Article
Chemistry, Inorganic & Nuclear
Masayuki Fukuda, Takumi Nishikubo, Hongwu Yu, Yoichi Okimoto, Shin-ya Koshihara, Kazunari Yamaura, Masaki Azuma
Summary: We have successfully synthesized a new A-site columnar-ordered perovskite compound, CaZnV2O6, and investigated its electronic and magnetic statesexperimentally and computationally. This compound is found to be a Pauli-paramagnetic correlated metal, providing a new playground for electronic and magnetic states of V4+.
INORGANIC CHEMISTRY
(2023)
Article
Materials Science, Multidisciplinary
Jatin Kumar Bidika, Amit Chauhan, B. R. K. Nanda
Summary: A-site ordered perovskites exhibit varying electronic and magnetic properties. This study investigates the role of Cu in these perovskites and presents the mechanism of their crystallization and stabilization of G-type antiferromagnetic ordering. The results show that the formation of A-site ordered perovskite is driven by Jahn-Teller distortion of the CuO12 icosahedron, and the magnetic ordering is robust against pressure and strain.
Article
Chemistry, Multidisciplinary
Xiaofan Shen, Fan Wang, Xiaomei Lu, Junting Zhang
Summary: We demonstrate the coexistence and coupling of ferroelectricity and ferromagnetism in designed A-site ordered perovskite oxide monolayers. The Mn-based monolayers exhibit robust ferromagnetism, while some monolayers tend to form E-type spin order. The feasibility of controlling the direction of magnetization by electric field in the monolayer limit of perovskites is demonstrated.
Article
Multidisciplinary Sciences
Jianfa Zhao, Jiacheng Gao, Wenmin Li, Yuting Qian, Xudong Shen, Xiao Wang, Xi Shen, Zhiwei Hu, Cheng Dong, Qingzhen Huang, Lipeng Cao, Zhi Li, Jun Zhang, Chongwen Ren, Lei Duan, Qingqing Liu, Richeng Yu, Yang Ren, Shih-Chang Weng, Hong-Ji Lin, Chien-Te Chen, Liu-Hao Tjeng, Youwen Long, Zheng Deng, Jinlong Zhu, Xiancheng Wang, Hongming Weng, Runze Yu, Martha Greenblatt, Changqing Jin
Summary: The A-site-ordered perovskite PbHg3Ti4O12 is the only known quadruple perovskite that undergoes a phase transition from a high-temperature centrosymmetric paraelectric phase to a low-temperature non-centrosymmetric ferroelectric phase under high pressure synthesis. It bridges the gap between simple ABO(3) perovskites and A-site-ordered AA'3Ti4O12 perovskites, exhibiting both displacive ferroelectricity and unique structural coordination.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
S. Park, C. Lee, C. Lee, T. Kim, Y. Ko, Y. Jun
Summary: Inorganic CSPI3 perovskite has gained significant attention in next-generation perovskite solar cells (PSCs) due to its suitable optical band gap and high thermal and chemical stability. However, it quickly transforms into an undesired nonperovskite yellow phase, making stabilization crucial. This paper presents an efficient method using Mn(TFSI)2 as a dopant to reduce interfacial defects and improve power conversion efficiency and long-term stability of PSCs.
MATERIALS TODAY CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Jianming Deng, Feifei Han, Bjorn Schwarz, Michael Knapp, Helmut Ehrenberg, Weibo Hua, Manuel Hinterstein, Guobao Li, Yun He, Jie Wang, Yuan Yuan, Laijun Liu
Summary: A new perovskite oxide semiconductor CaCu3Fe2Ta2O12 was synthesized with high-pressure and high-temperature method, exhibiting a quadruple perovskite structure with ordered A-sites and partially ordered B-sites. The compound shows antiferromagnetic coupling between Fe3+ spins and ferromagnetic coupling between Cu2+ spins, leading to spin ordering at around 150 K. The material has a high dielectric permittivity of approximately 2500 at room temperature, with two dielectric relaxations observed - Debye-like relaxation attributed to charge carriers trapped in oxygen vacancies at low temperatures, and Maxwell-Wagner polarization relaxation at high temperatures. Is is a new magnetic semiconductor with A-site ordering intercorrelated with second-order Jahn-Teller distortion, providing opportunities for designing novel perovskite oxides with attractive magnetic and dielectric properties.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Javier Blasco, Gloria Subias, Jose Luis Garcia-Munoz, Francois Fauth, Joaquin Garcia
Summary: In this paper, a complete structural study of the YBaMn2O6 compound with successive phase transitions is conducted, revealing distinct structural features and arrangements of Mn sites as well as increasing charge differences. The compound undergoes three consecutive phase transitions, with the emergence of new structural characteristics and increased charge segregation, indicating specific and unique properties.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Review
Chemistry, Inorganic & Nuclear
Alexei A. Belik, Roger D. Johnson, Dmitry D. Khalyavin
Summary: Perovskite-structure AMnO(3) manganites have contributed to the development of various physical concepts, while A-site-ordered quadruple perovskite manganites AMn(7)O(12) exhibit rich physics beyond the canonical materials. Recent progress in understanding them has been achieved with the wider use of high-pressure synthesis techniques.
DALTON TRANSACTIONS
(2021)
Article
Energy & Fuels
Shodruz T. Umedov, Dhruba B. Khadka, Masatoshi Yanagida, Anastasia Grigorieva, Yasuhiro Shirai
Summary: This study investigated the effects of A-site tailoring in Cs2SnI6 by adding monovalent cations such as Rb and Ag. The results showed that these additives could suppress CsI secondary phase and have a positive impact on opto-physical properties and device characteristics within a certain range.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2021)
Article
Materials Science, Multidisciplinary
J. Blasco, G. Subias, J. L. Garcia Munoz, F. Fauth, M. C. Sanchez, J. Garcia
Summary: In this study, the charge-orbital ordering and magnetic phase transitions in A-site ordered SmBaMn2O6 perovskite were investigated using synchrotron radiation x-ray powder diffraction and symmetry-adapted modes analysis. Successive phase transitions in charge, spin, and lattice degrees of freedom were observed with decreasing temperature. The two charge-ordered phases show differences in their stacking sequence along the c axis, leading to controversy in the literature.
Article
Materials Science, Multidisciplinary
Yikun Zhang, Yun Tian, Zhenqian Zhang, Youshun Jia, Bin Zhang, Minqiang Jiang, Jiang Wang, Zhongming Ren
Summary: Utilizing the magnetocaloric effects of magnetic solids, magnetic refrigeration (MR) technology has been recognized as a promising energy-efficient and environmentally friendly technology. In this study, a combined theoretical and experimental investigation of the crystal structure, magnetic properties, magnetic phase transition, and magnetocaloric performances in Gd2MgTiO6 oxide was reported. The results demonstrated the excellent magnetocaloric performances of Gd2MgTiO6 DP oxide, making it a promising candidate material for cryogenic MR applications.
Article
Chemistry, Physical
Hongping Li, Yaoming Zhang, An Sun, Baochang Guo, Yi Tian
Summary: The charge degree of freedom of A-site and B-site cations in perovskite oxides plays a crucial role in determining the internal charge distribution and generating interesting physical properties. This study discusses the magnetic couplings and electronic structures of Ce cation incorporated A-site-ordered quadruple perovskite CeMn3Mn4O12 through first-principles calculations. The results show that the A-site Ce is a magnetic cation with 4 f electrons, which is different from the nonmagnetic Ce4+ commonly found in isostructural compounds. The electronic structure analysis reveals a semiconducting to half-metallic transition accompanying with the phase transformation. Rating: 8/10.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Inorganic & Nuclear
Lalit Kumar, Joydeep Datta, Sujan Sen, Partha Pratim Ray, Tapas Kumar Mandal
Summary: A large number of quadruple perovskites are synthesized and reported under high pressure while ambient pressure synthesis of quadruple perovskites, such as LaCu3Fe2TiSbO12, has gained much interest recently. The compound shows unique structure with high dielectric constant and low loss at room temperature. Despite having a large global instability index, the stability of LaCu3Fe2TiSbO12 under ambient pressure suggests potential for discovering new quadruple perovskites.
JOURNAL OF SOLID STATE CHEMISTRY
(2021)
Article
Physics, Condensed Matter
Sumei Li, Mingfang Shu, Meng Wang, Chengbing Pan, Gaochao Zhao, Lihua Yin, Wenhai Song, Jie Yang, Xuebin Zhu, Yupin Sun
Summary: A new perovskite-type oxide, CaCu3Cr2Nb2O12, was synthesized under high pressure and temperature, and its magnetic properties were investigated. The compound exhibits a paramagnetic-ferrimagnetic transition at low temperature, showing predicted critical behavior.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Chemistry, Multidisciplinary
Makoto Iihoshi, Masato Goto, Yoshihisa Kosugi, Yuichi Shimakawa
Summary: The A-site layer-ordered double perovskite SmBaFe2O6 is synthesized by oxidizing A-site layer-ordered SmBaFe2O5 in ozone at a low temperature. This compound contains high and mixed valence Fe3.5+ and exhibits cascade charge transitions, represented as SmBa(Fe3+1.5Fe5+0.5)O6, to alleviate its electronic instability. The first Verwey-like charge-order transition occurs at 340 K, accompanied by significant structural changes and a sudden increase in magnetic susceptibility. Subsequently, a charge disproportionation of metastable Fe4+ to Fe3+ and Fe5+ takes place, resulting in an antiferromagnetic ground state. Plausible charge-ordered patterns are proposed based on electrostatic lattice energy calculations.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Materials Science, Ceramics
Kohta Nambu, Taisuke Kitaoka, Koji Morita, Kohei Soga, Tomoharu Tokunaga, Takahisa Yamamoto, Hiroshi Masuda, Hidehiro Yoshida
Summary: In this study, flash joining experiments were conducted using an AC field on 3 mol% Y2O3-stabilized tetragonal ZrO2 polycrystal (Y-TZP) bodies. The necessary conditions for achieving almost complete self-joining of Y-TZP bodies were clarified. By applying an AC field at specific conditions, successful joining with 92% of the flexural strength of the as-sintered Y-TZP body was achieved.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Youngki Yeo, Soo-Yoon Hwang, Jinwook Yeo, Jihun Kim, Jinhyuk Jang, Heung-Sik Park, Yong-Jin Kim, Duc Duy Le, Kyung Song, Moonhong Kim, Seunghwa Ryu, Si-Young Choi, Chan-Ho Yang
Summary: We report a technique for the spontaneous gathering of oxygen vacancies at strain-relaxed crack walls using flexoelectricity. Enhanced electronic conductance and a switchable diode-like feature were observed at the crack walls. The diffusivity of mobile defects in crack walls was determined to be 1.4 x 10-16 cm2/s, consistent with oxygen vacancy kinetics.
Article
Chemistry, Multidisciplinary
Dongho Kim, Jaejin Hwang, Pilgyu Byeon, Wonsik Kim, Dong Gyu Kang, Hyung Bin Bae, Sang-Gil Lee, Seung Min Han, Jaekwang Lee, Sung-Yoon Chung
Summary: Since the recognition of the significant oxygen-redox contribution to Li transition-metal oxide cathodes' capacity enhancement, the issues of oxygen release, structural variations, and capacity fading have become critical for achieving better electrochemical performance. This study utilizes nanoindentation and surface polishing to investigate the local variations of atomic structure and oxygen content in LiCoO2 and Li2MnO3. The findings provide direct evidence of oxygen release due to lattice strain and suggest the importance of efficient strain relaxation for the longevity of the anion framework in layered oxide cathodes.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Jiye Kim, Kyung-Yeon Doh, Seokho Moon, Chang-Won Choi, Hokyeong Jeong, Jaewon Kim, Wonseok Yoo, Kyungwook Park, Kyeongock Chong, Chunhyng Chung, Hanmei Choi, Si-Young Choi, Donghwa Lee, Jong Kyu Kim
Summary: We have achieved the conformal growth of sp2-hybridized few-layer h-BN on an array of Si-based nanotrenches using pulsed-mode MOCVD method. X-ray absorption fine structure spectroscopy and density functional theory calculations reveal that B-O bonds formed on the noncatalytic SiO2 surface serve as nucleation sites for the subsequent formation of mixed sp2- and sp3-hybridized BON2 and BN3. This allows for the conformal growth of few-layer sp2-hybridized h-BN with excellent step coverage, which can be used for advanced three-dimensional Si-based nanoscale architectures.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Min-Yeong Choi, Chang-Won Choi, Dong-Yeong Kim, Moon-Ho Jo, Yong-Sung Kim, Si-Young Choi, Cheol-Joo Kim
Summary: We propose a method using sodium molybdate liquid alloys to control atomic defects at grain boundaries of monolayer MoS2. The Mo-rich environment in the alloys leads to the formation of Mo-polar 5|7 defects with a yield exceeding 95%. The photoluminescence (PL) intensity of VLS-grown polycrystalline MoS(2) films is enhanced due to the suppression of nonradiative recombination of charged excitons with donor-type defects of adsorbed Na elements.
Article
Chemistry, Multidisciplinary
Un Yang, Byunghwa Kang, Moon-Jung Yong, Dong-Hwan Yang, Si-Young Choi, Jung Ho Je, Seung Soo Oh
Summary: Through nanoscale confinement, evaporation, and solidification, the direct 3D printing of intact biopolymers is demonstrated, allowing precise control of molecular-scale structures and shapes. Different biopolymers can be patterned with desired size and geometry by controlling concentrations and molecular weights, and their 3D architectures are biologically active in various solvents.
Article
Chemistry, Multidisciplinary
Changmin Lee, Youngjae Hong, Dongho Kim, Younghwan Lim, Jang Wook Choi, Sung-Yoon Chung
Summary: Protons can serve as an additional charge carrier for insertion/extraction in aqueous rechargeable batteries, alongside primary carrier cations. However, conflicting experimental results and interpretations without direct evidence have created controversy over the past decade. This study utilizes V2O5 as a model cathode and demonstrates that the insertion of protons into the cathode occurs before Zn-ions in low-pH conditions, while the influence of protons on discharge voltage and capacity is insignificant at higher pH or lower electrolyte volume.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Chang Woo Song, Jaewan Ahn, Insung Yong, Nakhyun Kim, Chan E. Park, Sein Kim, Sung-Yoon Chung, Pilnam Kim, Il-Doo Kim, Jae-Byum Chang
Summary: Biological systems are composed of hierarchical structures made of proteins. This study proposes the use of cell-derived extracellular matrix as versatile biotemplates to address the limitation of conventional biotemplates.
Article
Chemistry, Multidisciplinary
Soo-Yoon Hwang, Gyoung-Ja Lee, Yuzhao Qi, Michael Abraham Listyawan, Kyung Song, Youngho Kang, Jungho Ryu, Xiaoyan Lu, Min-Ku Lee, Si-Young Choi
Summary: In this study, a method to achieve outstanding thermal stability of converse piezoelectric constant in lead-free potassium sodium niobate (KNN)-based ceramics is proposed. The relationship between grain size and polar configuration is demonstrated, and improved thermal stability in fine grains is suggested. The thermal stability is realized in a device by successfully demonstrating the temperature dependence of piezoelectricity, making it possible to apply the lead-free piezoelectric ceramics as piezoelectric devices with high thermal stability.
MATERIALS HORIZONS
(2023)
Correction
Chemistry, Multidisciplinary
Ji-Sang An, Hae-Seung Lee, Pilgyu Byeon, Dongho Kim, Hyung Bin Bae, Si-Young Choi, Jungho Ryu, Sung-Yoon Chung
Summary: The study corrects the interstice-occupying dopant segregation at grain boundaries in perovskite oxide dielectrics and proposes a new class of ceramic capacitors.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Ji-Sang An, Hae-Seung Lee, Pilgyu Byeon, Dongho Kim, Hyung Bin Bae, Si-Young Choi, Jungho Ryu, Sung-Yoon Chung
Summary: When foreign cations are doped into ABO(3)-type perovskite oxides, they usually replace A or B sites depending on their ionic size. This study uncovers the presence of indium dopants occupying square-planar interstices and charge-compensating Ba vacancies at grain boundaries in polycrystalline BaTiO3. This chemical heterogeneity inhibits grain-boundary migration and enables the attainment of fine-grain microstructures with unprecedented dielectric properties.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Materials Science, Ceramics
Yuki Ishino, Masao Koike, Ayu Kodaira, Tomoharu Tokunaga, Takahisa Yamamoto
Summary: The development of a high-speed sintering method combining shrinkage-rate-controlled flash sintering and rapid furnace ramp has successfully produced 3YSZ sintered polycrystals with excellent mechanical properties.
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN
(2023)
Review
Materials Science, Multidisciplinary
Takahisa Yamamoto
Summary: This paper outlines the development and challenges of flash sintering and introduces an improved version of flash sintering.
MATERIALS TRANSACTIONS
(2023)
