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	Author	Zhang, H.; Yang, J.-H.; Shpanchenko, R.V.; Abakumov, A.M.; Hadermann, J.; Clérac, R.; Dikarev, E.V.
	Title	New class of single-source precursors for the synthesis of main group-transition metal oxides: heterobimetallic Pb-Mn \beta-diketonates			Type	A1 Journal article
	Year	2009	Publication	Inorganic chemistry	Abbreviated Journal	Inorg Chem
	Volume	48	Issue	17	Pages	8480-8488
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Heterometallic lead−manganese â-diketonates have been isolated in pure form by several synthetic methods that include solid-state and solution techniques. Two compounds with different Pb/Mn ratios, PbMn2(hfac)6 (1) and PbMn(hfac)4 (2) (hfac = hexafluoroacetylacetonate), can be obtained in quantitative yield by using different starting materials. Single crystal X-ray investigation revealed that the solid-state structure of 1 contains trinuclear molecules in which lead metal center is sandwiched between two [Mn(hfac)3] units, while 2 consists of infinite chains of alternating [Pb(hfac)2] and [Mn(hfac)2] fragments. The heterometallic structures are held together by strong Lewis acid−base interactions between metal atoms and diketonate ligands acting in chelating-bridging fashion. Spectroscopic investigation confirmed the retention of heterometallic structures in solutions of non-coordinating solvents as well as upon sublimation-deposition procedure. Thermal decomposition of heterometallic diketonates has been systematically investigated in a wide range of temperatures and annealing times. For the first time, it has been shown that thermal decomposition of heterometallic diketonates results in mixed-metal oxides, while both the structure of precursors and the thermolysis conditions have a significant influence on the nature of the resulting oxides. Five different Pb−Mn oxides have been detected by X-ray powder diffraction when studying the decomposition of 1 and 2 in the temperature range 500−800 °C. The phase that has been previously reported as Pb0.43MnO2.18 was synthesized in the pure form by decomposition of 1, and crystallographically characterized. The orthorhombic unit cell parameters of this oxide, obtained by electron diffraction technique, have been subsequently refined using X-ray powder diffraction data. Besides that, a previously unknown lead−manganese oxide has been obtained at low temperature decomposition and short annealing times. The parameters of its monoclinically distorted unit cell have been determined. The EDX analysis revealed that this compound has a Pb/Mn ratio close to 1:4 and contains no appreciable amount of fluorine.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Easton, Pa	Editor
	Language		Wos	000269313500056	Publication Date	2009-08-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0020-1669;1520-510X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.857	Times cited	28	Open Access
	Notes				Approved	Most recent IF: 4.857; 2009 IF: 4.657
	Call Number	UA @ lucian @ c:irua:78486			Serial	2308
Permanent link to this record



	Author	Zhang, F.; Vanmeensel, K.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Van Meerbeek, B.; Naert, I.; Vleugels, J.
	Title	3Y-TZP ceramics with improved hydrothermal degradation resistance and fracture toughness			Type	A1 Journal article
	Year	2014	Publication	Journal of the European Ceramic Society	Abbreviated Journal	J Eur Ceram Soc
	Volume	34	Issue	10	Pages	2453-2463
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Different factors such as the way of incorporating the Y2O3 stabilizer, alumina addition and sintering temperature were assessed with the goal to improve the low temperature degradation (LTD) resistance of 3Y-TZP without compromising on the mechanical properties. The degradation of hydrothermally treated specimens was studied by X-ray diffraction, micro-Raman spectroscopy and scanning electron microscopy. Decreasing the sintering temperature decreased the LTD susceptibility of 3Y-TZPs but did not allow to obtain a LTD resistant 3Y-TZP with optimized mechanical properties. Alumina addition along with the use of Y2O3 stabilizer coated starting powder allowed to combine both an excellent toughness and LTD resistance, as compared to alumina-free and stabilizer co-precipitated powder based equivalents. Transmission electron microscopy revealed that the improved LTD resistance could be attributed to the segregation of Al3+ at the grain boundary and the heterogeneously distributed Y3+ stabilizer.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Barking	Editor
	Language		Wos	000336352500033	Publication Date	2014-03-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0955-2219;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	48	Open Access
	Notes	Fwo G.0431.10n			Approved	Most recent IF: 3.411; 2014 IF: 2.947
	Call Number	UA @ lucian @ c:irua:117065 c:irua:117065			Serial	11
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	Author	Zhang, F.; Vanmeensel, K.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Van Meerbeek, B.; Naert, I.; Vleugels, J.
	Title	Critical influence of alumina content on the low temperature degradation of 2-3 mol% yttria-stabilized TZP for dental restorations			Type	A1 Journal article
	Year	2015	Publication	Journal of the European Ceramic Society	Abbreviated Journal	J Eur Ceram Soc
	Volume	35	Issue	35	Pages	741-750
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The influence of 0.25, 2 and 5 wt.% alumina addition on the mechanical properties and low temperature degradation (LTD) of 3, 2.5 and 2 mol% yttria-stabilized TZP ceramics was investigated. The amount of alumina addition was observed to have a crucial impact on the degradation of Y-TZP ceramics. Independent on the yttria stabilizer content, 0.25 wt.% alumina had a higher degradation retarding effect to Y-TZP ceramics than 2 and 5 wt.% of alumina addition, which had a comparable effect. The apparent activation energy for the degradation process was increased by adding alumina, but it was the same for 0.255 wt.% alumina doped 3Y-TZP ceramics. For Y-TZPs containing a small amount of alumina addition, only the segregated Al3+ at the grain boundaries of the zirconia grains was effective to retard the degradation of Y-TZPs. The secondary phase Al2O3 grains increased the degradation kinetics, which might be attributed to the residual stresses.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Barking	Editor
	Language		Wos	000345201700032	Publication Date	2014-09-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0955-2219;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	37	Open Access
	Notes	Fwo G043110n			Approved	Most recent IF: 3.411; 2015 IF: 2.947
	Call Number	c:irua:121328			Serial	544
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	Author	Zhang, F.; Vanmeensel, K.; Batuk, M.; Hadermann, J.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J.
	Title	Highly-translucent, strong and aging-resistant 3Y-TZP ceramics for dental restoration by grain boundary segregation			Type	A1 Journal article
	Year	2015	Publication	Acta biomaterialia	Abbreviated Journal	Acta Biomater
	Volume	16	Issue	16	Pages	215-222
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Latest trends in dental restorative ceramics involve the development of full-contour 3Y-TZP ceramics which can avoid chipping of veneering porcelains. Among the challenges are the low translucency and the hydrothermal stability of 3Y-TZP ceramics. In this work, different trivalent oxides (Al2O3, Sc2O3, Nd2O3 and La2O3) were selected to dope 3Y-TZP ceramics. Results show that dopant segregation was a key factor to design hydrothermally stable and high-translucent 3Y-TZP ceramics and the cation dopant radius could be used as a controlling parameter. A large trivalent dopant, oversized as compared to Zr4+, exhibiting strong segregation at the ZrO2 grain boundary was preferred. The introduction of 0.2 mol% La2O3 in conventional 0.10.25 wt.% Al2O3-doped 3Y-TZP resulted in an excellent combination of high translucency and superior hydrothermal stability, while retaining excellent mechanical properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	S.l.	Editor
	Language		Wos	000351978600021	Publication Date	2015-02-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1742-7061;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.319	Times cited	54	Open Access
	Notes	Fwo G043110n			Approved	Most recent IF: 6.319; 2015 IF: 6.025
	Call Number	c:irua:124421			Serial	1473
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	Author	Zhang, F.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Naert, I.; Van Meerbeek, B.; Vleugels, J.
	Title	Strength, toughness and aging stability of highly-translucent Y-TZP ceramics for dental restorations			Type	A1 Journal article
	Year	2016	Publication	Dental Materials	Abbreviated Journal	Dent Mater
	Volume	32	Issue	32	Pages	e327-e337
	Keywords	A1 Journal article; Electron Microscopy for Materials Science (EMAT);
	Abstract	OBJECTIVE: The aim was to evaluate the optical properties, mechanical properties and aging stability of yttria-stabilized zirconia with different compositions, highlighting the influence of the alumina addition, Y2O3 content and La2O3 doping on the translucency. METHODS: Five different Y-TZP zirconia powders (3 commercially available and 2 experimentally modified) were sintered under the same conditions and characterized by X-ray diffraction with Rietveld analysis and scanning electron microscopy (SEM). Translucency (n=6/group) was measured with a color meter, allowing to calculate the translucency parameter (TP) and the contrast ratio (CR). Mechanical properties were appraised with four-point bending strength (n=10), single edge V-notched beam (SEVNB) fracture toughness (n=8) and Vickers hardness (n=10). The aging stability was evaluated by measuring the tetragonal to monoclinic transformation (n=3) after accelerated hydrothermal aging in steam at 134 degrees C, and the transformation curves were fitted by the Mehl-Avrami-Johnson (MAJ) equation. Data were analyzed by one-way ANOVA, followed by Tukey's HSD test (alpha=0.05). RESULTS: Lowering the alumina content below 0.25wt.% avoided the formation of alumina particles and therefore increased the translucency of 3Y-TZP ceramics, but the hydrothermal aging stability was reduced. A higher yttria content (5mol%) introduced about 50% cubic zirconia phase and gave rise to the most translucent and aging-resistant Y-TZP ceramics, but the fracture toughness and strength were considerably sacrificed. 0.2mol% La2O3 doping of 3Y-TZP tailored the grain boundary chemistry and significantly improved the aging resistance and translucency. Although the translucency improvement by La2O3 doping was less effective than for introducing a substantial amount of cubic zirconia, this strategy was able to maintain the mechanical properties of typical 3Y-TZP ceramics. SIGNIFICANCE: Three different approaches were compared to improve the translucency of 3Y-TZP ceramics.
	Address	KU Leuven, Department of Materials Engineering, Kasteelpark Arenberg 44, Belgium
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Wos	000389516400003	Publication Date	2016-10-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0109-5641	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.07	Times cited		Open Access
	Notes	The authors acknowledge the Research Fund of KU Leu- ven under project 0T/10/052 and the Fund for Scientific Research Flanders (FWO-Vlaanderen) under grant G.0431.10N. F. Zhang thanks the Research Fund of KU Leuven for her post- doctoral fellowship (PDM/15/153). We thank M. Peumans for the translucency measurements.			Approved	Most recent IF: 4.07
	Call Number	EMAT @ emat @ c:irua:136821			Serial	4313
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	Author	Zhang, F.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Naert, I.; Van Meerbeek, B.; Vleugels, J.
	Title	Strength, toughness and aging stability of highly-translucent Y-TZP ceramics for dental restorations			Type	A1 Journal article
	Year	2016	Publication	Dental materials	Abbreviated Journal	Dent Mater
	Volume	32	Issue	12	Pages	E327-E337
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Objective. The aim was to evaluate the optical properties, mechanical properties and aging stability of yttria-stabilized zirconia with different compositions, highlighting the influence of the alumina addition, Y2O3 content and La2O3 doping on the translucency. Methods. Five different Y-TZP zirconia powders (3 commercially available and 2 experimentally modified) were sintered under the same conditions and characterized by X-ray diffraction with Rietveld analysis and scanning electron microscopy (SEM). Translucency (n = 6/group) was measured with a color meter, allowing to calculate the translucency parameter (TP) and the contrast ratio (CR). Mechanical properties were appraised with four-point bending strength (n = 10), single edge V-notched beam (SEVNB) fracture toughness (n = 8) and Vickers hardness (n = 10). The aging stability was evaluated by measuring the tetragonal to monoclinic transformation (n = 3) after accelerated hydrothermal aging in steam at 134 degrees C, and the transformation curves were fitted by the Mehl-Avrami-Johnson (MAJ) equation. Data were analyzed by one-way ANOVA, followed by Tukey's HSD test (alpha = 0.05). Results. Lowering the alumina content below 0.25 wt.% avoided the formation of alumina particles and therefore increased the translucency of 3Y-TZP ceramics, but the hydrothermal aging stability was reduced. A higher yttria content (5 mol%) introduced about 50% cubic zirconia phase and gave rise to the most translucent and aging-resistant Y-TZP ceramics, but the fracture toughness and strength were considerably sacrificed. 0.2 mol% La2O3 doping of 3Y-TZP tailored the grain boundary chemistry and significantly improved the aging resistance and translucency. Although the translucency improvement by La2O3 doping was less effective than for introducing a substantial amount of cubic zirconia, this strategy was able to maintain the mechanical properties of typical 3Y-TZP ceramics. Significance. Three different approaches were compared to improve the translucency of 3YTZP ceramics. (C) 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Copenhagen	Editor
	Language		Wos	000389516400003	Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0109-5641	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	4.07	Times cited	47	Open Access
	Notes				Approved	Most recent IF: 4.07
	Call Number	UA @ lucian @ c:irua:140246			Serial	4447
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	Author	Zhang, F.; Chevalier, J.; Olagnon, C.; Batuk, M.; Hadermann, J.; Van Meerbeek, B.; Vleugels, J.
	Title	Grain-boundary engineering for aging and slow-crack-growth resistant zirconia			Type	A1 Journal article
	Year	2017	Publication	Journal of dental research	Abbreviated Journal	J Dent Res
	Volume	96	Issue	7	Pages	774-779
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Ceramic materials are prone to slow crack growth, resulting in strength degradation over time. Although yttria-stabilized zirconia (Y-TZP) ceramics have higher crack resistance than other dental ceramics, their aging susceptibility threatens their long-term performance in aqueous environments such as the oral cavity. Unfortunately, increasing the aging resistance of Y-TZP ceramics normally reduces their crack resistance. Our recently conducted systematic study of doping 3Y-TZP with various trivalent cations revealed that lanthanum oxide (La2O3) and aluminum oxide (Al2O3) have the most potent effect to retard the aging kinetics of 3Y-TZP. In this study, the crack-propagation behavior of La2O3 and Al2O3 co-doped 3Y-TZP ceramics was investigated by double-torsion methods. The grain boundaries were examined using scanning transmission electron microscopy and energy-dispersive spectroscopy (STEM-EDS). Correlating these analytic data with hydrothermal aging studies using different doping systems, a strategy to strongly bind the segregated dopant cations with the oxygen vacancies at the zirconia-grain boundary was found to improve effectively the aging resistance of Y-TZP ceramics without affecting the resistance to crack propagation.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	St. Louis, Mo.	Editor
	Language		Wos	000403934500010	Publication Date	2017-03-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-0345	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.755	Times cited	3	Open Access	Not_Open_Access
	Notes	; This research was supported by the Research Fund of KU Leuven under project 0T/ 10/052 and the Research Foundation-Flanders (FWO-Vlaanderen) under grant G.0431.10N. We thank J.W. Seo for TEM and sample preparations. F. Zhang thanks the Research Fund of KU Leuven for her postdoctoral fellowship (PDM/15/153) and the JECS-Trust for the travel grant (No. 201599) to perform double-torsion testing in the MATEIS lab of INSA, Lyon, France. Jerome Chevalier would like to dedicate this paper to Maria Cattani Lorente, who recently passed away under tragic conditions. She was deeply involved in the study of dental zirconia and we will miss her. The authors declare no potential conflicts of interest with respect to the authorship and/or publication of this article. ;			Approved	Most recent IF: 4.755
	Call Number	UA @ lucian @ c:irua:144161			Serial	4660
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	Author	Zhang, F.; Batuk, M.; Hadermann, J.; Manfredi, G.; Mariën, A.; Vanmeensel, K.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J.
	Title	Effect of cation dopant radius on the hydrothermal stability of tetragonal zirconia: Grain boundary segregation and oxygen vacancy annihilation			Type	A1 Journal article
	Year	2016	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	106	Issue	106	Pages	48-58
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The hydrothermal aging stability of 3Y-TZP-xM2O3 (M = La, Nd, Sc) was investigated as a function of 0.02–5 mol% M2O3 dopant content and correlated to the overall phase content, t-ZrO2 lattice parameters, grain size distribution, grain boundary chemistry and ionic conductivity. The increased aging stability with increasing Sc2O3 content and the optimum content of 0.4–0.6 mol% Nd2O3 or 0.2–0.4 mol% La2O3, resulting in the highest aging resistance, could be directly related to the constituent phases and the lattice parameters of the remaining tetragonal zirconia. At low M2O3 dopant contents ≤0.4 mol%, the different aging behavior of tetragonal zirconia was attributed to the defect structure of the zirconia grain boundary which was influenced by the dopant cation radius. It was observed that the grain boundary ionic resistivity and the aging resistance followed the same trend: La3+ > Nd3+ > Al3+ > Sc3+, proving that hydrothermal aging is driven by the diffusion of water-derived mobile species through the oxygen vacancies. Accordingly, we elucidated the underlying mechanism by which a larger trivalent cation segregating at the zirconia grain boundary resulted in a higher aging resistance.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000371650300006	Publication Date	2016-01-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1359-6454	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.301	Times cited	37	Open Access
	Notes	The authors acknowledge the Research Fund of KU Leuven under project 0T/10/052 and the Fund for Scientific Research Flanders (FWO-Vlaanderen) under grant G.0431.10N. F. Zhang thanks the Research Fund of KU Leuven for her post-doctoral fellowship (PDM/15/153).			Approved	Most recent IF: 5.301
	Call Number	c:irua:132435			Serial	4076
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	Author	Zeng, Y.I.; Menghini, M.; Li, D.Y.; Lin, S.S.; Ye, Z.Z.; Hadermann, J.; Moorkens, T.; Seo, J.W.; Locquet, J.-P.; van Haesendonck, C.
	Title	Unexpected optical response of single ZnO nanowires probed using controllable electrical contacts			Type	A1 Journal article
	Year	2011	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	13	Issue	15	Pages	6931-6935
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Relying on combined electron-beam lithography and lift-off methods Au/Ti bilayer electrical contacts were attached to individual ZnO nanowires (NWs) that were grown by a vapor phase deposition method. Reliable Schottky-type as well as ohmic contacts were obtained depending on whether or not an ion milling process was used. The response of the ZnO NWs to ultraviolet light was found to be sensitive to the type of contacts. The intrinsic electronic properties of the ZnO NWs were studied in a field-effect transistor configuration. The transfer characteristics, including gate threshold voltage, hysteresis and operational mode, were demonstrated to unexpectedly respond to visible light. The origin of this effect could be accounted for by the presence of point defects in the ZnO NWs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000288951000019	Publication Date	2011-03-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1463-9076;1463-9084;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.123	Times cited	7	Open Access
	Notes				Approved	Most recent IF: 4.123; 2011 IF: 3.573
	Call Number	UA @ lucian @ c:irua:89378			Serial	3807
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	Author	Zeng, Y.-J.; Gauquelin, N.; Li, D.-Y.; Ruan, S.-C.; He, H.-P.; Egoavil, R.; Ye, Z.-Z.; Verbeeck, J.; Hadermann, J.; Van Bael, M.J.; Van Haesendonck, C.
	Title	Co-Rich ZnCoO Nanoparticles Embedded in Wurtzite Zn1-xCoxO Thin Films: Possible Origin of Superconductivity			Type	A1 Journal article
	Year	2015	Publication	ACS applied materials and interfaces	Abbreviated Journal	Acs Appl Mater Inter
	Volume	7	Issue	7	Pages	22166-22171
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Co-rich ZnCoO nanoparticles embedded in wurtzite Zn0.7Co0.3O thin films are grown by pulsed laser deposition on a Si substrate. Local superconductivity with an onset Tc at 5.9 K is demonstrated in the hybrid system. The unexpected superconductivity probably results from Co(3+) in the Co-rich ZnCoO nanoparticles or from the interface between the Co-rich nanoparticles and the Zn0.7Co0.3O matrix.
	Address	Solid State Physics and Magnetism Section, KU Leuven , Celestijnenlaan 200 D, BE-3001 Leuven, Belgium
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Wos	000363001500007	Publication Date	2015-09-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1944-8244;1944-8252;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	7.504	Times cited	13	Open Access
	Notes	This work has been supported by the Research Foundation − Flanders (FWO, Belgium) as well as by the Flemish Concerted Research Action program (BOF KU Leuven, GOA/14/007). N. G. and J. V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The Qu-Ant-EM microscope was partly funded by the Flemish Hercules Foundation. The work at Shenzhen University was supported by National Natural Science Foundation of China under Grant No. 61275144 and Natural Science Foundation of SZU. Y.-J. Z. acknowledges funding under grant No. SKL2015-12 from the State Key Laboratory of Silicon Materials; ECASJO_;			Approved	Most recent IF: 7.504; 2015 IF: 6.723
	Call Number	c:irua:129195 c:irua:129195UA @ admin @ c:irua:129195			Serial	3949
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	Author	Zelonka, K.; Sayer, M.; Freundorfer, A.P.; Hadermann, J.
	Title	Hydrothermal processing of barium strontium titanate sol-gel composite thin films			Type	A1 Journal article
	Year	2006	Publication	Journal of materials science	Abbreviated Journal	J Mater Sci
	Volume	41	Issue	12	Pages	3885-3897
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000239022100043	Publication Date	2006-04-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-2461;1573-4803;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.599	Times cited	10	Open Access
	Notes				Approved	Most recent IF: 2.599; 2006 IF: 0.999
	Call Number	UA @ lucian @ c:irua:60566			Serial	1539
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	Author	Zaghi, A.E.; Buffière, M.; Brammertz, G.; Batuk, M.; Lenaers, N.; Kniknie, B.; Hadermann, J.; Meuris, M.; Poortmans, J.; Vleugels, J.
	Title	Mechanical synthesis of high purity Cu-In-Se alloy nanopowder as precursor for printed CISe thin film solar cells			Type	A1 Journal article
	Year	2014	Publication	Advanced powder technology	Abbreviated Journal	Adv Powder Technol
	Volume	25	Issue	4	Pages	1254-1261
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Mechanical alloying and ball milling are low cost, up-scalable techniques for the preparation of high purity chalcogenide nanopowders to be used as precursor material for printing thin film solar cells. In this study, high purity copper indium selenium (Cu-In-Se) alloy nanopowders with 20-200 nm particle size were synthesized from macroscopic elemental Cu, In and Se powders via mechanical alloying and planetary ball milling. The particle size distribution, morphology, composition, and purity level of the synthesized Cu-In-Se alloy nanopowders were investigated. Thin Cu-In-Se alloy nanopowder ink coatings, deposited on Mo-coated glass substrates by doctor blading, were converted into a CuInSe2 semiconductor film by selenization heat treatment in Se vapor. The CuInSe2 film showed semiconducting band gap around 1 eV measured by photoluminescence spectroscopy. CuInSe2 absorber layer based thin film solar cell devices were fabricated to assess their performance. The solar cell device showed a total efficiency of 4.8%, as measured on 0.25 cm(2) area cell. (c) 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Zeist	Editor
	Language		Wos	000341871700015	Publication Date	2014-03-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0921-8831;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.659	Times cited	10	Open Access
	Notes				Approved	Most recent IF: 2.659; 2014 IF: 2.638
	Call Number	UA @ lucian @ c:irua:119896			Serial	1977
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	Author	Yang, T.; Perkisas, T.; Hadermann, J.; Croft, M.; Ignatov, A.; Van Tendeloo, G.; Greenblatt, M.
	Title	Synthesis and structure determination of ferromagnetic semiconductors LaAMnSnO₆(A = Sr, Ba)			Type	A1 Journal article
	Year	2011	Publication	Journal of materials chemistry	Abbreviated Journal	J Mater Chem
	Volume	21	Issue	1	Pages	199-205
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	LaAMnSnO(6) (A = Sr, Ba) have been synthesized by high temperature solid-state reactions under dynamic 1% H(2)/Ar flow. Rietveld refinements on room temperature powder X-ray diffraction data indicate that LaSrMnSnO(6) crystallizes in the GdFeO(3)-structure, with space group Pnma and, combined with transmission electron microscopy, LaBaMnSnO(6) in Imma. Both space groups are common in disordered double-perovskites. The Mn(3+) and Sn(4+) ions whose valence states were confirmed by X-ray absorption spectroscopy, are completely disordered over the B-sites and the BO(6) octahedra are slightly distorted. LaAMnSnO(6) are ferromagnetic semiconductors with a T(C) = 83 K for the Sr- and 66 K for the Ba-compound. The title compounds, together with the previously reported LaCaMnSnO(6) provide an interesting example of progression from Pnma to Imma as the tolerance factor increases. An analysis of the relationship between space group and tolerance factor for the series LaAMnMO(6) (A = Ca, Sr, Ba; M = Sn, Ru) provides a better understanding of the symmetry determination for double perovskites.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000285067300025	Publication Date	2010-10-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0959-9428;1364-5501;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	3	Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:95527			Serial	3440
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	Author	Yang, T.; Perkisas, T.; Hadermann, J.; Croft, M.; Ignatov, A.; Greenblatt, M.
	Title	B-site ordered perovskite LaSrMnNbO₆ : synthesis, structure and antiferromagnetism			Type	A1 Journal article
	Year	2010	Publication	Journal of solid state chemistry	Abbreviated Journal	J Solid State Chem
	Volume	183	Issue	11	Pages	2689-2694
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	LaSrMnNbO6 has been synthesized by high temperature solid state reaction under 1% H2/Ar dynamic flow. The structure is determined by Rietveld refinement of the powder X-ray diffraction data. It crystallizes in the monoclinic space group P21/n with the unit cell parameters: a=5.69187(12), b=5.74732(10), c=8.07018(15) Å and β=90.0504(29)°, which were also confirmed by electron diffraction. The Mn2+ and Nb5+ ions, whose valence states are confirmed by X-ray absorption near-edge spectroscopy, are almost completely ordered over the B-site (<1% inversion) of the perovskite structure due to the large differences of both cationic size (0.19 Å) and charge. The octahedral framework displays significant tilting distortion according to Glazers tilt system a−b−c+. Upon heating, LaSrMnNbO6 decomposes at 690 °C under O2 flow or at 775 °C in air. The magnetic susceptibility data indicate the presence of long-range antiferromagnetic ordering at TN=8 K; the experimentally observed effective paramagnetic moment, μeff=5.76 μB for high spin Mn2+ (3d5, S=5/2) is in good agreement with the calculated value (μcalcd=5.92 μB).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000284179800028	Publication Date	2010-09-13
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-4596;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.299	Times cited	13	Open Access
	Notes	Esteem 026019			Approved	Most recent IF: 2.299; 2010 IF: 2.261
	Call Number	UA @ lucian @ c:irua:85805			Serial	212
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	Author	Yang, T.; Abakumov, A.M.; Hadermann, J.; Van Tendeloo, G.; Nowik, I.; Stephens, P.W.; Hamberger, J.; Tsirlin, A.A.; Ramanujachary, K.V.; Lofland, S.; Croft, M.; Ignatov, A.; Sun, J.; Greenblatt, M.
	Title	_BiMnFe₂O₆, a polysynthetically twinned hcp MO structure			Type	A1 Journal article
	Year	2010	Publication	Chemical science	Abbreviated Journal	Chem Sci
	Volume	1	Issue	6	Pages	751-762
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The most efficient use of spatial volume and the lowest potential energies in the metal oxide structures are based on cubic close packing (ccp) or hexagonal close packing (hcp) of anions with cations occupying the interstices. A promising way to tune the composition of close packed oxides and design new compounds is related to fragmenting the parent structure into modules by periodically spaced planar interfaces, such as twin planes at the unit cell scale. The unique crystal chemistry properties of cations with a lone electron pair, such as Bi3+ or Pb2+, when located at interfaces, enables them to act as chemical scissors, to help relieve configurational strain. With this approach, we synthesized a new oxide, BiMnFe2O6, where fragments of the hypothetical hcp oxygen-based MO structure (the NiAs structure type), for the first time, serve as the building modules in a complex transition metal oxide. Mn3+ and Fe3+ ions are randomly distributed in two crystallographically independent sites (M1 and M2). The structure consists of quasi two-dimensional blocks of the 2H hexagonal close packed MO structure cut along the (114) crystal plane of the hcp lattice and stacked along the c axis. The blocks are related by a mirror operation that allows BiMnFe2O6 to be considered as a polysynthetically twinned 2H hcp MO structure. The transition to an AFM state with an incommensurate spin configuration at [similar] 212 K is established by 57Fe Mössbauer spectroscopy, magnetic susceptibility, specific heat and low temperature powder neutron diffraction.
	Address
	Corporate Author				Thesis
	Publisher	Royal Society of Chemistry	Place of Publication	Cambridge	Editor
	Language		Wos	000283939200013	Publication Date	2010-10-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2041-6520;2041-6539;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.668	Times cited	12	Open Access
	Notes				Approved	Most recent IF: 8.668; 2010 IF: NA
	Call Number	UA @ lucian @ c:irua:85823			Serial	3517
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	Author	Yang, C.; Batuk, M.; Jacquet, Q.; Rousse, G.; Yin, W.; Zhang, L.; Hadermann, J.; Abakumov, A.M.; Cibin, G.; Chadwick, A.; Tarascon, J.-M.; Grimaud, A.
	Title	Revealing pH-Dependent Activities and Surface Instabilities for Ni-Based Electrocatalysts during the Oxygen Evolution Reaction			Type	A1 Journal article
	Year	2018	Publication	ACS energy letters	Abbreviated Journal	Acs Energy Lett
	Volume		Issue		Pages	2884-2890
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Multiple electrochemical processes are involved at the catalyst/ electrolyte interface during the oxygen evolution reaction (OER). With the purpose of elucidating the complexity of surface dynamics upon OER, we systematically studied two Ni-based crystalline oxides (LaNiO3−δ and La2Li0.5Ni0.5O4) and compared them with the state-of-the-art Ni−Fe (oxy)- hydroxide amorphous catalyst. Electrochemical measurements such as rotating ring disk electrode (RRDE) and electrochemical quartz microbalance microscopy (EQCM) coupled with a series of physical characterizations including transmission electron microscopy (TEM) and X-ray absorption spectroscopy (XAS) were conducted to unravel the exact pH effect on both the OER activity and the catalyst stability. We demonstrate that for Ni-based crystalline catalysts the rate for surface degradation depends on the pH and is greater than the rate for surface reconstruction. This behavior is unlike that for the amorphous Ni oxyhydroxide catalyst, which is found to be more stable and pH-independent.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000453805100005	Publication Date	2018-11-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2380-8195	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access	Not_Open_Access: Available from 06.11.2019
	Notes	C.Y., J.-M.T., and A.G. acknowledge funding from the European Research Council (ERC) (FP/2014)/ERC GrantProject 670116-ARPEMA. A.G. acknowledges financial support from the ANR MIDWAY (Project ID ANR-17-CE05- 0008). We acknowledge Diamond Light Source for time awarded to the Energy Materials BAG on Beamline B18, under Proposal sp12559.			Approved	Most recent IF: NA
	Call Number	EMAT @ emat @c:irua:155046			Serial	5067
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	Author	Yan, L.; Niu, H.J.; Duong, G.V.; Suchomel, M.R.; Bacsa, J.; Chalker, P.R.; Hadermann, J.; Van Tendeloo, G.; Rosseinsky, M.J.
	Title	Cation ordering within the perovskite block of a six-layer Ruddlesden-Popper oxide from layer-by-layer growth artificial interfaces in complex unit cells			Type	A1 Journal article
	Year	2011	Publication	Chemical science	Abbreviated Journal	Chem Sci
	Volume	2	Issue	2	Pages	261-272
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The (AO)(ABO3)n Ruddlesden-Popper structure is an archetypal complex oxide consisting of two distinct structural units, an (AO) rock salt layer separating an n-octahedra thick perovskite block. Conventional high-temperature oxide synthesis methods cannot access members with n > 3, but low-temperature layer-by-layer thin film methods allow the preparation of materials with thicker perovskite blocks, exploiting high surface mobility and lattice matching with the substrate. This paper describes the growth of an n = 6 member CaO[(CSMO)2(LCMO)2 (CSMO)2] in which the six unit cell perovskite block is sub-divided into two central La0.67Ca0.33MnO3 (LCMO) and two terminal Ca0.85Sm0.15MnO3 (CSMO) layers to allow stabilization of the rock salt layer and variation of the transition metal charge.
	Address
	Corporate Author				Thesis
	Publisher	Royal Society of Chemistry	Place of Publication	Cambridge	Editor
	Language		Wos	000286327600010	Publication Date	2010-11-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2041-6520;2041-6539;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.668	Times cited	16	Open Access
	Notes				Approved	Most recent IF: 8.668; 2011 IF: 7.525
	Call Number	UA @ lucian @ c:irua:88652			Serial	300
Permanent link to this record



	Author	Yan, L.; Niu, H.; Bridges, C.A.; Marshall, P.A.; Hadermann, J.; Van Tendeloo, G.; Chalker, P.R.; Rosseinsky, M.J.
	Title	Unit-cell-level assembly of metastable transition-metal oxides by pulsed-laser deposition			Type	A1 Journal article
	Year	2007	Publication	Angewandte Chemie: international edition in English	Abbreviated Journal	Angew Chem Int Edit
	Volume	46	Issue	24	Pages	4539-4542
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Weinheim	Editor
	Language		Wos	000247500600026	Publication Date	2007-05-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1433-7851;1521-3773;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	11.994	Times cited	16	Open Access
	Notes				Approved	Most recent IF: 11.994; 2007 IF: 10.031
	Call Number	UA @ lucian @ c:irua:65593			Serial	3812
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	Author	Xu, X.; Jones, M.A.; Cassidy, S.J.; Manuel, P.; Orlandi, F.; Batuk, M.; Hadermann, J.; Clarke, S.J.
	Title	Magnetic Ordering in the Layered Cr(II) Oxide Arsenides Sr₂CrO₂Cr₂As₂and Ba₂CrO₂Cr₂As₂			Type	A1 Journal article
	Year	2020	Publication	Inorganic Chemistry	Abbreviated Journal	Inorg Chem
	Volume	59	Issue	21	Pages	15898-15912
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Sr2CrO2Cr2As2 and Ba2CrO2Cr2As2 with Cr2+ ions in CrO2 sheets and in CrAs layers crystallize with the Sr2Mn3Sb2O2 structure (space group I4/mmm, Z = 2) and lattice parameters a = 4.00800(2) Å, c = 18.8214(1) Å (Sr2CrO2Cr2As2) and a = 4.05506(2) Å, c = 20.5637(1) Å (Ba2CrO2Cr2As2) at room temperature. Powder neutron diffraction reveals checkerboard-type antiferromagnetic ordering of the Cr2+ ions in the arsenide layers below TN1Sr, of 600(10) K (Sr2CrO2Cr2As2) and TN1Ba 465(5) K (Ba2CrO2Cr2As2) with the moments initially directed perpendicular to the layers in both compounds. Checkerboard-type antiferromagnetic ordering of the Cr2+ ions in the oxide layer below 230(5) K for Ba2CrO2Cr2As2 occurs with these moments also perpendicular to the layers, consistent with the orientation preferences of d4 moments in the two layers. In contrast, below 330(5) K in Sr2CrO2Cr2As2, the oxide layer Cr2+ moments are initially oriented in the CrO2 plane; but on further cooling, these moments rotate to become perpendicular to the CrO2 planes, while the moments in the arsenide layers rotate by 90° with the moments on the two sublattices remaining orthogonal throughout [behavior recently reported independently by Liu et al. [Liu et al. Phys. Rev. B 2018, 98, 134416]]. In Sr2CrO2Cr2As2, electron diffraction and high resolution powder X-ray diffraction data show no evidence for a structural distortion that would allow the two Cr2+ sublattices to couple, but high resolution neutron powder diffraction data suggest a small incommensurability between the magnetic structure and the crystal structure, which may account for the coupling of the two sublattices and the observed spin reorientation. The saturation values of the Cr2+ moments in the CrO2 layers (3.34(1) μB (for Sr2CrO2Cr2As2) and 3.30(1) μB (for Ba2CrO2Cr2As2)) are larger than those in the CrAs layers (2.68(1) μB for Sr2CrO2Cr2As2 and 2.298(8) μB for Ba2CrO2Cr2As2) reflecting greater covalency in the arsenide layers.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000588738100035	Publication Date	2020-11-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0020-1669	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.6	Times cited		Open Access	OpenAccess
	Notes	We thank the UK EPSRC (EP/M020517/1 and EP/P018874/ 1) and the Leverhulme Trust (RPG-2014-221) for funding and the ISIS pulsed neutron and muon source (RB1610357 and RB1700075) and the Diamond Light Source Ltd. (EE13284 and EE18786) for the award of beam time. We thank Dr. A. Baker and Dr. C. Murray for support on I11.			Approved	Most recent IF: 4.6; 2020 IF: 4.857
	Call Number	EMAT @ emat @c:irua:176058			Serial	6704
Permanent link to this record



	Author	Watanabe, Y.; Hyeon-Deuk, K.; Yamamoto, T.; Yabuuchi, M.; Karakulina, O.M.; Noda, Y.; Kurihara, T.; Chang, I.-Y.; Higashi, M.; Tomita, O.; Tassel, C.; Kato, D.; Xia, J.; Goto, T.; Brown, C.M.; Shimoyama, Y.; Ogiwara, N.; Hadermann, J.; Abakumov, A.M.; Uchida, S.; Abe, R.; Kageyama, H.
	Title	Polyoxocationic antimony oxide cluster with acidic protons			Type	A1 Journal article
	Year	2022	Publication	Science Advances	Abbreviated Journal
	Volume	8	Issue	24	Pages	eabm5379-8
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The success and continued expansion of research on metal-oxo clusters owe largely to their structural richness and wide range of functions. However, while most of them known to date are negatively charged polyoxometalates, there is only a handful of cationic ones, much less functional ones. Here, we show an all-inorganic hydroxyiodide [H(10.)7Sb(32.1)O(44)][H2.1Sb2.1I8O6][Sb0.76I6](2)center dot 25H(2)O (HSbOI), forming a face-centered cubic structure with cationic Sb32O44 clusters and two types of anionic clusters in its interstitial spaces. Although it is submicrometer in size, electron diffraction tomography of HSbOI allowed the construction of the initial structural model, followed by powder Rietveld refinement to reach the final structure. The cationic cluster is characterized by the presence of acidic protons on its surface due to substantial Sb3+ deficiencies, which enables HSbOI to serve as an excellent solid acid catalyst. These results open up a frontier for the exploration and functionalization of cationic metal-oxo clusters containing heavy main group elements.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000812533800008	Publication Date	2022-06-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2375-2548	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	13.6	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 13.6
	Call Number	UA @ admin @ c:irua:189689			Serial	7091
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	Author	Volykhov, A.A.; Sanchez-Barriga, J.; Batuk, M.; Callaert, C.; Hadermann, J.; Sirotina, A.P.; Neudachina, V.S.; Belova, A.I.; Vladimirova, N.V.; Tamm, M.E.; Khmelevsky, N.O.; Escudero, C.; Perez-Dieste, V.; Knop-Gericke, A.; Yashina, L.V.
	Title	Can surface reactivity of mixed crystals be predicted from their counterparts? A case study of (Bi_1-xSb_x)₂Te₃ topological insulators			Type	A1 Journal article
	Year	2018	Publication	Journal of materials chemistry C : materials for optical and electronic devices	Abbreviated Journal	J Mater Chem C
	Volume	6	Issue	33	Pages	8941-8949
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The behavior of ternary mixed crystals or solid solutions and its correlation with the properties of their binary constituents is of fundamental interest. Due to their unique potential for application in future information technology, mixed crystals of topological insulators with the spin-locked, gapless states on their surfaces attract huge attention of physicists, chemists and material scientists. (Bi1-xSbx)(2)Te-3 solid solutions are among the best candidates for spintronic applications since the bulk carrier concentration can be tuned by varying x to obtain truly bulk-insulating samples, where the topological surface states largely contribute to the transport and the realization of the surface quantum Hall effect. As this ternary compound will be evidently used in the form of thin-film devices its chemical stability is an important practical issue. Based on the atomic resolution HAADF-TEM and EDX data together with the XPS results obtained both ex situ and in situ, we propose an atomistic picture of the mixed crystal reactivity compared to that of its binary constituents. We find that the surface reactivity is determined by the probability of oxygen attack on the Te-Sb bonds, which is directly proportional to the number of Te atoms bonded to at least one Sb atom. The oxidation mechanism includes formation of an amorphous antimony oxide at the very surface due to Sb diffusion from the first two quintuple layers, electron tunneling from the Fermi level of the crystal to oxygen, oxygen ion diffusion to the crystal, and finally, slow Te oxidation to the +4 oxidation state. The oxide layer thickness is limited by the electron transport, and the overall process resembles the Cabrera-Mott mechanism in metals. These observations are critical not only for current understanding of the chemical reactivity of complex crystals, but also to improve the performance of future spintronic devices based on topological materials.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000443279300007	Publication Date	2018-07-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2050-7526; 2050-7534	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	5.256	Times cited	3	Open Access	Not_Open_Access
	Notes	; The authors acknowledge financial support within the bilateral program "Russian-German Laboratory at BESSY II''. We thank Helmholtz-Zentrum Berlin for granting access to the beamlines RGBL, UE112-PGM2a and ISISS. Support of ALBA staff during measurements at the CIRCE beamline is gratefully acknowledged. We thank Dr Ivan Bobrikov for support in the XRD measurements and Daria Tsukanova for the participation in crystal preparation and XPS measurements. A. Volykhov thanks RSF (grant 18-73-00248) for financial support. A. I. Belova acknowledges support from the G-RISC Centre of Excellence. The work was supported by Helmholtz Gemeinschaft (Grant No. HRJRG-408) and RFBR (grant 14-03-31518). J. H. and C. C. acknowledge support from the University of Antwerp through the BOF grant 31445. ;			Approved	Most recent IF: 5.256
	Call Number	UA @ lucian @ c:irua:153647			Serial	5080
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	Author	Volykhov, A.A.; Frolov, A.S.; Neudachina, V.S.; Vladimirova, N.V.; Gerber, E.; Callaert, C.; Hadermann, J.; Khmelevsky, N.O.; Knop-Gericke, A.; Sanchez-Barriga, J.; Yashina, L.V.
	Title	Impact of ordering on the reactivity of mixed crystals of topological insulators with anion substitution: Bi₂SeTe₂ and Sb₂SeTe₂			Type	A1 Journal article
	Year	2021	Publication	Applied Surface Science	Abbreviated Journal	Appl Surf Sci
	Volume	541	Issue		Pages	148490
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Three-dimensional topological insulators are exotic materials with unique properties. Tetradymite type binary chalcogenides of bismuth and antimony, as well as their mixed crystals, belong to prototypical TIs. Potential device applications of these materials require in-depth knowledge of their stability in the ambient atmosphere and other media maintained during their processing. Here we investigated the reactivity of mixed crystals with anion substitution, Bi-2(Se1-xTex)(3) and Sb2(Se1-xTex)(3), towards molecular oxygen using both in situ and ex situ X-ray photoelectron spectroscopy. The results indicate that, in contrast to cation substitution, partial substitution of tellurium by selenium atoms leads to anomalously high surface reactivity, which even exceeds that of the most reactive binary constituent. We attribute this effect to anion ordering that essentially modifies the bond geometry, especially the respective bond angles as modeled by DFT.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000608492900003	Publication Date	2020-11-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0169-4332	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.387	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 3.387
	Call Number	UA @ admin @ c:irua:176067			Serial	6728
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	Author	Vladimirova, S.A.; Rumyantseva, M.N.; Filatova, D.G.; Chizhov, A.S.; Khmelevsky, N.O.; Konstantinova, E.A.; Kozlovsky, V.F.; Marchevsky, A.V.; Karakulina, O.M.; Hadermann, J.; Gaskov, A.M.
	Title	Cobalt location in p -CoO x / n -SnO 2 nanocomposites: Correlation with gas sensor performances			Type	A1 Journal Article
	Year	2017	Publication	Journal Of Alloys And Compounds	Abbreviated Journal	J Alloy Compd
	Volume	721	Issue		Pages	249-260
	Keywords	A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
	Abstract	Nanocomposites CoOx/SnO2 based on tin oxide powders with different crystallinity have been prepared by wet chemical synthesis and characterized in detail by ICP-MS, XPS, EPR, XRD, HAADF-STEM imaging and EDX-STEM mapping. It was shown that cobalt is distributed differently between the bulk and surface of SnO2 nanocrystals, which depends on the crystallinity of the SnO2 matrix. The measurements of gas sensor properties have been carried out during exposure to CO (10 ppm), and H2S (2 ppm) in dry air. The decrease of sensor signal toward CO was attributed to high catalytic activity of Co3O4 leading to oxidation of carbon monoxide entirely on the surface of catalyst particles. The formation of a p-CoOx/n-SnO2 heterojunction results in high sensitivity of nanocomposites in H2S detection. The conductance significantly changed in the presence of H2S, which was attributed to the formation of metallic cobalt sulfide and removal of the p – n junction.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000405252400030	Publication Date	2017-06-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0925-8388	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.133	Times cited		Open Access	Not_Open_Access
	Notes	This work was supported by ERA-Net.Plus grant N 096 FONSENS. EPR experiments were performed using the facilities of the Collective Use Center at the Moscow State University.			Approved	Most recent IF: 3.133
	Call Number	EMAT @ emat @			Serial	4711
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	Author	Vladimirova, S.A.; Rumyantseva, M.N.; Filatova, D.G.; Chizhov, A.S.; Khmelevsky, N.O.; Konstantinova, E.A.; Kozlovsky, V.F.; Marchevsky, A.V.; Karakulina, O.M.; Hadermann, J.; Gaskov, A.M.
	Title	Cobalt location in p-CoO_xIn-SnO₂ nanocomposites : correlation with gas sensor performances			Type	A1 Journal article
	Year	2017	Publication	Journal of alloys and compounds	Abbreviated Journal	J Alloy Compd
	Volume	721	Issue		Pages	249-260
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Nanocomposites CoOx/SnO2 based on tin oxide powders with different crystallinity have been prepared by wet chemical synthesis and characterized in detail by ICP-MS, XPS, EPR, XRD, HAADF-STEM imaging and EDX-STEM mapping. It was shown that cobalt is distributed differently between the bulk and surface of SnO2 nanocrystals, which depends on the crystallinity of the SnO2 matrix. The measurements of gas sensor properties have been carried out during exposure to CO (10 ppm), and H2S (2 ppm) in dry air. The decrease of sensor signal toward CO was attributed to high catalytic activity of Co3O4 leading to oxidation of carbon monoxide entirely on the surface of catalyst particles. The formation of a p-CoOx/n-SnO2 heterojunction results in high sensitivity of nanocomposites in H2S detection. The conductance significantly changed in the presence of H2S, which was attributed to the formation of metallic cobalt sulfide and removal of the p – n junction. (C) 2017 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0925-8388	ISBN		Additional Links	UA library record; ; WoS full record; WoS citing articles
	Impact Factor	3.133	Times cited		Open Access	Not_Open_Access: Available from 10.10.2019
	Notes	; This work was supported by ERA-Net.Plus grant N 096 FON-SENS. EPR experiments were performed using the facilities of the Collective Use Center at the Moscow State University. ;			Approved	Most recent IF: 3.133
	Call Number	UA @ lucian @ c:irua:145142			Serial	4714
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	Author	Vladimirova, N.V.; Frolov, A.S.; Sanchez-Barriga, J.; Clark, O.J.; Matsui, F.; Usachov, D.Y.; Muntwiler, M.; Callaert, C.; Hadermann, J.; Neudachina, V.S.; Tamm, M.E.; Yashina, L.V.
	Title	Occupancy of lattice positions probed by X-ray photoelectron diffraction : a case study of tetradymite topological insulators			Type	A1 Journal article
	Year	2023	Publication	Surfaces and interfaces	Abbreviated Journal
	Volume	36	Issue		Pages	102516-10
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Occupancy of different structural positions in a crystal lattice often seems to play a key role in material prop-erties. Several experimental techniques have been developed to uncover this issue, all of them being mostly bulk sensitive. However, many materials including topological insulators (TIs), which are among the most intriguing modern materials, are intended to be used in devices as thin films, for which the sublattice occupancy may differ from the bulk. One of the possible approaches to occupancy analysis is X-ray Photoelectron Diffraction (XPD), a structural method in surface science with chemical sensitivity. We applied this method in a case study of Sb2(Te1-xSex)3 mixed crystals, which belong to prototypical TIs. We used high-angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) as a reference method to verify our analysis. We revealed that the XPD data for vacuum cleaved bulk crystals are in excellent agreement with the reference ones. Also, we demonstrate that the anion occupancy near a naturally formed surface can be rather different from that of the bulk. The present results are relevant for a wide range of compositions where the system remains a topological phase, as we ultimately show by probing the transiently occupied topological surface state above the Fermi level by ultrafast photoemission.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000901694900001	Publication Date	2022-11-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2468-0230	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	6.2	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 6.2; 2023 IF: NA
	Call Number	UA @ admin @ c:irua:193502			Serial	7327
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	Author	Vishwakarma, M.; Varandani, D.; Hendrickx, M.; Hadermann, J.; Mehta, B.R.
	Title	Nanoscale photovoltage mapping in CZTSe/CuxSe heterostructure by using kelvin probe force microscopy			Type	A1 Journal article
	Year	2020	Publication	Materials Research Express	Abbreviated Journal
	Volume	7	Issue	1	Pages	016418
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	In the present work, kelvin probe force microscopy (KPFM) technique has been used to study the CZTSe/CuxSe bilayer interface prepared by multi-step deposition and selenization process of metal precursors. Transmission electron microscopy (TEM) confirmed the bilayer configuration of the CZTSe/CuxSe sample. Two configuration modes (surface mode and junction mode) in KPFM have been employed in order to measure the junction voltage under illumination conditions. The results show that CZTSe/CuxSe has small junction voltage of similar to 21 mV and the presence of CuxSe secondary phase in the CZTSe grain boundaries changes the workfunction of the local grain boundaries region. The negligible photovoltage difference between grain and grain boundaries in photovoltage image indicates that CuxSe phase deteriorates the higher photovoltage at grain boundaries normally observed in CZTSe based device. These results can be important for understanding the role of secondary phases in CZTSe based junction devices.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000520120900001	Publication Date	2019-12-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access	OpenAccess
	Notes	; Authors acknowledges support provided DST in the forms of InSOL and Indo-Swiss projects. We also acknowledge Joke Hadermann EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Belgium for helping in TEM measurements. M V Manoj Vishwakarma acknowledges IIT Delhi for MHRD fellowship. Prof B R Mehta acknowledges the support of the Schlumberger chair professorship. M V also acknowledges the support of DST-FIST Raman facility. ;			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:167843			Serial	6567
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	Author	Vishwakarma, M.; Thota, N.; Karakulina, O.; Hadermann, J.; Mehta, B.R.
	Title	Role of graphene inter layer on the formation of the MoS₂ – CZTS interface during growth			Type	P1 Proceeding
	Year	2018	Publication	(icc-2017)	Abbreviated Journal
	Volume		Issue		Pages
	Keywords	P1 Proceeding; Electron microscopy for materials research (EMAT)
	Abstract	The growth of MoS2 layer near the Mo/CZTS interface during sulphurization process can have an impact on back contact cell parameters (series resistance and fill factor) depending upon the thickness or quality of MoS2. This study reports the dependence of the thickness of interfacial MoS2 layer on the growth of graphene at the interface between molybdenum back contact and deposited CZTS layer. The graphene layer reduces the accumulation of Zn/ZnS, Sn/SnO2 and formation of pores near the MoS2-CZTS interface. The use of graphene as interface layer can be potentially useful for improving the quality of Mo/MoS2/CZTS interface.
	Address
	Corporate Author				Thesis
	Publisher	Amer inst physics	Place of Publication	Melville	Editor
	Language		Wos	000436313003046	Publication Date	2018-05-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	1953	Series Issue		Edition
	ISSN	978-0-7354-1648-2; 0094-243x; 0094-243x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	1	Open Access	OpenAccess
	Notes	; The authors acknowledge support provided by DST project. M.V. acknowledges IIT Delhi for MHRD fellowship. Prof. B. R. Mehta acknowledges the support of the Schlumberger chair professorship. ;			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:153203			Serial	5126
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	Author	Vishwakarma, M.; Kumar, M.; Hendrickx, M.; Hadermann, J.; Singh, A.P.; Batra, Y.; Mehta, B.R.
	Title	Enhancing the hydrogen evolution properties of kesterite absorber by Si-doping in the surface of CZTS thin film			Type	A1 Journal article
	Year	2021	Publication	Advanced Materials Interfaces	Abbreviated Journal	Adv Mater Interfaces
	Volume		Issue		Pages	2002124
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	In this work, the effects of Si-doping in Cu2ZnSnS4 are examined computationally and experimentally. The density functional theory calculations show that an increasing concentration of Si (from x = 0 to x = 1) yields a band gap rise due to shifting of the conduction band minimum towards higher energy states in the Cu2Zn(Sn1-xSix)S-4. CZTSiS thin film prepared by co-sputtering process shows Cu2Zn(Sn1-xSix)S-4 (Si-rich) and Cu2ZnSnS4 (S-rich) kesterite phases on the surface and in the bulk of the sample, respectively. A significant change in surface electronic properties is observed in CZTSiS thin film. Si-doping in CZTS inverts the band bending at grain-boundaries from downward to upward and the Fermi level of CZTSiS shifts upward. Further, the coating of the CdS and ZnO layer improves the photocurrent to approximate to 5.57 mA cm(-2) at -0.41 V-RHE in the CZTSiS/CdS/ZnO sample, which is 2.39 times higher than that of pure CZTS. The flat band potential increases from CZTS approximate to 0.43 V-RHE to CZTSiS/CdS/ZnO approximate to 1.31 V-RHE indicating the faster carrier separation process at the electrode-electrolyte interface in the latter sample. CdS/ZnO layers over CZTSiS significantly reduce the charge transfer resistance at the semiconductor-electrolyte interface.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000635804900001	Publication Date	2021-04-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2196-7350	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.279	Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 4.279
	Call Number	UA @ admin @ c:irua:177688			Serial	6780
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	Author	Vishwakarma, M.; Karakulina, O.M.; Abakumov, A.M.; Hadermann, J.; Mehta, B.R.
	Title	Nanoscale Characterization of Growth of Secondary Phases in Off-Stoichiometric CZTS Thin Films			Type	A1 Journal article
	Year	2018	Publication	Journal of nanoscience and nanotechnology	Abbreviated Journal	J Nanosci Nanotechno
	Volume	18	Issue	3	Pages	1688-1695
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The presence of secondary phases is one of the main issues that hinder the growth of pure kesterite Cu2ZnSnS4 (CZTS) based thin films with suitable electronic and junction properties for efficient solar cell devices. In this work, CZTS thin films with varied Zn and Sn content have been prepared by RF-power controlled co-sputtering deposition using Cu, ZnS and SnS targets and a subsequent sulphurization step. Detailed TEM investigations show that the film shows a layered structure with the majority of the top layer being the kesterite phase. Depending on the initial thin film composition, either about ~1 μm Cu-rich and Zn-poor kesterite or stoichiometric CZTS is formed as top layer. X-ray diffraction, Raman spectroscopy and transmission electron microscopy reveal the presence of Cu2−x S, ZnS and SnO2 minor secondary phases in the form of nanoinclusions or nanoparticles or intermediate layers.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000426033400022	Publication Date	2018-03-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1533-4880	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.483	Times cited		Open Access	Not_Open_Access
	Notes	Manoj Vishwakarma acknowl- edges IIT Delhi for MHRD fellowship. Professor B. R. Mehta acknowledges the support of the Schlumberger chair professorship. Manoj Vishwakarma, Joke Hadermann and Olesia M. karakulina acknowledge support provided by InsoL-DST. Manoj Vishwakarma acknowledges sup- port provided by CSIR funded projects and the support of DST-FIST Raman facility. References			Approved	Most recent IF: 1.483
	Call Number	EMAT @ emat @c:irua:147505			Serial	4775
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	Author	Vishwakarma, M.; Batra, Y.; Hadermann, J.; Singh, A.; Ghosh, A.; Mehta, B.R.
	Title	Exploring the role of graphene oxide as a co-catalyst in the CZTS photocathodes for improved photoelectrochemical properties			Type	A1 Journal article
	Year	2022	Publication	ACS applied energy materials	Abbreviated Journal
	Volume	5	Issue	6	Pages	7538-7549
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	The hydrogen evolution properties of CZTS heterostructure photocathodes are reported with graphene oxide (GO) as a co-catalyst layer coated by a drop-cast method and an Al2O3 protection layer fabricated using atomic layer deposition. In the CZTS absorber, a minor deviation from stoichiometry across the cross section of the thin film results in nanoscale growth of spurious phases, but the kesterite phase remains the dominant phase. We have investigated the band alignment parameters such as the band gap, work function, and Fermi level position that are crucial for making kesterite-based heterostructure devices. The photocurrent density in the photocathode CZTS/CdS/ZnO is found to be improved to -4.71 mAmiddotcm(-2) at -0.40 V-RHE, which is 3 times that of the pure CZTS. This enhanced photoresponse can be attributed to faster carrier separation at p-n junction regions driven by upward band bending at CZTS grain boundaries and the ZnO layer. GO as a co-catalyst over the heterostructure photocathode significantly improves the photocurrent density to -6.14 mAmiddotcm(-2) at -0.40 V-RHE by effective charge migration in the CZTS/CdS/ZnO/GO configuration, but the onset potential shifts only after application of the Al2O3 protection layer. Significant photocurrents of -29 mAmiddotcm(-2) at -0.40 V-RHE and -8 mAmiddotcm(-2) at 0 V-RHE are observed, with an onset potential of 0.7 V-RHE in CZTS/CdS/ZnO/GO/Al2O3. The heterostructure configuration and the GO co-catalyst reduce the charge-transfer resistance, while the Al2O3 top layer provides a stable photocurrent for a prolonged time (similar to 16 h). The GO co-catalyst increases the flat band potential from 0.26 to 0.46 V-RHE in CZTS/CdS/ZnO/GO, which supports the bias-induced band bending at the electrolyte-electrode interface.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000820418400001	Publication Date	2022-05-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2574-0962	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.4	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 6.4
	Call Number	UA @ admin @ c:irua:189666			Serial	7082
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