) Solar-driven H2 production from seawater using stabilized plasmon-enhanced photocatalysts. XXXVIII, 210 p
Abstract: As natural gas prices proved to be very volatile, sustainable alternatives are highly needed. Water-derived H2 was revealed as a promising substitute, allowing to produce a green energy carrier with a minimum of harmful emissions. Direct splitting of earth-abundant seawater provides an eco-friendly route for the production of clean H2, but is hampered by selectivity and stability issues due to the presence of salts.Photocatalytic seawater splitting is particularly promising for this purpose, as it seems less affected by adversary seawater effects and might rely on free and renewable solar power. Unfortunately, the benchmark photocatalyst, TiO2, still suffers from its low solar light activity. It is only actived upon illumination with energetic ultraviolet light (<5% of the sunlight). In order to broaden the activity window to the visible light, the concept of the 'plasmonic rainbow' was explored. Here, TiO2 is modified with various gold-silver composites that possess the unique optical phenomenon of Surface Plasmon Resonance (SPR). This phenomenon enables the absorption of light at very specific wavelengths, depending on the metal type, size, shape and dielectric environment. The light energy might then be converted into hot carriers, strong local electromagnetic fields and/or heat. By combining multiple composites with various sizes and compositions, a broadband absorption could be obtained, resulting in significantly enhanced activity in photocatalytic model reactions under simulated sunlight. The major disadvantage of these plasmonic nanoparticles is their tendency to oxidize and deactivate. To overcome this, polymer shell stabilization strategies were found to be effective to protect the metal cores. Both conductive and non-conductive polymers were studied. For the former, a mix-and-wait strategy generating polyaniline shells of 2-5 nm was used, whille the latter was based on a Layer-by-Layer approach, allowing (sub) nanometer thickness control. For the actual H2 production experiments, the plasmonic loading was optimized in a pure water:methanol scavenger (7:1) mixture and initially the stabilization strategies proofed to be effective for simulated seawater (0.5M NaCl), even after 2 years. However, in real seawater, the activity decreased drastically due to aggregation of the photocatalyst in the presence of multivalent cations. Finally, facile immobilization strategies using 3D printing showed to be able to yield stable, solar active photocatalyst for real seawater splitting.
Keywords: Doctoral thesis; Engineering sciences. Technology
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“Solar cooking in Senegalese villages : an application of best-worst scaling”. Vanschoenwinkel J, Lizin S, Swinnen G, Azadi H, Van Passel S, Energy Policy 67, 447 (2014). http://doi.org/10.1016/J.ENPOL.2013.12.038
Abstract: Dissemination programs of nontraditional cookstoves often fail. Nontraditional cookstoves aim to solve problems associated with biomass fuel usage in developing countries. Recent studies do not explain what drives user's cookstove choice. This study therefore builds a holistic framework that centralizes product-specific preferences or needs. The case study identifies product-specific factors that influence rural Senegalese inhabitants to switch to solar cooking, using best worst scaling. Looking at the preferences, the case study classified 126 respondents, in three distinct market segments with different solar cooking expectations. The paper identifies socio-demographic characteristics that explain these differences in the respondents' preferences. Finally, the respondent sample is divided in two groups: solar cooker owners and non-owners. When studied with regard to the same issue, solar cooker owners appear to value benefits of the solar cooker lower than non-owners. This is due to program factors (such as formations, after-sales network) and miscommunication (such as a wrong image of the solar cooker) that highly influenced the respondents' cookstove choice. As a conclusion, solar cookers and solar cooking programs are not always adapted to the needs and requirements of the end-users. Needs-oriented and end-user adopted strategies are necessary in order to successfully implement nontraditional cookstoves programs. (C) 2013 Elsevier Ltd. All rights reserved.
Keywords: A1 Journal article; Sociology; Engineering sciences. Technology; Engineering Management (ENM)
Impact Factor: 4.14
Times cited: 10
DOI: 10.1016/J.ENPOL.2013.12.038
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Peeters H (2023) Solar active photocatalytic self-cleaning coatings based on plasmon-embedded titania. XX, 125 p
Keywords: Doctoral thesis; Engineering sciences. Technology
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“Sol-gel hot injection synthesis of ZnO nanoparticles into a porous silica matrix and reaction mechanism”. Barhoum A, Van Assche G, Rahier H, Fleisch M, Bals S, Delplancked M-P, Leroux F, Bahnemann D, Materials &, design 119, 270 (2017). http://doi.org/10.1016/J.MATDES.2017.01.059
Abstract: Despite the enormous interest in the properties and applications of porous silica matrix, only a few attempts have been reported to deposit metal and metal oxide nanoparticles (NPs) inside the porous silica matrix. We report a simple approach (i.e. sol-gel hot injection) for insitu synthesis of ZnO NPs inside a porous silica matrix. Control of the Zn:Si molar ratio, reaction temperature, pH value, and annealing temperature permits formation of ZnO NPs (<= 10 nm) inside a porous silica particles, without additives or organic solvents. Results revealed that a solid state reaction inside the ZnO/SiO2 nanocomposites occurs with increasing the annealing temperature. The reaction of ZnO NPs with SiO2 matrix was insignificant up to approximately 500 degrees C. However, ZnO NPs react strongly with the silica matrix when the nanocomposites are annealed at temperatures above 700 degrees C. Extensive annealing of the ZnO/SiO2 nanocomposite at 900 degrees C yields 3D structures made of 500 nm rod-like, 5-7 pm tube-like and 35 pm needle-like Zn2SiO4 crystals. A possible mechanism for forming ZnO NPs inside porous silica matrix and phase transformation of the ZnO/SiO2 nanocomposites into 3D architectures of Zn2SiO4 are carefully discussed. (C) 2017 Elsevier Ltd. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.364
Times cited: 43
DOI: 10.1016/J.MATDES.2017.01.059
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“Soil warming increases the number of growing bacterial taxa but not their growth rates”. Metze D, Schnecker J, Le Noir de Carlan C, Bhattarai B, Verbruggen E, Ostonen I, Janssens IA, Sigurdsson BD, Hausmann B, Kaiser C, Richter A, Science Advances 10, eadk6295 (2024). http://doi.org/10.1126/SCIADV.ADK6295
Abstract: Soil microorganisms control the fate of soil organic carbon. Warming may accelerate their activities putting large carbon stocks at risk of decomposition. Existing knowledge about microbial responses to warming is based on community-level measurements, leaving the underlying mechanisms unexplored and hindering predictions. In a long-term soil warming experiment in a Subarctic grassland, we investigated how active populations of bacteria and archaea responded to elevated soil temperatures (+6°C) and the influence of plant roots, by measuring taxon-specific growth rates using quantitative stable isotope probing and 18 O water vapor equilibration. Contrary to prior assumptions, increased community growth was associated with a greater number of active bacterial taxa rather than generally faster-growing populations. We also found that root presence enhanced bacterial growth at ambient temperatures but not at elevated temperatures, indicating a shift in plant-microbe interactions. Our results, thus, reveal a mechanism of how soil bacteria respond to warming that cannot be inferred from community-level measurements.
Keywords: A1 Journal article; Plant and Ecosystems (PLECO) – Ecology in a time of change
Impact Factor: 13.6
DOI: 10.1126/SCIADV.ADK6295
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“Soil analysis by thin-film energy-dispersive X-ray fluorescence”. Van Grieken R, Van 't dack L, Costa Dantas C, Da Silveira Dantas H, Analytica chimica acta 108, 93 (1979). http://doi.org/10.1016/S0003-2670(01)93044-2
Abstract: Energy-dispersive x-ray fluorescence is advantageous for trace analysis of soils present as thin films. A target thickness of about 2 mg cm-2 provides a compromise between optimal sensitivity and minimal absorption effect or optimal accuracy. Sample preparation involves only suspending the finely ground soil in water and drying this suspension on a thin mylar foil glued on a ring that fits into the x.r.f. spectrometer. The effective sample weight present in the exciting beam area is computed from the scatter peaks, a method that cancels out target heterogeneity problems. High accuracy is demonstrated for many elements in reference soil and rock materials; a precision around 5% and a detection limit around 10 ppm can be achieved. As an illustration, results for 16 trace elements and preliminary interpretation are given for a series of pedologically important soil samples from Brasil.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/S0003-2670(01)93044-2
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“Soft vortex matter in a type-I/type-II superconducting bilayer”. Komendová, L, Milošević, MV, Peeters FM, Physical review : B : condensed matter and materials physics 88, 094515 (2013). http://doi.org/10.1103/PhysRevB.88.094515
Abstract: Magnetic flux patterns are known to strongly differ in the intermediate state of type-I and type-II superconductors. Using a type-I/type-II bilayer we demonstrate hybridization of these flux phases into a plethora of unique new ones. Owing to a complicated multibody interaction between individual fluxoids, many different intriguing patterns are possible under applied magnetic field, such as few-vortex clusters, vortex chains, mazes, or labyrinthal structures resembling the phenomena readily encountered in soft-matter physics. However, in our system the patterns are tunable by sample parameters, magnetic field, current, and temperature, which reveals transitions from short-range clustering to long-range ordered phases such as parallel chains, gels, glasses, and crystalline vortex lattices, or phases where lamellar type-I flux domains in one layer serve as a bedding potential for type-II vortices in the other, configurations clearly beyond the soft-matter analogy.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 27
DOI: 10.1103/PhysRevB.88.094515
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“Soft chemical control of the crystal and magnetic structure of a layered mixed valent manganite oxide sulfide”. Blandy JN, Abakumov AM, Christensen KE, Hadermann J, Adamson P, Cassidy SJ, Ramos S, Free DG, Cohen H, Woodruff DN, Thompson AL, Clarke SJ;, APL materials 3, 041520 (2015). http://doi.org/10.1063/1.4918973
Abstract: Oxidative deintercalation of copper ions from the sulfide layers of the layered mixed-valent manganite oxide sulfide Sr2MnO2Cu1.5S2 results in control of the copper-vacancy modulated superstructure and the ordered arrangement of magnetic moments carried by the manganese ions. This soft chemistry enables control of the structures and properties of these complex materials which complement mixed-valent perovskite and perovskite-related transition metal oxides. (C) 2015 Author(s).
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 4.335
Times cited: 5
DOI: 10.1063/1.4918973
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Admasu WF (2021) Socioeconomic and environmental impact of expropriation of agricultural land for urbanisation in Ethiopia. 162 p
Abstract: Globally, incorporation of agricultural lands into the urban boundary has been a common phenomenon. Governments use various alternatives to access the required land, including land expropriation procedures, which refers to the compulsorily taking of land from the landholders without their consent by paying compensation. In Ethiopia, the urban population is growing rapidly which resulted into an increase in the demand for urban land for housing construction, public services provision, and infrastructure developments. As the Ethiopian constitution prohibits sale of landholders, governments, at various levels, have been expropriating land from the surrounding farmers to meet the demand for urban land. The general objective of this thesis is to improve the understanding of the impacts of local land deals for urbanization on socioeconomics of farmers and the environment. The findings of this thesis revealed that there are gaps in the current practices of land expropriation for urban expansion that should be improved. The results showed that the compensation paid to the affected farmers is found to be economically inappropriate, i.e., not enough to restore the affected farmers’ livelihoods, in contrast with the land laws that allows a compensation amount that would put previous land users in a better or the same wellbeing as before the land expropriation. In addition, it is indicated that the land expropriation process does not take into account the value of ecosystem services, which are benefits obtain from the land, and important for the wellbeing of the society. We conclude that while land expropriation is an important tool to obtain land from the landholders when it is needed for public purposes, the practices in the study area show it is adversely affecting the socioeconomics of farmers and the environment.
Keywords: Doctoral thesis; Engineering Management (ENM)
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“Social sustainability assessments in the biobased economy : towards a systemic approach”. Rafiaani P, Kuppens T, Van Dael M, Azadi H, Lebailly P, Van Passel S, Renewable &, Sustainable Energy Reviews 82, 1839 (2018). http://doi.org/10.1016/J.RSER.2017.06.118
Abstract: The majority of impact assessments for the biobased economy are primarily focused on the environmental and (techno-)economic aspects, while social aspects are rarely considered. This study proposes a modified systemic approach for a social sustainability impact assessment of the biobased economy, based on a review on the common methodologies for assessing social impacts. Accordingly, the proposed approach follows the four general iterative steps of social life cycle analysis (SLCA) as it considers all life cycle phases of the biobased economy. The systemic approach considers the potential social impacts on local communities, workers, and consumers as the main three groups of the stakeholders. The review showed that the most common social indicators for inventory analysis within the biobased economy include health and safety, food security, income, employment, land- and worker-related concerns, energy security, profitability, and gender issues. Multi-criteria decision analysis (MCDA) was also highlighted as the broadly utilized methodology for aggregating the results of impact assessments within the biobased economy. Taking a life cycle perspective, this study provides a holistic view of the full sustainability of research, design, and innovation in the biobased economy by suggesting the integration of the social aspects with techno-economic and an environmental life cycle assessment. Our proposed systemic approach makes possible to integrate the social impacts that are highly valued by the affected stakeholders into the existing sustainability models that focus only on environmental and techno-economic aspects. We discuss the steps of the proposed systemic approach in order to identify the challenges of applying them within the biobased economy. These challenges refer mainly to the definition of the functional unit and system boundaries, the selection and the analysis of social indicators (inventory analysis), the aggregation of the inventory to impact categories, and the uncertainties associated with the social sustainability evaluation. The result of this review and the proposed systemic approach serve as a foundation for industry and policy makers to gain a better insight into the importance of social sustainability impacts assessment within the biobased economy.
Keywords: A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM)
Impact Factor: 8.05
Times cited: 28
DOI: 10.1016/J.RSER.2017.06.118
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“Social risk screening using a socio-political ambiguity approach : the case of organic agriculture in Iran”. Mahmoudi H, Renn O, Hoffmann V, Van Passel S, Azadi H, Journal Of Risk Research 18, 747 (2015). http://doi.org/10.1080/13669877.2014.910696
Keywords: A1 Journal article; Sociology; Engineering Management (ENM)
Impact Factor: 1.34
Times cited: 1
DOI: 10.1080/13669877.2014.910696
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“SnIV-containing layered double hydroxides as precursors for nano-sized ZnO/SnO2 photocatalysts”. Seftel EM, Popovici E, Mertens M, Stefaniak EA, Van Grieken R, Cool P, Vansant EF, Applied catalysis : B : environmental 84, 699 (2008). http://doi.org/10.1016/J.APCATB.2008.06.006
Abstract: Sn4+-containing LDH was prepared using the co-precipitation method at constant pH, and characterized using X-ray diffraction, UVvis diffuse reflectance spectroscopy and TG/DTG methods. The obtained product was further exposed to different thermal treatments in order to obtain nano-sized coupled ZnO/SnO2 systems with enhanced photocatalytic performances than the ones obtained by mixing the two semiconductor oxides. The formation of a well-defined ZnO/SnO2 system and the crystallite size, fully investigated using XRD, micro-Raman scattering and UVvis DR techniques, were found to be influenced by the nature of the precursors and the calcination temperature. The photocatalytic activity of the ZnO/SnO2 systems, evaluated for the photodegradation of methyl orange (MO) dye, was studied as a function of the initial pH, catalyst loading and the calcination temperature. The metal dispersion supplied by layered structures proved to be an advantage when preparing coupled ZnO/SnO2 systems, the photocatalytic activity being 2.3 times higher comparing with the physical mixtures performances. The maximum photocatalytic activity of the coupled ZnO/SnO2 system having a layered precursor was observed when using neutral pH, at a catalyst loading of 1 g/L calcined at 600 °C for 4 h.
Keywords: A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.APCATB.2008.06.006
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“Sn20.5-3.5As22I8: a largely disordered cationic clathrate with a new type of superstructure and abnormally low thermal conductivity”. Zaikina JV, Kovnir KA, Sobolev AV, Presniakov IA, Prots Y, Baitinger M, Schnelle W, Olenev AV, Lebedev OI, Van Tendeloo G, Grin Y, Shevelkov AV, Chemistry: a European journal 13, 5090 (2007). http://doi.org/10.1002/chem.200601772
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 5.317
Times cited: 44
DOI: 10.1002/chem.200601772
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“Sn2-2xSbxFexO4 solid solutions as possible inert anode materials in aluminum electrolysis”. Govorov VA, Abakumov AM, Rozova MG, Borzenko AG, Vassiliev SY, Mazin VM, Afanasov MI, Fabritchnyi PB, Tsirlina GA, Antipov EV, Morozova EN, Gippius AA, Ivanov VV, Van Tendeloo G, Chemistry of materials 17, 3004 (2005). http://doi.org/10.1021/cm048145i
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 11
DOI: 10.1021/cm048145i
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“Sn19.3Cu4.7As22I8: a new clathrate-I compound with transition-metal atoms in the cationic framework”. Kovnir KA, Sobolev AV, Presniakov IA, Lebedev OI, Van Tendeloo G, Schnelle W, Grin Y, Shevelkov AV, Inorganic chemistry 44, 8786 (2005). http://doi.org/10.1021/ic051160k
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.857
Times cited: 38
DOI: 10.1021/ic051160k
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“Snake states in graphene quantum dots in the presence of a p-n junction”. Zarenia M, Pereira JM Jr, Peeters FM, Farias GA, Physical review : B : condensed matter and materials physics 87, 035426 (2013). http://doi.org/10.1103/PhysRevB.87.035426
Abstract: We investigate the magnetic interface states of graphene quantum dots that contain p-n junctions. Within a tight-binding approach, we consider rectangular quantum dots in the presence of a perpendicular magnetic field containing p-n as well as p-n-p and n-p-n junctions. The results show the interplay between the edge states associated with the zigzag terminations of the sample and the snake states that arise at the p-n junction due to the overlap between electron and hole states at the potential interface. Remarkable localized states are found at the crossing of the p-n junction with the zigzag edge having a dumb-bell-shaped electron distribution. The results are presented as a function of the junction parameters and the applied magnetic flux. DOI: 10.1103/PhysRevB.87.035426
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 16
DOI: 10.1103/PhysRevB.87.035426
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“Snake states and Klein tunneling in a graphene Hall bar with a pn-junction”. Barbier M, Papp G, Peeters FM, Applied physics letters 100, 163121 (2012). http://doi.org/10.1063/1.4704667
Abstract: The Hall (R-H) and bend (R-B) resistances of a graphene Hall bar structure containing a pn-junction are calculated when in the ballistic regime. The simulations are done using the billiard model. Introducing a pn-junction-dividing the Hall bar geometry in two regions-leads to two distinct regimes exhibiting very different physics: (1) both regions are of n-type and (2) one region is n-type and the other p-type. In regime (1), a “Hall plateau”-an enhancement of the resistance-appears for R-H. On the other hand, in regime (2), we found a negative R-H, which approaches zero for large B. The bend resistance is highly asymmetric in regime (2) and the resistance increases with increasing magnetic field B in one direction while it reduces to zero in the other direction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704667]
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 20
DOI: 10.1063/1.4704667
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