Article
Chemistry, Physical
Jia Song, Shaochen Zhu, De Ning, Henny J. M. Bouwmeester
Summary: The structural evolution, electrical conductivity, oxygen nonstoichiometry, and oxygen transport properties of La1-xCaxFeO3-δ perovskite-type oxides were investigated. The results showed that Ca doping is mainly compensated by formation of electron holes rather than by oxygen vacancies, and oxygen vacancy diffusion coefficient and ionic conductivity increase with increasing Ca content in the compositions. The effective migration barrier for oxygen diffusion decreases with decreasing oxygen vacancy formation enthalpy.
JOURNAL OF MATERIALS CHEMISTRY A
(2021)
Article
Chemistry, Physical
Jane Banner, Emily Ghosh, Srikanth Gopalan
Summary: The role of porosity in equilibration kinetics in electrical conductivity relaxation (ECR) experiments is highlighted in this study. The use of porous conductivity bars allows for quicker experiments and is critical for determining oxygen exchange kinetics. Both porous and dense bars show similar trends with oxygen partial pressure and differences between oxidation and reduction transients.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Elisabeth Robens, Robert Rauschen, Johannes Kaub, Jana P. Parras, Dennis Kemp, Colin L. Freeman, Roger A. De Souza
Summary: In this study, molecular dynamics simulations were used to calculate oxygen diffusion coefficients in CaTiO3 with different crystal structures, revealing higher activation enthalpy for oxygen diffusion in the orthorhombic structure compared to the cubic structure. The presence of acceptor-type cation defects was found to negatively impact oxygen diffusion, especially in low-symmetry structures. The results provide insights into experimental transport studies, trends for alkaline-earth perovskites, and highlight the advantages of using MD simulations for studying ion migration in distorted perovskite structures.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Engineering, Environmental
S. A. Chizhik, M. P. Popov, I. Kovalev, S. F. Bychkov, A. P. Nemudry
Summary: The kinetic parameters of a reaction between a nonstoichiometric oxide and molecular oxygen were determined using two independent methods, steady-state oxygen permeability and transient kinetics. Mathematical models were used to analyze the results, taking into account the inhomogeneity of conditions and gas flows. The results showed a quantitative agreement between the two methods, considering the dependence of the reaction rate constant on oxide stoichiometry.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Sen Lian, Lei He, Congcong Li, Junfeng Ren, Lei Bi, Meina Chen, Zijing Lin
Summary: The perovskite/Ruddlesden-Popper oxide heterostructure (Nd,Sr)CoO3 (NSC113)/(Nd,Sr)2CoO4 (NSC214) has been found to significantly enhance the oxygen reduction reaction (ORR) activity due to two main factors: enhanced oxygen adsorption and accelerated transport of interstitial oxygen. Additionally, the perovskite/double-layered R-P oxide heterostructure is predicted to exhibit better ORR performance compared to the perovskite/single-layered R-P oxide heterostructure. This work provides important insights into the atomic-level mechanism of ORR enhancement on perovskite/R-P oxide heterostructures, which is highly significant for the development of high-performance electrochemical devices.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Materials Science, Ceramics
Yunpeng Zheng, Mingchu Zou, Wenyu Zhang, Di Yi, Jinle Lan, Ce-Wen Nan, Yuan-Hua Lin
Summary: High-entropy strategy and defect engineering were used to significantly suppress thermal conductivity and optimize electrical conductivity in SrTiO3-based thermoelectric ceramics. The minimum thermal conductivity in high-entropy TiO3 bulks can be reduced to 1.17 W/(m • K), with a power factor of 295μW/(m • K-2), and a ZT value of 0.2 at 873K.
JOURNAL OF ADVANCED CERAMICS
(2021)
Article
Engineering, Environmental
Mikhail P. Popov, Marko I. Gongola, Ivan Kovalev, Rostislav D. Guskov, Stanislav A. Chizhik, Alexander P. Nemudry
Summary: The transient kinetics of reequilibration in the reaction of nonstoichiometric oxide Ba0.5Sr0.5Co0.75Fe0.2Mo0.05O3-delta with oxygen was studied using the oxygen partial pressure relaxation technique. The study revealed a change in the mechanism of the rate-determining step of the reaction at the phase transition point.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Hai-Long Sun, Chuan-Lu Yang, Mei-Shan Wang, Xiao-Guang Ma, You-Gen Yi
Summary: Two high dimensionless figure of merit (ZT) materials and high energy conversion efficiency (η) thermoelectric materials AgMF3 (M = Zn, Cd) are proposed based on first-principles calculations, demonstrating promising thermoelectric performance. The theoretical findings provide valuable insights for the development of efficient thermoelectric materials.
MATERIALS TODAY ENERGY
(2021)
Article
Chemistry, Physical
Yong Youn, Basharat Hussain, Abid Ullah, In Jun Hwang, Jiweon Shin, Jong-Eun Hong, Dong Woo Joh, Seung-Bok Lee, Rak-Hyun Song, Seok-Joo Park, Tae Woo Kim, Yoonseok Choi, Tak-Hyoung Lim, Hye-Sung Kim
Summary: Hexagonal perovskite-related oxides have attracted significant attention for their potential applications in electrochemical devices. This study reveals the anisotropic characteristics of proton conduction behavior in a Ba5Er2Al2ZrO13 (BEAZ) hexagonal perovskite electrolyte-supported cell. By controlling the orientation of the grains in the BEAZ thin film, the researchers demonstrate that proton migration is more favorable in the lateral direction than in the vertical direction. Density functional theory calculations and ab initio molecular dynamics simulations suggest that anisotropic proton migration is preferred through the perovskite-like layer.
CHEMISTRY OF MATERIALS
(2023)
Article
Materials Science, Ceramics
Zuoan Li, Reidar Haugsrud
Summary: This study investigates the effect of temperature and oxygen partial pressure on conductivity relaxation in uncoated and coated La2Ni0.5Cu0.5O4+delta membranes. The results show that surface kinetics significantly influence the relaxation profiles, particularly at low temperatures.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Chung Hyeon Jang, Ye In Kim, Amit Kumar Harit, Jung Min Ha, Sejeong Park, Young Wook Noh, Ah-young Lee, Kyeong Su Kim, Jae Woong Jung, Han Young Woo, Myoung Hoon Song
Summary: This study reports highly efficient green-emitting PeLEDs by introducing semiconducting molecular additives (Fl-OEGA and Fl-C8A). The conjugated additives exist primarily at the grain boundaries of perovskite, reducing the contact potential difference and residual tensile stress. The PeLEDs with Fl-OEGA show minimal shift in turn-on voltage and less decrease in current density compared to devices with insulating EDEA. Furthermore, the 3D CsPbBr3-PeLEDs achieve the highest external quantum efficiency of 21.3% with the incorporation of semiconducting Fl-OEGA as a new multifunctional additive.
ADVANCED MATERIALS
(2023)
Article
Engineering, Chemical
Ni Yan, Rahul Sujanani, Jovan Kamcev, Eui-Soung Jang, Kentaro Kobayashi, Donald R. Paul, Benny D. Freeman
Summary: Salt permeability and ionic conductivity are critical properties for membranes in water purification and energy applications. In this study, a series of uncharged and charged membranes were synthesized and the effects of polymer structure on ion transport properties were investigated. The results showed that water content has a strong influence on ion diffusion in both uncharged and charged polymers.
JOURNAL OF MEMBRANE SCIENCE
(2022)
Article
Chemistry, Physical
Yuan Feng, Hanyu Jin, Shuai Wang
Summary: The difference in oxygen vacancy formation energy and oxygen migration barrier between the surface and the bulk in LaFeO3 perovskite was investigated via DFT. The effect of Sr doping was considered. The results showed that Sr doping enhanced the covalency of the interaction between Fe and O, leading to a lower oxygen vacancy formation energy and a smaller oxygen migration barrier.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Physics, Fluids & Plasmas
Michael A. Klatt, Robert M. Ziff, Salvatore Torquato
Summary: Transport properties of porous media are closely related to their pore-space microstructures, with the critical pore radius 8c and the second moment of the pore size (82) serving as key length scales. The alternative estimate of fluid permeability based on (82) is promising for porous media with a well-connected pore space. Models with effectively hyperuniformity tend to exhibit lower fluid permeability values compared to nonhyperuniform counterparts.
Article
Engineering, Environmental
S. A. Chizhik, I. V. Kovalev, M. P. Popov, S. F. Bychkov, A. P. Nemudry
Summary: This study investigates the relationship between the properties of perovskite related oxides and the oxygen stoichiometry. It proposes a continuous homologous series approach and utilizes new methods to study the equilibrium and kinetic properties of SrFe(0.98)8Mo(0.02)O(3-delta). The power law dependence of the kinetic parameters on the equilibrium oxygen partial pressure is considered as a result of a linear free energy relationship.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Nina Schroedl, Edith Bucher, Christian Gspan, Andreas Egger, Christian Ganser, Christian Teichert, Ferdinand Hofer, Werner Sitte
SOLID STATE IONICS
(2016)
Article
Chemistry, Physical
Martin Perz, Edith Bucher, Christian Gspan, Joerg Waldhausl, Ferdinand Hofer, Werner Sitte
SOLID STATE IONICS
(2016)
Article
Electrochemistry
Christian Berger, Edith Bucher, Christian Gspan, Alexander Menzel, Werner Sitte
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2017)
Article
Chemistry, Physical
Christian Berger, Edith Bucher, Werner Sitte
SOLID STATE IONICS
(2017)
Article
Chemistry, Physical
E. Bucher, C. Gspan, T. Hoeschen, F. Hofer, W. Sitte
SOLID STATE IONICS
(2017)
Article
Chemistry, Inorganic & Nuclear
Christian Berger, Edith Bucher, Andreas Windischbacher, A. Daniel Boese, Werner Sitte
JOURNAL OF SOLID STATE CHEMISTRY
(2018)
Article
Chemistry, Physical
Christian Berger, Edith Bucher, Christian Gspan, Alexander Menzel, Werner Sitte
SOLID STATE IONICS
(2018)
Article
Materials Science, Multidisciplinary
Gregor Mori, Karl J. Vidic, Edith Bucher, Muhammad Yasir, Daniel Hornauer, Manfred Nachtnebel, Harald Fitzek, Hartmuth Schroettner
MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION
(2019)
Article
Chemistry, Physical
Vanja Subotic, Thomas Thaller, Benjamin Koenigshofer, Norbert H. Menzler, Edith Bucher, Andreas Egger, Christoph Hochenauer
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2020)
Article
Materials Science, Multidisciplinary
Christian Berger, Edith Bucher, Judith Lammer, Christina Nader, Werner Sitte
Summary: Compounds in the series La0.8-xNdxCa0.2FeO3-delta (0.1 <= x <= 0.7) were synthesized via a sol-gel route. The materials were found to crystallize as single-phase orthorhombic perovskites for x values between 0 and 0.6, with Nd substitution impacting the unit cell volume and thermal expansion behavior. Additionally, the transition from orthorhombic to trigonal modification observed in La0.8Ca0.2FeO3-delta was suppressed in Nd-substituted compounds.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Chemistry, Physical
Christian Berger, Edith Bucher, Rotraut Merkle, Christina Nader, Judith Lammer, Werner Grogger, Joachim Maier, Werner Sitte
Summary: Self-generated composites of BaCe1-(x+z)FexYzO3-delta series were synthesized by one-pot method, consisting of proton and electron conducting phases, suitable for electrode materials in protonic ceramic fuel cells and electrolyzers. X-ray diffraction and scanning electron microscopy revealed the presence of Fe-rich phases and Ce-rich perovskite phases, with Y substitution influencing mutual solubility. Additional strategies to enhance proton uptake by substituting ions with different basicity are discussed.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Materials Science, Multidisciplinary
Manuela Nimmervoll, Gregor Mori, Edith Bucher, Alexander Schmid, Roland Haubner
Summary: This study investigates the high-temperature corrosion behavior of N10276 steel in an atmosphere containing H2S and HCl, explaining the corrosion behavior at 480°C and 680°C by considering the impact of main alloying elements, thermodynamic considerations, and kinetic effects. The corrosion behavior of N10276 is compared with previously tested Fe-Cr-Ni alloys, revealing differences in their behavior in the same corrosive atmosphere.
Article
Microscopy
Judith Lammer, Christian Berger, Stefan Loeffler, Daniel Knez, Paolo Longo, Gerald Kothleitner, Ferdinand Hofer, Georg Haberfehlner, Edith Bucher, Werner Sitte, Werner Grogger
Summary: In this work, a procedure to determine the concentration of two elements within atomic columns from EELS elemental maps was presented and successfully applied to Ba1.1La1.9Fe2O7.
Article
Materials Science, Multidisciplinary
Manuela Nimmervoll, Gregor Mori, Edith Bucher, Stefan Honig, Roland Haubner
Summary: This paper presents a detailed analysis of high-temperature corrosion mechanisms in reducing atmospheres containing HCl and H2S. The analysis is based on experimental observations and thermodynamic calculations. It also explains the corrosion behavior of a specific alloy and provides correlations between thermodynamic calculations and practical findings.
MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION
(2022)
Article
Chemistry, Physical
Sarah Eisbacher-Lubensky, Andreas Egger, Werner Sitte, Edith Bucher
Summary: The rare earth nickelate La2Ni0.9Co0.1O4+delta (LNCO) was synthesized via the citrate/EDTA method, and it was confirmed to have a single-phase structure. The substitution of nickel with cobalt in LNCO led to higher values of the surface exchange coefficient and slightly reduced electronic conductivity. The oxygen non-stoichiometry of LNCO was studied, and its thermal expansion coefficients were found to be similar to common solid electrolytes. LNCO shows potential as an air electrode in solid oxide cells.
SOLID STATE IONICS
(2023)
