Article
Materials Science, Ceramics
R. Z. Huang, Y. Y. Wei, T. F. Gao, C. M. Li, C. H. Jiang
Summary: Investigations on vacancy-ordered structures of pure and doped delta-Bi2O3 reveal that the structure with combined <110> and <111> vacancy arrangements is energetically favorable. Different doping ions tend to occupy specific sites, with larger ions favoring Bi(2) sites and smaller ions favoring Bi(1) sites. The electronic structure of oxides can be tuned by vacancy and interstitial defects to enhance conductivity and photocatalytic properties.
CERAMICS INTERNATIONAL
(2021)
Article
Crystallography
Namrata Dewan Soni, Jyoti Bhola
Summary: This study introduces the first-ever optimized surface acoustic wave (SAW) device based on Beryllium Oxide (BeO) thin film, and theoretically examines the feasibility of SAW devices with BeO/128 degrees YX LiNbO3 layered structure. The calculated results show that the BeO/128 degrees YX LiNbO3 layered structure demonstrates optimal phase velocity and coupling coefficient when the BeO over layer thickness reaches 0.08 lambda, and temperature stability can be achieved by integrating it with a negative temperature coefficient of delay (TCD) TeO3 over layer.
Article
Chemistry, Multidisciplinary
Hui Zhang, Madisen Holbrook, Fei Cheng, Hyoungdo Nam, Mengke Liu, Chi-Ruei Pan, Damien West, Shengbai Zhang, Mei-Yin Chou, Chih-Kang Shih
Summary: The synthesis of a single atomic sheet of honeycomb structure BeO (h-BeO) grown on Ag(111) thin films on Si(111) wafers using molecular beam epitaxy (MBE) is reported. The h-BeO has a lattice constant of 2.65 A and an insulating band gap of 6 eV. Weak interaction between h-BeO layer and Ag(111) substrate is found, making h-BeO an attractive candidate for future technological applications.
Article
Materials Science, Multidisciplinary
Vishal Zade, Roy Swadipta, C. Ramana
Summary: The effect of transition metal ion mixing on the crystal structure, surface morphology, microstructure, and optical properties of gallium oxide has been studied. Different transition metals (Fe, Ti, W) incorporation significantly influences the structural and optical properties of Ga2O3, with marked differences in solubility limit among Fe, Ti, and W ions.
Article
Chemistry, Multidisciplinary
Mihail Lungu, Daniel Cristea, Flaviu Baiasu, Cornel Staicu, Alexandru Marin, Oana Gloria Pompilian, Bogdan Butoi, Claudiu Locovei, Corneliu Porosnicu
Summary: The direct current and radio frequency magnetron sputtering methods were used to deposit structural materials. Different configurations were evaluated for surface topology, thermal desorption outgassing, structural and chemical state, and mechanical properties. The composite layers of Cr2O3 with Be and W exhibited the best microstructure and surface state.
Article
Materials Science, Multidisciplinary
Shoroog Alraddadi
Summary: The study revealed that multilayer ultrathin films of epitaxial maghemite possess good magnetic properties close to bulk values, with magnetic moment increasing as the number of layers increases, which could be utilized in developing spintronic devices and other technological applications.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2021)
Article
Physics, Multidisciplinary
Chang-Jong Kang, Gabriel Kotliar
Summary: The study reveals the optical properties of the infinite-layer La1-xSrxNiO2 in its normal state, showing a correlated metal state with unique behaviors compared to density functional theory, such as decreasing integrated optical spectral weight with doping and increasing temperature. The effective crystal field splitting is found to be dynamic, leading to the formation of a Hund's metallic state with dynamic orbital fluctuations at intermediate energies.
PHYSICAL REVIEW LETTERS
(2021)
Article
Crystallography
Oluwagbemiga P. Ojo, Winnie Wong-Ng, Tieyan Chang, Yu-Sheng Chen, George S. Nolas
Summary: Single crystals of a new ternary chalcogenide Cu3InSe4 were successfully synthesized by induction melting, and their crystal structure was thoroughly investigated using high-resolution single-crystal synchrotron X-ray diffraction. The results reveal that Cu3InSe4 crystallizes in a cubic structure with three unique crystallographic sites. The chemical bonding nature was studied using electron localization function calculations, and first-principle electronic structure calculations were also performed.
Article
Optics
Abdelhafid Najim, Omar Bajjou, Mustapha Boulghallat, Mohammed Khenfouch, Khalid Rahmani, Younes Chrafih
Summary: This article investigates the influence of porphyrin on the crystallinity, electronic structure, and optical properties of graphene oxide using DFT. Theoretical calculation shows that porphyrin substitution leads to significant distortion in the GO sheet and decreases the bandgap. Substitution also affects the absorption coefficient, decreasing it in the UV domain and increasing it in the visible range. The substitution of porphyrin chain on the GO sheet improves the power conversion efficiency of solar cells.
Article
Chemistry, Inorganic & Nuclear
Fatima Safieddine, Fouad El Haj Hassan, Michel Kazan
Summary: In this study, the FP-LAPW thorn lo method was used to investigate the properties of Ga2O3, including structural, electronic, elastic, optical, thermodynamic, and transport properties. The results show that Ga2O3 has potential applications in optoelectronics and thermoelectrics.
JOURNAL OF SOLID STATE CHEMISTRY
(2022)
Article
Materials Science, Multidisciplinary
Shashank Inge, Adityanarayan Pandey, Udayan Ganguly, Amrita Bhattacharya
Summary: This paper focuses on resistive-switching-based memory, which is a popular research area for neuromorphic, nonvolatile memory design and in-memory computing. The study reveals that the activation energies for the migration of charged oxygen vacancies (V-O(q)) in Pr1-xCaxMnO3 [PCMO(x)] vary significantly, making it difficult to understand the resistive switching properties of PCMO(x)-based memory.
Article
Chemistry, Multidisciplinary
Eufrasia S. Pereira, Gabriel L. S. Rodrigues, Willian R. Rocha
Summary: NO uptake by the Ru-based anticancer metallodrug NAMI-A takes place at the triplet potential energy surface with a small energy barrier and is thermodynamically favorable, supporting the anti-angiogenesis theory associated with NAMI-A's mode of action.
Article
Chemistry, Multidisciplinary
Jianfeng Su, Jiao Zhang, Yajie Wang, Changqing Wang, Qiang Niu, Ruirui Sun, Weiying Zhang
Summary: Cu2O is a good photoelectric material with excellent performance, and its crystal structure, electronic structure, and optical properties have been extensively studied. The e-h recombination dynamics in this system was investigated to illustrate the charge distribution and carrier transport. N doping induced a shallower impurity band above the VBM, leading to significant charge localization. NAMD simulation showed that the N doping system has a longer e-h nonradiative recombination time scale. The formation of the impurity band and charge localization are demonstrated to play an essential role in suppressing e-h recombination in N doping systems. This work contributes to understanding the carrier transport mechanism in N-doped Cu2O.
Article
Engineering, Electrical & Electronic
Haiwan Xu, Rui Wu, Jia-Ye Zhang, Wenqiao Han, Lang Chen, Xuan Liang, Choon Y. Haw, Piero Mazzolini, Oliver Bierwagen, Dong-Chen Qi, Kelvin H. L. Zhang
Summary: In this study, the electronic structure of CuFeO2 was directly investigated using resonant photoemission spectroscopy and X-ray absorption spectroscopy. It was found that CuFeO2 has an indirect and d-d forbidden band gap of 1.5 eV, and the localized nature of Fe 3d states at the edges of the valence and conduction bands limits carrier mobility.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Jicheng Zhang, Deniz Wong, Qinghua Zhang, Nian Zhang, Christian Schulz, Maciej Bartkowiak, Ke An, Lin Gu, Zhongbo Hu, Xiangfeng Liu
Summary: By atomically engineering high-spin LCO, a tuned redox mechanism with only Co redox is demonstrated, which fundamentally addresses the issues of oxygen release and structural degradation in high-voltage LiCoO2.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Physics, Applied
D. V. Suetin, I. R. Shein
JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM
(2018)
Article
Materials Science, Ceramics
V. P. Zhukov, V. N. Krasil'nikov, A. P. Tyutyunnik, T. V. Dyachkova, N. A. Zhuravlev, A. V. Skachkov, T. A. Denisova, I. R. Shein
CERAMICS INTERNATIONAL
(2018)
Article
Chemistry, Inorganic & Nuclear
Aleksei G. Krasnov, Mania S. Koroleva, Maxim Vlasov, Igor R. Shein, Irina Piir, Dina G. Kellerman
INORGANIC CHEMISTRY
(2019)
Article
Chemistry, Physical
A. G. Krasnov, A. A. Kabanov, N. A. Kabanova, I. V. Piir, I. R. Shein
SOLID STATE IONICS
(2019)
Article
Chemistry, Physical
V. P. Zhukov, B. Politov, A. Yu Suntsov, I. A. Leonidov, I. R. Shein, V. L. Kozhevnikov
SOLID STATE IONICS
(2020)
Article
Chemistry, Inorganic & Nuclear
Aleksei G. Krasnov, Maxim S. Napalkov, Maxim Vlasov, Mariia S. Koroleva, Igor R. Shein, Irina Piir
INORGANIC CHEMISTRY
(2020)
Article
Chemistry, Physical
M. S. Koroleva, A. G. Krasnov, A. Senyshyn, A. Schoekel, I. R. Shein, M. Vlasov, I. Piir
Summary: Experimental and theoretical investigations were conducted on novel bismuth niobates with pyrochlore structure, showing the effects of Na and Mg doping on their crystal structure, thermal stability, and electrical properties. The results indicated that the band gap values and electrical properties of the compounds were influenced by the concentrations of Na and Mg dopants in the structure.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Mariia S. Koroleva, Aleksei G. Krasnov, Anatoliy Senyshyn, Alexander Schoekel, Igor R. Shein, Maxim Vlasov, Irina Piir
Summary: New pyrochlore-structured compounds Bi1.5Mg0.9-xLixNb1.5O7-delta (x = 0.25; 0.40) and Bi1.4RE0.1Mg0.5Li0.4Nb1.5O7-delta (RE - Eu, Ho, Yb) were synthesized and their atomic displacements and dopant distribution were studied. The preferred model with a direct band gap of 3.18 eV was predicted, and the thermal stability of the compounds was determined. Charge disbalance and oxygen vacancies were found to affect the dielectric behavior and conductivity of the ceramics.
MATERIALS RESEARCH BULLETIN
(2022)
Article
Chemistry, Physical
A. G. Krasnov, M. S. Koroleva, I. Piir, I. R. Shein
Summary: A detailed study combining density functional theory (DFT) and experiments was conducted on the substitution of Li and Na in Bi2Ti2O7 pyrochlore (BTO). The study showed that Na-doped BTO pyrochlores can only be obtained at low sodium content, while Li-doped BTOs can be synthesized at various lithium content. The doped pyrochlore compositions were found to be wide-band indirect semiconductor materials with good conductivity. The experimental results confirmed the predictions from the DFT simulations.
SOLID STATE IONICS
(2022)
Article
Chemistry, Inorganic & Nuclear
Mariia S. Koroleva, Aleksey V. Ishchenko, Maxim I. Vlasov, Aleksei G. Krasnov, Elena I. Istomina, Igor R. Shein, Ilya A. Weinstein, Irina V. Piir
Summary: Eu-doped bismuth-based pyrochlore ceramics were synthesized using the organic-inorganic precursor combustion technique. The study investigated the effect of Eu3+ doping on the structural, dielectric, optical, and luminescence properties, and found that Eu3+ doping caused structural distortion and decreased dielectric permittivity. Additionally, the study also demonstrated the influence of Li and Na content, additional phases, and dopant concentration on the material properties.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Natalia V. Chezhina, Irina V. Piir, Aleksei G. Krasnov, Mariia S. Koroleva, Dina G. Kellerman, Valentin G. Semenov, Elizaveta V. Shalaeva, Ivan I. Leonidov, Igor R. Shein
Summary: The nanoparticles of pyrochlore Bi1.5Fe0.5Ti2O7-delta were prepared and characterized using various techniques. The distribution and behavior of Fe atoms in the nanosized Bi1.5Fe0.5Ti2O7-delta were investigated. The study showed that the local microstructure of the metastable nanosized sample determined the local distribution, electronic structure, and magnetic behavior of Bi1.5Fe0.5Ti2O7-delta.
INORGANIC CHEMISTRY
(2022)
Article
Physics, Multidisciplinary
N. S. Pavlov, I. R. Shein, K. S. Pervakov, I. A. Nekrasov
Summary: A comparative analysis of electronic structures of possible isostructural analogues of iron superconductors InCo2As2 and KInCo4As4 with BaFe2As2 was conducted using DFT/LDA and LDA + DMFT approaches. Results showed relatively small quasiparticle mass renormalization at the Fermi level, and significant shifts and compressions of the spectrum below -0.8 eV due to correlation effects. The band structure of InCo2As2 resembled BaCo2As2, while KInCo4As4 showed similarities with the band structure and Fermi surfaces of BaFe2As2, suggesting the possibility of superconductivity. Furthermore, LDA + DMFT calculations indicated topological Lifshitz transitions under hole or electron doping in KInCo4As4. The synthesis of InCo2As2 and KInCo4As4 compounds is crucial for studying superconductivity in this class of materials.
Article
Chemistry, Inorganic & Nuclear
I. R. Shein
Summary: In this study, the electronic structures and chemical bonding parameters of Th-B systems (ThB4, ThB6, and ThB12 structures) were investigated using ab initio methods and considering relativistic effects. The behavior of formation energy in relation to the partial content of boron was also examined.
JOURNAL OF STRUCTURAL CHEMISTRY
(2022)
Article
Chemistry, Physical
B. V. Politov, J. C. Waerenborgh, I. R. Shein, O. V. Merkulov
Summary: The crystalline and electronic band structures, thermodynamic stability, oxygen non-stoichiometry and high-temperature transport properties of perovskite-like solid solutions Sr1-yFe0.5-xTa0.5+xO3-delta have been thoroughly studied. It is found that intentionally introducing defects in the strontium sublattice can stabilize the oxides with excess tantalum content. The charge states in the iron sublattice are mainly Fe3+ ions, and the band structure calculations support the semiconducting nature of electrical transport. The overall defect structure heavily relies on oxygen vacancy formation processes. Increasing the tantalum content improves the oxygen non-stoichiometry and conductive properties of the materials.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
I. R. Shein, V. V. Novikov, S. Kuznetsov, K. Ponkratov, A. Matovnikov, N. Mitroshenkov, B. Kornev, A. Morozov, V. L. Prishchep, S. L. Bud'ko
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2019)
