Article
Materials Science, Multidisciplinary
Cintia Hartmann, Jerome Laurencin, Gregory Geneste
Summary: The stability, trapping and mobility of electron holes in lanthanum ferrite (LaFeO3) and lan-thanum-strontium ferrite (La1-xSrxFeO3-delta) were investigated using hybrid-density-functional and density-functional-theory +U calculations. The results showed that the electron hole in LaFeO3 is more stable under a localized form and is not strictly localized on a single Fe atom. Electron hole transport is a result of onsite reorientations and hoppings. The substitution of lanthanum by strontium in LaFeO3 induces the presence of localized electron holes while preserving the insulating character. The formation energy of oxygen vacancy in La1-xSrxFeO3 was also estimated.
Article
Chemistry, Physical
A. A. Markov, S. S. Nikitin, O. Merkulov, M. Patrakeev
Summary: La0.5Sr0.5Fe0.9Mo0.1O3-delta, a perovskite-type oxide synthesized through combustion and sintering, has been characterized for its oxygen content and electrical conductivity. A model was used to simulate the defect equilibrium and determine the concentrations and mobilities of charge carriers in the oxide. Substituting molybdenum resulted in an increased concentration and mobility of n-type carriers, leading to improved electron conductivity.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Fan He, Qinning Gao, Zuoqing Liu, Meiting Yang, Ran Ran, Guangming Yang, Wei Wang, Wei Zhou, Zongping Shao
Summary: The use of a new Ba(Zr0.1Ce0.7Y0.1Yb0.1)(0.95)Pd0.05O3-delta perovskite as the key component in ammonia-fueled PCFCs improves catalytic activity for NH3 decomposition and increases proton conductivity, leading to higher power density and stability.
ADVANCED ENERGY MATERIALS
(2021)
Article
Chemistry, Inorganic & Nuclear
Xiaodong Wang, Liangliang Huang, Shufei Jiao, Honglu Li, Yifan Yang, Xuebin Jiang, Yanfeng Bi
Summary: A new zinc sulfite compound with a two-dimensional layered structure has been synthesized, showing remarkable proton conductivity depending on relative humidity.
INORGANIC CHEMISTRY COMMUNICATIONS
(2021)
Article
Chemistry, Physical
S. Kh. Estemirova, V. Ya. Mitrofanov, S. A. Uporov, G. A. Kozhina
Summary: The mechanism of formation of cation-nonstoichiometric compositions of the Tm2-xMnxO3 solid solution with a hexagonal crystal structure was studied. The role of vacancies in the Mn sublattice for the formation of compositions with an excess of Tm was analyzed. The magnetic properties of the samples were investigated and a transition from a high-temperature paramagnetic state to an antiferromagnetic state was observed.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Jiangang He, Bianca Baldassarri, Chris Wolverton
Summary: Oxygen vacancies are common defects in oxides and have important roles in various technological applications. This study compares the performance of different functionals in calculating oxygen vacancy formation energies and finds that the meta-GGA (SCAN) functional usually shows better agreement with experimental results. However, for transition metal oxides, SCAN overestimates the oxygen vacancy formation energies and requires specific parameters to reproduce experimental data.
Article
Chemistry, Inorganic & Nuclear
Hong Zhao, Zheng-Hua Du, Chen-Yu Mu, Gang Li
Summary: This study synthesized a 3D HOF and a 3D Ni(II) MOF, both of which demonstrated excellent thermal and water stability, as well as superior proton conductivity under high humidity and temperature conditions. These findings provide new inspiration for the exploration of novel proton-conductive materials.
JOURNAL OF SOLID STATE CHEMISTRY
(2022)
Article
Chemistry, Physical
Tatiana Aksenova, Darya K. Mysik, Vladimir A. Cherepanov
Summary: This study prepared a series of Gd1-xSrxCo1-yFeyO3-delta samples using a glycerol nitrate technique and investigated their structural and electrical properties. X-ray diffraction analysis revealed different crystal structures within different composition ranges, and thermogravimetric analysis was used to study the variation of oxygen content with temperature. Furthermore, measurements of relevant properties showed that Gd0.2Sr0.8Co0.3Fe0.7O3-delta exhibited the highest conductivity and predominantly p-type conductivity.
Article
Chemistry, Inorganic & Nuclear
Feten Hleli, Nicolas Mercier, Maroua Ben Haj Salah, Magali Allain, Nabil Zouari, Florian Massuyeau, Romain Gautier
Summary: Solid solutions of (Cn (1-x )Cn & PRIME; (x) )(2)PbX4 and (Cn)(2)Pb(Br1-x Cl (x) )(4) are prepared in the molten state, exhibiting tuned emission properties and modification of emission properties through the visible region.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
S. S. Nikitin, O. V. Merkulov, I. A. Leonidov, M. V. Patrakeev
Summary: The study found that Nd0.25Sr0.75FeO3-δ exhibits significant oxygen conductivity at high temperatures and good stability under reducing conditions, making it a suitable functional material for high-temperature electrochemical applications.
DALTON TRANSACTIONS
(2021)
Article
Physics, Applied
D. Wei, X. N. Ying, X. M. Lu
Summary: The effect of lattice on charge ordering in La1/3Sr2/3FeO3-d is investigated by substituting calcium ions. Cation disorder caused by size differences between La3+, Sr2+, and Ca2+ ions on the A-site is observed in La-1/3(Sr1-xCax)(2/3)FeO3-d perovskite materials. Below room temperature, a charge ordering transition is detected using temperature dependent resistivity, differential scanning calorimeter, and mechanical spectroscopy. The transition temperature T-C of charge ordering transition is dependent on the variance of A-site cation radius distribution, indicating the important role of local lattice distortions. In comparison, octahedral tilting transitions above room temperature are identified using mechanical spectroscopy, and the transition temperatures are sensitive to the average cation radius. Finally, the significance of cation disorder effect is discussed by comparing with the case in manganates.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Inorganic & Nuclear
Alyssa S. Chow, Xinyue Zhong, Douglas H. Fabini, Matthias Zeller, Catherine M. Oertel
Summary: This study reports the synthesis and characterization of a pyridinium lead bromide phase based on seven-coordinate Pb(II) centers, and examines the template role of organic cations in hybrid lead halides. The study also contributes to the characterization of isomorphic pyridinium lead chloride. The research provides insights into the synthesis and characterization of these compounds.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Jindong Cao, Kunjie Liu, Mingzhen Quan, An Hou, Xingxing Jiang, Zheshuai Lin, Jing Zhao, Quanlin Liu
Summary: Mixing cations with different chemical properties is a new approach for tuning the optical properties of hybrid organic-inorganic metal halides (HOIMHs). In this study, zero-dimensional (C9N3H15)(C9H13SO)MBr6 (M = Bi/Sb) with two different cations were synthesized, resulting in significant second harmonic generation. The synthesized compounds exhibited direct bandgaps and bright yellow emission due to fluorescence emission.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Physical
Fabian Hesse, Ivan da Silva, Jan-Willem G. Bos
Summary: Layered cobalt oxide perovskites are important conductors of both ions and electrons. In this study, the researchers investigated the characteristics of LaBaCo2O6-delta using in situ neutron powder diffraction. They found that this compound can be prepared in cubic, layered, and vacancy-ordered forms, and that layered and disordered samples have similar oxygen cycling capacities. The formation of vacancy-ordered structures leads to the emergence of additional low-energy migration pathways.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Physical
V. I. Nikolaichik, B. P. Sobolev, N. I. Sorokin, A. S. Avilov
Summary: The crystals of fluorite and tysonite phases in the BaF2-LaF3 system were studied using electron diffraction and elemental analysis. Clusters of structural defects and nanoscale ordered crystallites were found in the fluorite crystals, while the tysonite crystals showed significantly higher ionic conductivity. The similarity in defect structures between fluorite and tysonite phases may explain the increase in conductivity.
SOLID STATE IONICS
(2022)
Article
Chemistry, Physical
Jakub Kupecki, Anna Niemczyk, Stanislaw Jagielski, Ryszard Kluczowski, Magdalena Kosiorek, Krystian Machaj
Summary: This paper discusses the concept of improving the performance of solid oxide electrolyzers by adjusting the microstructure of the support materials. Instead of major redesigns, this study proposes fine-tuning the microstructure to enhance cell performance. The results show that adjusting the sintering temperature has a greater impact on the support microstructure than increasing the pore-forming agent.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Keyun Li, Anna Niemczyk, Konrad Swierczek, Anna Stepien, Yevgeniy Naumovich, Juliusz Dabrowa, Marek Zajusz, Kun Zheng, Bogdan Dabrowski
Summary: The LBCu complex oxide is evaluated as a Co-free candidate air electrode material for reversible Solid Oxide Cells (rSOC). It is structurally and thermomechanically compatible with the LSGM electrolyte and maintains a layered perovskite crystal structure at high temperatures. LBCu exhibits moderate thermal expansion and its electrical conductivity correlates with the oxygen content. Functional LBCu air electrodes can be manufactured at relatively low temperatures and exhibit low polarization resistance values.
JOURNAL OF POWER SOURCES
(2022)
Article
Chemistry, Physical
Yang Zhang, Hailei Zhao, Min Zhang, Zhihong Du, Wanbing Guan, Subhash C. Singhal, Konrad Swierczek
Summary: A novel SBMCo electrode, consisting of exsolved metallic cobalt for the anode and cobalt oxide for the cathode, is elaborately designed for symmetrical solid oxide fuel cells (SSOFCs). The results show that the rate-limiting steps for hydrogen oxidation at the anode and oxygen reduction at the cathode are significantly promoted by the exsolved nanoparticles on the SBMCo backbone, allowing the electrodes to exhibit remarkable catalytic activity.
CHEMISTRY OF MATERIALS
(2023)
Article
Thermodynamics
Justyna Sulowska, Magdalena Szumera, Dominika Madej, Bartosz Handke, Konrad Swierczek
Summary: The research aims to explain the differences between nominal and actual chemical compositions of silicate-phosphate glasses in the SiO2-P2O5-K2O-MgO-SO3 system. X-ray fluorescence (XRF) analyses were used to determine the actual compositions. Changes in the chemical composition were studied through differential scanning calorimetry-thermogravimetry-related gas analysis by mass spectrometry (DSC-TG-EGA (MS)) and high-temperature X-ray diffraction (HT-XRD). The release of gaseous products was found to be associated with changes in the chemical composition of sulfur-bearing glasses. Water vapor, carbon dioxide, carbon monoxide, and ammonia were the main gases released during thermal decomposition. Considering the potential use of these glasses as glassy fertilizers, this study is important from an environmental perspective.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Materials Science, Multidisciplinary
Marta Lubszczyk, Tomasz Brylewski, Pawel Rutkowski, Konrad Swierczek, Andrzej Kruk
Summary: A modified wet chemical method was used to prepare lead-free KNN piezoelectric ceramics, and the microstructural, dielectric, spectral, and ferroelectric properties were investigated, with specific phase transition thermal characteristics detected.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Zhao Yang, Zhaolin Li, Yaozong Yang, Qian Zhang, Hongliang Xie, Jie Wang, Konrad Swierczek, Hailei Zhao
Summary: An efficient surface modification strategy was proposed to significantly increase the initial Coulombic efficiency (ICE) of SiO anode material. SiO@Fe material with Fe nanoclusters decorating the SiO surface was successfully prepared. The well-dispersed Fe nanoclusters realized an Ohmic contact with lithium silicates, reducing electron conduction barriers and promoting lithium-ion release, leading to higher ICE of the SiO anode. The prepared SiO@Fe exhibited an unprecedented increase in ICE (23%) compared to pristine SiO, and showed improved cycling and rate performance.
Article
Chemistry, Physical
Xiaokun Pan, Boyuan Huang, Chaolei Zhang, Wanli Sun, Kun Zheng, Jiali Hu
Summary: A special engineering steel combining the properties of composite maraging steel, tool steel, structural steel, and stainless steel was designed based on a hybrid idea, and its properties and heat treatments were analyzed. The results showed that the strengthening mechanisms were dislocation strengthening and precipitation strengthening, with dislocation strengthening and precipitation strengthening accounting for 80-92% of the yield strength. By changing the microstructure through different aging treatments, the contributions of these mechanisms to the yield strength could be adjusted. The mechanical properties of the hybrid steel aged at 540 degrees C for 8 h were optimized, with an ultimate tensile strength of 2009 +/- 30 MPa and an elongation of 9.5 +/- 0.8%.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Youye Ma, Kanghui Cai, Guojie Xu, Yueling Xie, Peng Huang, Jun Zeng, Ziming Zhu, Jie Luo, Huawen Hu, Kai Zhao, Min Chen, Kun Zheng
Summary: Ultrafine PVA fibers were produced with high efficiency using a self-designed electrostatic-field-assisted centrifugal spinning system. The system improved the production efficiency by about 1000 times compared to traditional electrospinning. The spinning process parameters, including rotation speed, needle size, liquid feeding rate, and voltage, were systematically investigated, and optimized to obtain uniform ultrafine PVA fiber membranes with a diameter of 2.55 μm. The obtained ultrafine PVA fiber mat exhibited selective adsorption of NH3 gas, making it promising for NH3 storage and environmental purification applications.
Article
Chemistry, Physical
Anna Kusior, Piotr Jelen, Maciej Sitarz, Konrad Swierczek, Marta Radecka
Summary: Flower-like TiO2 nanostructures were obtained by chemical oxidation and subsequent annealing. The phase transformation of 3D flower-like titanium dioxide nanostructures was analyzed, and the effects of annealing atmosphere, sample thickness, grain shape, and nanoflower size were discussed. SEM, XRD, and Raman spectroscopy were used for characterization. The photoelectrochemical performance of the anode based on flower-like TiO2 was demonstrated, with the thickness and phase composition of the anodes being critical factors.
Article
Nanoscience & Nanotechnology
Keyun Li, Konrad Swierczek, Piotr Winiarz, Agnieszka Brzoza-Kos, Anna Stepien, Zhihong Du, Yang Zhang, Kun Zheng, Kacper Cichy, Anna Niemczyk, Yevgeniy Naumovich
Summary: The A-site cation-ordered GdBa(0.5)Sr(0.5)Co(2-x)Cu(x)O(5+δ) (GBSCC) double perovskites were evaluated as high-performance oxygen electrodes for reversible solid oxide cells (rSOCs). By substituting copper for toxic and expensive cobalt, the aim was to minimize the cobalt content while improving or maintaining the required thermomechanical and electrocatalytic properties. The study found that compositions with 1 ≤ x ≤ 1.15 were particularly interesting, exhibiting decreased thermal and chemical expansions and sufficient transport properties. The GdBa0.5Sr0.5Co0.9Cu1.1O5+δ oxygen electrode showed promising results with low electrode polarization resistance values and high power outputs, making it suitable for rSOCs.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Engineering, Chemical
Jiahe Song, Jingjing Zhang, Kun Zheng, Zhihua Xu, Kezhen Qi
Summary: As a new type of nanomaterial, graphene has been widely used in various fields and has attracted attention from researchers. In the field of photocatalysis, graphene and its composites are utilized for the degradation of organic pollutants, hydrogen production through photocatalytic water splitting, and CO2 recycling through photocatalytic reduction. Graphene-based nanomaterials also exhibit excellent antibacterial properties in the medical and pharmaceutical fields. This review provides an introduction and summary of synthesis methods, applications, and mechanisms of graphene-based photocatalysts, and highlights future research activities and potential antibacterial mechanisms.
DESALINATION AND WATER TREATMENT
(2023)
Article
Chemistry, Physical
Kun Zheng, Jakub Lach, Pawel Czaja, Michal Gogacz, Patryk Czach, Agnieszka Brzoza-Kos, Piotr Winiarz, Jie Luo
Summary: The chemical modification of perovskites through tungsten doping in Sr2Fe2-xWxO6-delta has shown significant impact on the physicochemical properties and electrochemical performance of electrode materials for solid oxide cells. A high-performance quasi-symmetrical solid oxide cell design has been proposed, demonstrating excellent power outputs and good current density in various conditions. The in situ exsolved metallic iron nanoparticles decorated on the anode contribute to the excellent electrochemical performance of cells.
JOURNAL OF POWER SOURCES
(2023)
Article
Chemistry, Physical
Maciej Mozdzierz, Zhenhe Feng, Agnieszka Brzoza-Kos, Pawel Czaja, Boyang Fu, Konrad Swierczek
Summary: Conversion-alloying-type compounds offer new possibilities as anode materials for Li-ion cells, but also have drawbacks. By studying the electrochemical processes in Zn2SnO4, important issues for practical application were identified.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
