Article
Chemistry, Physical
Xiatong Ye, Kohei Shimokawa, Yuto Kezuka, Takuya Hatakeyama, Hongyi Li, Tetsu Ichitsubo
Summary: Researchers have found that incorporating stable ZnO in Mg-Zn-Mn oxide systems can improve the phase stability of ?-MnO2, leading to highly reversible Mg insertion/extraction and increased capacity in rechargeable Mg batteries.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Xiatong Ye, Kohei Shimokawa, Yuto Kezuka, Takuya Hatakeyama, Hongyi Li, Tetsu Ichitsubo
Summary: By synthesizing equimolar mixtures of XO (X = Zn, Mg) with λ-MnO2, the stability of the spinel structure can be significantly improved, preventing the formation of an irreversible rock salt phase and decreasing the overpotential during discharge/charge cycling in Mg-Zn-Mn oxide systems.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Review
Energy & Fuels
Kiran Kumar Reddy Reddygunta, Behara Dilip Kumar
Summary: Lithium-ion batteries have been widely used in consumer electronics and energy storage due to their high energy density, but researchers are now exploring battery systems with even higher energy density. Rechargeable magnesium batteries have shown potential benefits such as low cost and high energy density, but progress has been hindered by issues with electrode kinetics and the formation of passive layers on magnesium surfaces. This chapter provides a comprehensive overview of rechargeable magnesium batteries, including advancements in electrode materials and electrolytes.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Liang Yin, Bob Jin Kwon, Yunyeong Choi, Christopher J. Bartel, Mengxi Yang, Chen Liao, Baris Key, Gerbrand Ceder, Saul H. Lapidus
Summary: The study successfully synthesized a promising high-voltage spinel oxide cathode material MgCrMnO4 with 18% Mg/Mn inversion, and designed a new custom operando battery device to investigate cation migration mechanisms. The research showed both reversible and partially reversible Mg2+ insertion in the cathode, with inverted Mn believed to be involved in cation migrations causing irreversible structural evolution. The operando techniques developed in this work could play a significant role in optimizing spinel oxide cathodes for multivalent ion batteries.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Kohei Shimokawa, Taruto Atsumi, Norihiko L. Okamoto, Tomoya Kawaguchi, Susumu Imashuku, Kazuaki Wagatsuma, Masanobu Nakayama, Kiyoshi Kanamura, Tetsu Ichitsubo
Summary: This study demonstrates a design concept for high-performance cathode materials by selecting an element to destabilize the rocksalt-type structure and utilizing the defect-spinel-type structure, leading to excellent cycle performance of magnesium rechargeable batteries.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Yunpei Zhu, Xianrong Guo, Yongjiu Lei, Wenxi Wang, Abdul-Hamid Emwas, Youyou Yuan, Yao He, Husam N. Alshareef
Summary: In this work, a aqueous Mg-ion battery chemistry involving a hydrated eutectic electrolyte and specific electrode materials was designed, which exhibits improved ionic conductivity, cycling stability, and energy density. The proposed electrolyte and electrode chemistries provide an alternative approach for developing low-cost, safe, and high-performance Mg battery technologies.
ENERGY & ENVIRONMENTAL SCIENCE
(2022)
Review
Chemistry, Physical
Kohei Shimokawa, Takuya Hatakeyama, Hongyi Li, Tetsu Ichitsubo
Summary: A wide variety of crystal structures for MnO2, called polymorphs, has potential for cathode materials in next-generation batteries. The focus of this review is on alpha-MnO2 and lambda-MnO2 structures and their criteria for achieving topotactic reactions during magnesiation. The stability of lambda-MnO2 can be improved by materials design, as demonstrated by the successful example of defect spinel ZnMnO3.
CURRENT OPINION IN ELECTROCHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
J. Alberto Blazquez, Rudi R. Maca, Olatz Leonet, Eneko Azaceta, Ayan Mukherjee, Zhirong Zhao-Karger, Zhenyou Li, Aleksey Kovalevsky, Ana Fernandez-Barquin, Aroa R. Mainar, Piotr Jankowski, Laurin Rademacher, Sunita Dey, Sian E. Dutton, Clare P. Grey, Janina Drews, Joachim Haecker, Timo Danner, Arnulf Latz, Dane Sotta, M. Rosa Palacin, Jean-Frederic Martin, Juan Maria Garcia Lastra, Maximilian Fichtner, Sumana Kundu, Alexander Kraytsberg, Yair Ein-Eli, Malachi Noked, Doron Aurbach
Summary: This article reports the first non-aqueous multilayer RMB pouch cell prototypes and proposes a roadmap for a new advanced RMB chemistry, aiming to demonstrate the great unrealized potential of RMBs.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Chemistry, Physical
Bob Jin Kwon, Liang Yin, Indrani Roy, Noel J. Leon, Khagesh Kumar, Jae Jin Kim, Jinhyup Han, Jihyeon Gim, Chen Liao, Saul H. Lapidus, Jordi Cabana, Baris Key
Summary: Inversion in spinel oxide can impede Mg2+ migration and limit its capacity. By synthesizing an inversion-free spinel and studying its reversible intercalation behavior at high redox potentials, the researchers have gained insights into Mg2+ transport and demonstrated improved electrochemical performance by reducing inversion.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Physical
Hengming Yang, Linxin He, Zhaoming Yang, Qingchun Chen, Guoquan Jiang, Junchao Zhu, Rui Xue, Nan Qiu, Yuan Wang
Summary: A dual-phase intergrown anode consisting of spinel and rocksalt phases can be prepared, leveraging the advantages of each phase and allowing for controlled electrochemical properties. This work demonstrates an effective strategy for constructing spinel-rocksalt intergrown structures, with potential implications for material design and new applications in electrochemical energy storage.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Ceramics
ChanQin Duan, Kanghui Tian, Xinglong Li, Dan Wang, Hongyu Sun, Runguo Zheng, Zhiyuan Wang, Yanguo Liu
Summary: This study synthesized high-entropy oxides with a spinel structure using a solid phase method and investigated their structure evolution and performance as electrode materials for lithium-ion batteries. The results showed that the high-entropy oxides displayed excellent cyclic stability and rate capability, with the incorporation of lithium contributing to the stabilization effect and improved lithium storage performances. The study provides a new strategy for designing high-entropy energy-storage materials and contributes to understanding the storage mechanism of HEOs.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Physical
Matthew J. A. Leesmith, Nathan R. Halcovitch, Xiao Hua
Summary: Cation disordered rocksalt (DRX) materials, prepared via heat treatment or mechanochemical synthesis, show great promise as electrode alternatives for next-generation battery technology. Recent studies have successfully prepared cation DRX oxides with desirable cycling behaviours through electrochemical lithiation of binary metal oxides. By investigating two Mn oxides with unique oxygen structures, researchers identified an electrochemically active cation DRX phase in both oxides. These findings, combined with earlier reports, provide empirical evidence for the electrochemical DRX transformation and open up new opportunities for higher energy density batteries.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Meng Huang, Xuanpeng Wang, Junjun Wang, Jiashen Meng, Xiong Liu, Qiu He, Lishan Geng, Qinyou An, Jinlong Yang, Liqiang Mai
Summary: In this study, it is found that proton co-insertion into tunnel materials is determined jointly by interface derivation and inner diffusion. The co-inserted/lattice H2O molecules block the Mg2+ diffusion while facilitate the proton diffusion. Through detailed investigations, it is demonstrated that protons dominate the subsequent insertion and inner diffusion, leading to excellent performances of the monoclinic vanadium dioxide (VO2(B)) anode in Mg(CH3COO)(2) aqueous solution.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Nanoscience & Nanotechnology
Hiroaki Kobayashi, Kouta Samukawa, Masanobu Nakayama, Toshihiko Mandai, Itaru Honma
Summary: The developed cubic MgMn2O4 spinel nanoparticles exhibit superior reversible capacity compared to tetragonal MgMn2O4 at room temperature, providing a promising cathode material for magnesium rechargeable batteries.
ACS APPLIED NANO MATERIALS
(2021)
Article
Chemistry, Physical
Zinab Jadidi, Tina Chen, Luis Barroso-Luque, Gerbrand Ceder
Summary: This study investigates the Li+ transport properties in DRX Li2-x VO3 compounds using first-principles calculations, cluster expansion techniques, and kinetic Monte Carlo simulations. The results highlight the importance of considering both tetrahedral and octahedral Li occupancy, factors influencing the diffusion coefficients with Li content, and the impact of Li+ correlated motion on Li+ transport kinetics. The study reveals that the relative stability of tetrahedral and octahedral Li determines the number of active sites within the percolation network, ultimately affecting the Li+ transport properties. Furthermore, it demonstrates that the wide site energy distribution hinders Li+ transport through correlated motion in Li2-x VO3.
CHEMISTRY OF MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Naoki Tsunoda, Yu Kumagai, Fumiyasu Oba
Summary: Hydrogen impurities in metal oxides are crucial for material properties and can have a variety of configurations, making systematic modeling challenging. This study utilizes electrostatic potential, electron localization function, and charge density to recommend interstitial hydrogen positions, showing that the approach is effective in finding stable configurations. The combination of these methods can efficiently narrow down the search space for interstitial hydrogen positions, reducing computational costs for modeling hydrogen impurities.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Physics, Applied
Hao Wang, Tetsu Ichitsubo, Hidemi Kato
Summary: The dynamic relaxation behavior of Pd42.5Ni7.5Cu30P20 metallic glass was studied at various temperatures and angular frequencies. The results show the presence of three different relaxation modes, each associated with specific activation energies and motion characteristics. These modes were also observed in the quasi-static creep compliance measurements and accurately simulated using the dynamic moduli and fitting parameters.
EUROPEAN PHYSICAL JOURNAL-APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Dina Sheyfer, Ruperto G. Mariano, Tomoya Kawaguchi, Wonsuk Cha, Ross J. Harder, Matthew W. Kanan, Stephan O. Hruszkewycz, Hoydoo You, Matthew J. Highland
Summary: Developing new methods to reveal the structure of electrode materials under polarization is crucial for establishing robust structure-property relationships. However, many existing methods lack the necessary spatial resolution and fidelity to accurately probe catalytically relevant structures. In this study, a combination of a nanopipette electrochemical cell and three-dimensional X-ray Bragg coherent diffractive imaging was used to investigate the evolution of strain in a single Pt grain under applied potential. The results demonstrated that surface strain changes during polarization are mainly caused by the Coulombic attraction between the surface charge on the electrode and the electrolyte ions, while the strain in the bulk of the crystal remains unchanged. Concurrent surface redox reactions also significantly influence the magnitude and nature of the strain changes. These findings provide valuable insights into how structural evolution affects electrochemical performance at the nanoscale.
Article
Chemistry, Physical
Yasuhide Mochizuki, Ha-Jun Sung, Tomoya Gake, Fumiyasu Oba
Summary: An evolutionary algorithm combined with first-principles calculations is used to predict the reconstructed surface structures of nonmetallic perovskite oxides. The study identifies four lowest-energy reconstruction patterns for the (001) surfaces of various perovskite oxides. The results provide general insights into the surface reconstruction and band alignment of these oxides.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Xiatong Ye, Kohei Shimokawa, Yuto Kezuka, Takuya Hatakeyama, Hongyi Li, Tetsu Ichitsubo
Summary: By synthesizing equimolar mixtures of XO (X = Zn, Mg) with λ-MnO2, the stability of the spinel structure can be significantly improved, preventing the formation of an irreversible rock salt phase and decreasing the overpotential during discharge/charge cycling in Mg-Zn-Mn oxide systems.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Takafumi Yamamoto, Shogo Kawaguchi, Taiki Kosuge, Akira Sugai, Naoki Tsunoda, Yu Kumagai, Kosuke Beppu, Takuya Ohmi, Teppei Nagase, Kotaro Higashi, Kazuo Kato, Kiyofumi Nitta, Tomoya Uruga, Seiji Yamazoe, Fumiyasu Oba, Tsunehiro Tanaka, Masaki Azuma, Saburo Hosokawa
Summary: The reaction pathway of the solid-gas reduction of layered perovskite Sr3Fe2O7-delta was revealed using high-speed time-resolved synchrotron X-ray techniques. The pristine Sr3Fe2O7-delta showed a gradual single-phase structural evolution during reduction, while a nonequilibrium dynamically-disordered phase emerged in the reduction of a Pd-loaded sample before a first-order transition. This change in reaction pathway can be explained by a change in the rate-determining step. The synchrotron X-ray technique has the potential to be applied to other solid-gas reactions for a better understanding and optimization of reactions in solid-state compounds.
Review
Chemistry, Physical
Kohei Shimokawa, Takuya Hatakeyama, Hongyi Li, Tetsu Ichitsubo
Summary: A wide variety of crystal structures for MnO2, called polymorphs, has potential for cathode materials in next-generation batteries. The focus of this review is on alpha-MnO2 and lambda-MnO2 structures and their criteria for achieving topotactic reactions during magnesiation. The stability of lambda-MnO2 can be improved by materials design, as demonstrated by the successful example of defect spinel ZnMnO3.
CURRENT OPINION IN ELECTROCHEMISTRY
(2023)
Article
Chemistry, Physical
Yue Qi, Hongyi Li, Kohei Shimokawa, Xiatong Ye, Tomoya Kawaguchi, Tetsu Ichitsubo
Summary: This study demonstrates that introducing alkali ions to construct dual-cation electrolytes can significantly improve the performance of rechargeable magnesium batteries. By satisfying two necessary conditions, namely the energetic preference of the cathode materials for Mg2+ intercalation and the coexistence of Mg2+ and alkali cations without phase separation, the discharge overpotential is reduced and the discharge capacity is increased.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Kohei Shimokawa, Shogo Matsubara, Tomoya Kawaguchi, Akihiro Okamoto, Tetsu Ichitsubo
Summary: In this study, various spinel oxide materials were investigated by modifying the composition to demonstrate their performance in photocharging. It was found that LiMn1.5Fe0.5O4 exhibited a higher discharge capacity compared to LiMn2O4 after long-term photocharging, due to its enhanced stability under illumination. This work provides fundamental design guidelines for spinel oxide cathode materials in the development of photo-rechargeable batteries.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Shigeto Hirai, Shunsuke Yagi, He-Chan Oh, Yoshiki Sato, Wei Liu, En-Pei Liu, Wei-Tin Chen, Akira Miura, Masanori Nagao, Tomoya Ohno, Takeshi Matsuda
Summary: This study successfully developed an OER catalyst with high intrinsic activity and stability under acidic conditions by preventing lattice collapse after repeated OER cycling. The substitution of Ir-sites with Mn in BaIrO3 and OER cycling led to a remarkable activity enhancement by a factor of 28 and an overall improvement in stability.
Article
Chemistry, Multidisciplinary
Yong Wang, Stephanie Bruyere, Yu Kumagai, Naoki Tsunoda, Fumiyasu Oba, Jaafar Ghanbaja, Hui Sun, Bo Dai, Jean-Francois Pierson
Summary: A joint experimental and theoretical study reveals the influence of nitrogen doping on the optical and electrical properties of NiO thin films. Nitrogen addition enhances the subgap absorption, and the presence of nitrogen molecules (N-2) in the doped films is identified through electron energy loss spectroscopy.
Article
Chemistry, Multidisciplinary
Wencong Wang, Wei Liu, Masao Kamiko, Shunsuke Yagi
Summary: This study investigates the oxygen reduction reaction (ORR) catalytic activity of an "oxygen-excess" perovskite catalyst La1-xSrxMnO3+delta and finds that it has higher activity and stability compared to a regular perovskite. Sr substitution can affect the formation of Mn4+ ions and modulate cation vacancies, thus changing the length of the Mn-O bond.
NEW JOURNAL OF CHEMISTRY
(2022)