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Records |
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Author |
Simoen, E.; Loo, R.; Claeys, C.; de Gryse, O.; Clauws, P.; van Landuyt, J.; Lebedev, O. |
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Title |
Optical spectroscopy of oxygen precipitates in heavily doped p-type silicon |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Journal of physics : condensed matter
T2 – Conference on Extended Defects in Semiconductors (EDS 2002), JUN 01-06, 2002, BOLOGNA, ITALY |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
14 |
Issue |
48 |
Pages |
13185-13193 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Results are presented on the photoluminescence (PL) characterization of heavily doped p(+) Czochralski silicon, which has been subjected to a two-step, oxygen precipitation heat treatment. It will be shown that the presence of oxygen precipitates gives rise to the D1, D2 and D5 lines, where the energy of the D1 line shifts to lower values for a stronger degree of precipitation. The occurrence of these PL features is also a function of the boron concentration in the p(+) material. The PL results are compared with Fourier transform infrared absorption data and with transmission electron microscope, results. From this, it is concluded that PL has a good potential for use in the assessment of oxygen precipitation in heavily doped silicon. |
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Corporate Author |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000180091100068 |
Publication Date |
2002-11-23 |
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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 |
0953-8984; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.649; 2002 IF: 1.775 |
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Call Number |
UA @ lucian @ c:irua:103326 |
Serial |
2477 |
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Permanent link to this record |
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Author |
Cassiers, K.; van der Voort, P.; Linssen, T.; Vansant, E.F.; Lebedev, O.; van Landuyt, J. |
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Title |
A counterion-catalyzed (S0H+)(X-I+) pathway toward heat- and steam-stable mesostructured silica assembled from amines in acidic conditions |
Type |
A1 Journal article |
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Year |
2003 |
Publication |
The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical |
Abbreviated Journal |
J Phys Chem B |
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Volume |
107 |
Issue |
16 |
Pages |
3690-3696 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
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Abstract |
An alternative pathway to assemble mesoporous molecular sieve silicas is developed using nonionic alkylamines and N,N-dimethylalkylamines (SO) as structure-directing agents in acidic conditions. The synthesized mesostructures possess wormhole-like frameworks with pore sizes and pore volumes in the range of 20-90 Angstrom and 0.5-1.3 cm(3)/g, respectively. The formation of the mesophase is controlled by a counterion-mediated mechanism of the type (S(0)H(+))(X(-)I(+)), where S(0)H(+) are protonated water molecules that are hydrogen bonded to the lone electron pairs on the amine surfactant headgroups (S(0)H(+)), X(-) is the counteranion originating from the acid, and I(+) are the positively charged (protonated) silicate species. We found that the stronger the ion X(-) is bonded to S(0)H(+), the more it catalyzes the silica condensation into (S(0)H(+))(X(-)I(+)). Br(-) is shown to be a strong binding anion and therefore a fast silica polymerization promoter compared to Cl(-) resulting in the formation of a higher quality mesophase for the Br(-) syntheses. We also showed that the polymerization rate of the silica, dictated by the counterion, controls the morphology of the mesostructures from nonuniform agglomerated blocks in the case of Br(-) syntheses to spherical particles for the Cl(-) syntheses. Next to many benefits such as low temperature, short synthesis time, and the use of inexpensive, nontoxic, and easily extractable amine templates, the developed materials have a remarkable higher thermal and hydrothermal stability compared to hexagonal mesoporous silica, which is also prepared with nonionic amines but formed through the S(0)I(0) mechanism. |
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Corporate Author |
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Thesis |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000182350200005 |
Publication Date |
2003-04-17 |
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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 |
1520-6106;1520-5207; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.177 |
Times cited |
9 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.177; 2003 IF: 3.679 |
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Call Number |
UA @ lucian @ c:irua:103300 |
Serial |
24 |
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Permanent link to this record |
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Author |
Linssen, T.; Cassiers, K.; Cool, P.; Lebedev, O.; Whittaker, A.; Vansant, E.F. |
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Title |
Physicochemical and structural characterization of mesoporous aluminosilicates synthesized from leached saponite with additional aluminum incorporation |
Type |
A1 Journal article |
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Year |
2003 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
15 |
Issue |
25 |
Pages |
4863-4873 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
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Abstract |
A thorough investigation was performed on the physical (mechanical, thermal, and hydrothermal stability) and chemical (ion exchange capacity and silanol number) characteristics of aluminosilicate FSMs, synthesized via a new successful short-time synthesis route using leached saponite and a low concentration of CTAB. Moreover, the influence of an additional Al incorporation, utilizing different aluminum sources, on the structure of the FSM derived from saponite is studied. A mesoporous aluminosilicate with a low Si/Al ratio of 12.8 is synthesized, and still has a very large surface area of 1130 m(2)/g and pore volume of 0.92 cm(3)/g. The aluminum-containing samples all have a high cation exchange capacity of around 1 mmol/9 while they still have a silanol number of about 0.9 OH/nm(2); both characteristics being interesting for high-yield postsynthesis modification reactions. Finally, a study is performed on the transformation of the aluminosilicates into their Bronsted acid form via the exchange with ammonium ions and a consecutive heat treatment. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000187250800026 |
Publication Date |
2003-12-09 |
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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 |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 9.466; 2003 IF: 4.374 |
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Call Number |
UA @ lucian @ c:irua:103265 |
Serial |
2618 |
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Permanent link to this record |
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Author |
Laffez, P.; Lebedev, O.I.; Ruello, P.; Desfeux, R.; Banerjee, G.; Capon, F. |
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Title |
Evidence of strain induced structural change in hetero-epitaxial NdNiO3 thin films with metal-insulator transition |
Type |
A1 Journal article |
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Year |
2004 |
Publication |
European physical journal: applied physics |
Abbreviated Journal |
Eur Phys J-Appl Phys |
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Volume |
25 |
Issue |
1 |
Pages |
25-31 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Neodymium nickelate thin films have been prepared on NdGaO3 substrates by RF magnetron sputtering and post-annealing treatment under oxygen pressure. Transport properties are found to depend strongly on film thickness. Thick films show transport properties close to bulk ceramics, while very thin films exhibit a large transition from metal to insulator which occurs over a wide temperature range with high resistivity. Structure and surface morphology of the films have been investigated by Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). Thin films (approximate to17 nm) grow heteroepitaxially, while thicker films (approximate to73 nm) show a granular structure. The thinnest sample suggests a symmetry change induced by the epitaxial strain of the substrate. This paper discusses the relationship between microstructure and transport properties. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Paris |
Editor |
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Language |
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Wos |
000187286000003 |
Publication Date |
2003-12-15 |
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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 |
1286-0042;1286-0050; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
0.684 |
Times cited |
12 |
Open Access |
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Notes |
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Approved |
Most recent IF: 0.684; 2004 IF: 0.745 |
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Call Number |
UA @ lucian @ c:irua:103256 |
Serial |
1096 |
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Permanent link to this record |
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Author |
Mahieu, S.; Ghekiere, P.; de Winter, G.; de Gryse, R.; Depla, D.; Lebedev, O.I. |
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Title |
Biaxially aligned yttria stabilized zirconia and titanium nitride layers deposited by unbalanced magnetron sputtering |
Type |
A1 Journal article |
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Year |
2005 |
Publication |
Diffusion and defect data : solid state data : part B : solid state phenomena
T2 – 2nd International Conference on Texture and Anisotropy of Polycrystals, JUL 07-09, 2004, Metz, FRANCE |
Abbreviated Journal |
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Volume |
105 |
Issue |
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Pages |
447-452 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Control of the texture and the biaxial alignment of sputter deposited films has provoked a great deal of interest due to its technological importance. indeed, many physical properties of thin films are influenced by the biaxial alignment. In this context, extensive research has been established to understand the growth mechanism of biaxially aligned Yttria Stabilized Zirconia (YSZ) as a buffer layer for high temperature superconducting copper oxides. In this work, the growth mechanism in general and the mechanism responsible of the biaxial alignment in detail were investigated for thin films of YSZ and TiN deposited by unbalanced magnetron sputtering using non-aligned polycrystalline stainless steel substrates. The mechanism responsible for the preferential out-of-plane alignment has been investigated by performing depositions on a non-tilted substrate. However, to study the in-plane alignment a tilted substrate was used. The microstructure of the deposited layers was characterised by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The crystallographic alignment has been investigated by X-ray diffraction (XRD) (angular scans and pole figures) and by Selective Area Diffraction (SAD). It was observed that the deposited layers show a zone T or zone II structure and the layers with a zone T structure consist of faceted grains. There seems to be a correlation between the crystal habit of these faceted grains and the measured biaxial alignment. A model for the preferential out-of-plane orientation, the in-plane alignment and the correlation between the microstructure and the biaxial alignment is proposed. |
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Corporate Author |
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Publisher |
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Place of Publication |
Vaduz |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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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 |
3-908451-09-4 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:103190 |
Serial |
230 |
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Permanent link to this record |
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Author |
Verbist, K.; Lebedev, O.I.; Van Tendeloo, G.; Verhoeven, M.A.J.; Rijnders, A.J.H.M.; Blank, D.H.A. |
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Title |
Study of ramp-type Josephson junctions by HREM |
Type |
A1 Journal article |
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Year |
1997 |
Publication |
Electronic Applications; Vol 2: Large Scale And Power Applications |
Abbreviated Journal |
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Volume |
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Issue |
158 |
Pages |
49-52 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Structural aspects of ramp-type Josephson junctions based on REBa2Cu3O7-delta high-T-c superconductors, are investigated by cross-section transmission electron microscopy and results related to fabrication process or physical properties. The barrier layer material is PrBa2Cu3-xGaxO7-delta. The ramp-geometry depends on the etching conditions. High levels of Ga doping (x>0.7) influence the microstructure of the barrier layer thereby changing the junctions properties. |
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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 |
000071955200012 |
Publication Date |
0000-00-00 |
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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 |
0-7503-0487-1 |
ISBN |
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Additional Links |
UA library record; WoS full record; |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:102941 |
Serial |
3333 |
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Permanent link to this record |
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Author |
Verbist, K.; Lebedev, O.I.; Van Tendeloo, G.; Tafuri, F.; Granozio, F.M.; Di Chiara, A.; Bender, H. |
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Title |
A potential method to correlate electrical properties and microstructure of a unique high-Tc superconducting Josephson junction |
Type |
A1 Journal article |
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Year |
1999 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
74 |
Issue |
7 |
Pages |
1024-1026 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A method to correlate microstructure from cross-section transmission electron microscopy (TEM) investigations and transport properties of a single well characterized high-T-c artificial grain boundary junction is reported. A YBa2Cu3O7-delta 45 degrees twist junction exhibiting the typical phenomenology of high T-c Josephson weak links was employed. The TEM sample preparation is based on focused ion beam etching and allows to easily localize the electron transparent area on a microbridge. The reported technique opens clear perspectives in the determination of the microstructural origin of variations in Josephson junction properties, such as the spread in I-c and IcRN values and the presence of different transport regimes in nominally identical junctions. (C) 1999 American Institute of Physics. [S0003-6951(99)03404-X]. |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000078571400043 |
Publication Date |
2002-07-26 |
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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 |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
5 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 1999 IF: 4.184 |
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Call Number |
UA @ lucian @ c:irua:102912 |
Serial |
2686 |
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Permanent link to this record |
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Author |
Farvacque, J.L.; Bougrioua, Z.; Moerman, I.; Van Tendeloo, G.; Lebedev, O. |
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Title |
Role of the defect microstructure on the electrical transport properties in undoped and Si-doped GaN grown by LP-MOVPE |
Type |
A1 Journal article |
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Year |
1999 |
Publication |
Physica: B : condensed matter
T2 – 20th International Conference on Defects in Semiconductors (ICDS-20), JUL 26-30, 1999, BERKELEY, CA |
Abbreviated Journal |
Physica B |
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Volume |
273-4 |
Issue |
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Pages |
140-143 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Experimental results show that the room-temperature carrier mobility in bulk layers of undoped or Si-doped GaN grown by LP-MOVPE on sapphire substrate shows a sudden increase as soon as the carrier density exceeds a critical value of about 10(18) cm(-3). We show that such a behavior can be theoretically reproduced by assuming that the columnar structure i.e. the dislocation microstructure is responsible for internal electronic barriers. (C) 1999 Elsevier Science B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000084452200031 |
Publication Date |
2002-07-26 |
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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 |
0921-4526; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.386 |
Times cited |
5 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.386; 1999 IF: 0.725 |
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Call Number |
UA @ lucian @ c:irua:102892 |
Serial |
2925 |
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Permanent link to this record |
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Author |
Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerof, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.; Park, Y.W. |
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Title |
The superconducting bismuth-based mixed oxides |
Type |
A1 Journal article |
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Year |
2003 |
Publication |
Journal of low temperature physics
T2 – International Conference on Physics and Chemistry of Molecular and Oxide, Superconductors (MOS2002), AUG 13-18, 2002, HSINCHU, TAIWAN |
Abbreviated Journal |
J Low Temp Phys |
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Volume |
131 |
Issue |
3-4 |
Pages |
575-587 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The present paper describes the synthesis, characterization of mixed-valence bismuthates with 3- or 2-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12K exists in the narrow range (x approximate to 0.5 – 0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the 3-dimensional octahedral framework has close to the ideal perovskite structure arrangement. At the same time compositions with close to optimal Bi-valence (x = 0.33 and 0.43) do not show any sign of superconductivity, probably, due to structural distortions. The layered type (BaK)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated Buckling of the (BiO2) layers in the structure of the n = 2 member was revealed The formation of the n=1 bismuthate was found by Electron Microscopy and X-ray powder diffraction studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
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Language |
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Wos |
000181768000061 |
Publication Date |
2003-04-07 |
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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 |
0022-2291; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.3 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.3; 2003 IF: 1.171 |
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Call Number |
UA @ lucian @ c:irua:102803 |
Serial |
3597 |
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Permanent link to this record |
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Author |
Paul, J.S.; Groothaert, M.H.; Kirschhock, C.E.A.; Lebedev, O.I.; Jacobs, P.A.; Maier, W.F. |
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Title |
Novel MoVSbOx-type catalysts for selective isobutane oxidation |
Type |
A1 Journal article |
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Year |
2004 |
Publication |
Catalysis today
T2 – 7th European Workshop Meeting on Selective Oxidation, AUG 31-SEP 04, 2003, Innsbruck, AUSTRIA |
Abbreviated Journal |
Catal Today |
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Volume |
91-2 |
Issue |
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Pages |
265-269 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A new sol-gel synthesis procedure is proposed for the preparation of MoVSbOx catalysts for the selective oxidation of isobutane. Physico-chemical characterization of the materials calcined at 400 degreesC, showed essentially amorphous catalysts, with long-range order. Increase of calcination temperature, however, resulted in the formation of small crystalline regions, confirmed through TEM. EPR measurements on the calcined samples pointed to the presence of isolated and magnetically interacting V(IV) species. The reported catalysts proved to be much more selective for partial oxidation compared to a literature reference catalyst. Furthermore, it is shown that this versatile synthesis recipe forms an excellent start for high-throughput and combinatorial studies. (C) 2004 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000222691000049 |
Publication Date |
2004-05-11 |
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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 |
0920-5861; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.636 |
Times cited |
12 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.636; 2004 IF: 3.108 |
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Call Number |
UA @ lucian @ c:irua:102761 |
Serial |
2383 |
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Permanent link to this record |
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Author |
Godefroo, S.; Hayne, M.; Jivanescu, M.; Stesmans, A.; Zacharias, M.; Lebedev, O.I.; Van Tendeloo, G.; Moshchalkov, V.V. |
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Title |
Classification and control of the origin of photoluminescence from Si nanocrystals |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
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Volume |
3 |
Issue |
3 |
Pages |
174-178 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Silicon dominates the electronics industry, but its poor optical properties mean that III-V compound semiconductors are preferred for photonics applications. Photoluminescence at visible wavelengths was observed from porous Si at room temperature in 1990, but the origin of these photons (do they arise from highly localized defect states or quantum confinement effects?) has been the subject of intense debate ever since. Attention has subsequently shifted from porous Si to Si nanocrystals, but the same fundamental question about the origin of the photoluminescence has remained. Here we show, based on measurements in high magnetic fields, that defects are the dominant source of light from Si nanocrystals. Moreover, we show that it is possible to control the origin of the photoluminescence in a single sample: passivation with hydrogen removes the defects, resulting in photoluminescence from quantum-confined states, but subsequent ultraviolet illumination reintroduces the defects, making them the origin of the light again. |
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Publisher |
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Place of Publication |
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Wos |
000254743600017 |
Publication Date |
2008-03-02 |
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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 |
1748-3387;1748-3395; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
38.986 |
Times cited |
426 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 38.986; 2008 IF: 20.571 |
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Call Number |
UA @ lucian @ c:irua:102630 |
Serial |
373 |
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Permanent link to this record |
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Author |
Maignan, A.; Martin, C.; Singh, K.; Simon, C.; Lebedev, O.I.; Turner, S. |
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Title |
From spin induced ferroelectricity to dipolar glasses : spinel chromites and mixed delafossites |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
195 |
Issue |
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Pages |
41-49 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Magnetoelectric multiferroics showing coupling between polarization and magnetic order are attracting much attention. For instance, they could be used in memory devices. Metal-transition oxides are provided several examples of inorganic magnetoelectric multiferroics. In the present short review, spinel and delafossite chromites are described. For the former, an electric polarization is evidenced in the ferrimagnetic state for ACr2O4 polycrystalline samples (A=Ni, Fe, Co). The presence of a JahnTeller cation such as Ni2+ at the A site is shown to yield larger polarization values. In the delafossites, substitution by V3+ at the Cr or Fe site in CuCrO2 (CuFeO2) suppresses the complex antiferromagnetic structure at the benefit of a spin glass state. The presence of cation disorder, probed by transmission electron microscopy, favors relaxor-like ferroelectricity. The results on the ferroelectricity of ferrimagnets and insulating spin glasses demonstrate that, in this research field, transition-metal oxides are worth to be studied. |
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Place of Publication |
London |
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Wos |
000309783600006 |
Publication Date |
2012-02-09 |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
27 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 2.299; 2012 IF: 2.040 |
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Call Number |
UA @ lucian @ c:irua:101219 |
Serial |
1286 |
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Permanent link to this record |
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Author |
Bigiani, L.; Barreca, D.; Gasparotto, A.; Andreu, T.; Verbeeck, J.; Sada, C.; Modin, E.; Lebedev, O.I.; Morante, J.R.; Maccato, C. |
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Title |
Selective anodes for seawater splitting via functionalization of manganese oxides by a plasma-assisted process |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Applied Catalysis B-Environmental |
Abbreviated Journal |
Appl Catal B-Environ |
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Volume |
284 |
Issue |
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Pages |
119684 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The electrolysis of seawater, a significantly more abundant natural reservoir than freshwater, stands as a promising alternative for sustainable hydrogen production, provided that the competitive chloride electro-oxidation is minimized. Herein, we propose an original material combination to selectively trigger oxygen evolution from seawater at expenses of chlorine generation. The target systems, based on MnO2 or Mn2O3 decorated with Fe2O3 or Co3O4, are fabricated by plasma enhanced-chemical vapor deposition of manganese oxides, functionalization with Fe2O3 and Co3O4 by sputtering, and annealing in air/Ar to obtain Mn(IV)/Mn(III) oxides. Among the various options, MnO2 decorated with Co3O4 yields the best performances in alkaline seawater splitting, with an outstanding Tafel slope of approximate to 40 mV x dec(-1) and an overpotential of 450 mV, enabling to rule out chlorine evolution. These attractive performances, resulting from the synergistic contribution of catalytic and electronic effects, open the door to low-cost hydrogen generation from seawater under real-world conditions, paving the way to eventual large-scale applications. |
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Place of Publication |
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Wos |
000623591500008 |
Publication Date |
2020-11-20 |
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Series Editor |
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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 |
0926-3373 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.446 |
Times cited |
67 |
Open Access |
OpenAccess |
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Notes |
The authors thank Padova University (DOR 2017–2020 and P-DiSC #03BIRD2018-UNIPD OXYGENA projects), as well as the INSTM Consortium (INSTMPD004 – NETTUNO project) and AMGA Foundation (Mn4Energy project), for financial support. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. J.V. acknowledges funding from a GOA project 'Solarpaint' (University of Antwerp) and from the EU-H2020 programme (grant agreement No. 823717 – ESTEEM3). J.R.M. and T.A. acknowledge Generalitat de Catalunya for financial support through the CERCA Programme, 27 M2E (2017SGR1246) and by ERDEF-MINECO coordinated projects ENE2017-85087-C3 and ENE2016-80788-C5-5-R. Thanks are also due to Proff. Gloria Tabacchi and Ettore Fois (Department of Science and High Technology, Insubria University, Como, Italy) for valuable discussions and support. Dr. Daniele Valbusa, Dr. Gianluca Corrò, Dr. Andrea Gallo and Dr. Dileep Khrishnan are gratefully acknowledged for helpful technical assistance. |
Approved |
Most recent IF: 9.446 |
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Call Number |
UA @ admin @ c:irua:176718 |
Serial |
6733 |
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Permanent link to this record |
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Author |
Bigiani, L.; Gasparotto, A.; Andreu, T.; Verbeeck, J.; Sada, C.; Modin, E.; Lebedev, O.I.; Morante, J.R.; Barreca, D.; Maccato, C. |
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Title |
Au-manganese oxide nanostructures by a plasma-assisted process as electrocatalysts for oxygen evolution : a chemico-physical investigation |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Advanced sustainable systems |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
2000177-11 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Earth-abundant and eco-friendly manganese oxides are promising platforms for the oxygen evolution reaction (OER) in water electrolysis. Herein, a versatile and potentially scalable route to gold-decorated manganese oxide-based OER electrocatalysts is reported. In particular, MnxOy(MnO2, Mn2O3) host matrices are grown on conductive glasses by plasma assisted-chemical vapor deposition (PA-CVD), and subsequently functionalized with gold nanoparticles (guest) as OER activators by radio frequency (RF)-sputtering. The final selective obtainment of MnO2- or Mn2O3-based systems is then enabled by annealing under oxidizing or inert atmosphere, respectively. A detailed material characterization evidences the formation of high-purity Mn(x)O(y)dendritic nanostructures with an open morphology and an efficient guest dispersion into the host matrices. The tailoring of Mn(x)O(y)phase composition and host-guest interactions has a remarkable influence on OER activity yielding, for the best performing Au/Mn(2)O(3)system, a current density of approximate to 5 mA cm(-2)at 1.65 V versus the reversible hydrogen electrode (RHE) and an overpotential close to 300 mV at 1 mA cm(-2). Such results, comparing favorably with literature data on manganese oxide-based materials, highlight the importance of compositional control, as well as of surface and interface engineering, to develop low-cost and efficient anode nanocatalysts for water splitting applications. |
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Wos |
000572376000001 |
Publication Date |
2020-09-25 |
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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 |
2366-7486 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
7.1 |
Times cited |
4 |
Open Access |
Not_Open_Access |
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Notes |
; Padova University (DOR 2017-2019 and P-DiSC #03BIRD2018-UNIPD OXYGENA projects), as well as the INSTM Consortium (INSTMPD004 – NETTUNO project) and AMGA Foundation (Mn4Energy project), are gratefully acknowledged for financial support. The Qu-Ant-EM microscope was partially funded by the Hercules fund from the Flemish Government. J.V. acknowledges funding from a GOA project “Solarpaint” from the University of Antwerp and from EU H2020 823717 ESTEEM3 project. The authors thank Dr. Daniele Valbusa, Dr. Gianluca Corr, Dr. Andrea Gallo, and Dr. Dileep Khrishnan for helpful experimental assistance. ; esteem3TA; esteem3reported |
Approved |
Most recent IF: 7.1; 2020 IF: NA |
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Call Number |
UA @ admin @ c:irua:171937 |
Serial |
6457 |
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Permanent link to this record |