Article
Materials Science, Ceramics
Ji Li, Shoufu Yu, Lei Bi
Summary: A new BSZF material was proposed as a cathode for proton-conducting SOFCs. The incorporation of Sr into the lattice improved the chemical stability and enhanced the oxygen vacancy content, leading to improved performance of the fuel cell.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Chengzhi Sun, Yu Kong, Yongchao Niu, Xiaoju Yin, Naiqing Zhang
Summary: As a classical family of high-performance cathode materials, mixed ionic and electronic conductor (MIEC) is crucial for the low-temperature operation and high efficiency of solid oxide fuel cells. While Fe-based double perovskites have advantages of low cost, good thermal compatibility with the electrolyte, and high-temperature stability, their electrochemical properties for oxygen reduction reaction are unsatisfactory. This study demonstrates that substituting Zr for Fe in NdBaFe2O6??Δ (NBF) lattice can enhance oxygen vacancy concentration and the position of O p-band center, leading to improved oxygen reduction performance for the Zr-doped NBF cathode.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Electrochemistry
Xinmin Fu, Xiangwei Meng, Shiquan Lu, WeiJiang Gong
Summary: In this study, Sm0.5Sr0.5Co1-xBixO3-δ (SSCB, x = 0.00-0.10) nanofiber cathode materials were prepared by electrospinning for solid oxide fuel cells (SOFCs). The SSCB nanofibers exhibited orthorhombic perovskite structures according to XRD analysis. XPS analysis confirmed the presence of Sm3+, Sr2+, Co3+/Co4+, and Bi3+ species in the SSCB samples. The nanofiber cathodes of SSCB heated at 900 degrees C showed a homogeneous porous microstructure and good contact with the Sm0.2Ce0.8O1.95 (SDC) electrolyte. Among the samples, the SSCB nanofiber cathode with x = 0.07 showed the lowest polarization resistance (Rp) at various temperatures, and the anode-supported single cell with this cathode achieved a peak power density (PPDs) of 1.16 W cm-2 at 750 degrees C. These findings suggest the potential of nanofiber SSCB oxides as cathode materials for SOFCs.
ELECTROCHIMICA ACTA
(2023)
Article
Materials Science, Ceramics
Birkneh Sirak Teketel, Bayu Admasu Beshiwork, Xiaoyan Luo, Dong Tian, Shiyue Zhu, Halefom G. Desta, Quan Yang, Yonghong Chen, Bin Lin
Summary: By employing an A-site doping strategy, higher-oxygen-vacancy cobalt-free layered perovskite cathodes for high-performing protonic ceramic fuel cells at reduced temperatures are achieved. Both Nd and K doping significantly improve the electrical conductivities of the cathodes and promote the single-cell output performance.
CERAMICS INTERNATIONAL
(2022)
Article
Nanoscience & Nanotechnology
Kaixuan Ma, Qian Li, Cheng Hong, Gongzheng Yang, Chengxin Wang
Summary: The study synthesized bismuth-doped alpha-MnO2 using a hydrothermal method, which effectively enlarged lattice spacing and improved the electrochemical performance of Zn/MnO2 batteries. The Bi-doped alpha-MnO2 cathode exhibited high reversible specific capacity and long cycling stability, offering a new perspective to enhance the electrochemical properties of Zn/MnO2 batteries.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Materials Science, Ceramics
Shoufu Yu, Xuan Yang, Yu Wang, Lei Bi
Summary: In this study, U cations were immobilized in the traditional SFO oxide, resulting in the formation of an improved SFUO material. Experimental results showed that SFUO had better chemical stability and surface catalytic activity, making it suitable for proton-conducting solid oxide fuel cells. The use of SFUO as a cathode led to higher fuel cell output and lower polarization resistance.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Quan Yang, Guoqing Wang, Haodong Wu, Bayu Admasu Beshiwork, Dong Tian, Shiyue Zhu, Yang Yang, Xiaoyong Lu, Yanzhi Ding, Yihan Ling, Yonghong Chen, Bin Lin
Summary: The high-entropy cathode HEP has shown outstanding electrochemical performance in SOFCs, indicating promising potential applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Multidisciplinary
Hongfei Chen, Zhe Lu, Zhipeng Liu, Yujie Wu, Shuai Wang, Zhihong Wang
Summary: Tuning the Fe-site element type of PrFeO3-delta through Sr and Nb co-doping enhances its anodic catalytic performance and maintains structural stability.
Article
Materials Science, Ceramics
K. H. Tan, H. A. Rahman, M. S. Azami, U. A. Yusop, N. A. Baharuddin, M. I. Nor Ma'arof
Summary: This paper presents the development and characterization of a new composite cathode material BSCF-SDCC for low-temperature solid oxide fuel cell cathode application. The BSCF-SDCC composite cathode demonstrated excellent microstructural, chemical, and electrochemical properties. The composite cathode exhibited low polarization resistance and high conductivity, making it a promising candidate for low-temperature solid oxide fuel cell cathodes.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Jie Gao, Shuai Xu, Muhammad Akbar, Chen Xia, Wenjing Dong, Chongqing Liu, Yuanjing Meng, Menghui Yuan, Baoyuan Wang, Xunying Wang
Summary: This research introduces a single-layer solid oxide fuel cell based on semiconductor-ionic conductor composite material, demonstrating high performance stability and greater tolerance for temperature changes.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Wenjing Dong, Ziwei Xiao, Mengling Hu, Ruineng Ruan, Shuo Li, Xunying Wang, Chen Xia, Baoyuan Wang, Hao Wang
Summary: This study investigated the use of semiconductor-ionic conductor membrane (SIM) in solid oxide fuel cells (SOFCs) and found that utilizing semiconductor La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF) and ionic conductor Sm-doped cerium oxide (SDC) as the SIM layer can achieve high performance. The study analyzed the impact of LSCF content and NCAL electrode on membrane conductivity, as well as the formation of melting alkali metal compounds in the SIM layer during cell operation, providing important insights for improving cell performance.
JOURNAL OF POWER SOURCES
(2021)
Article
Chemistry, Physical
Jiyang Ma, Yuxin Pan, Yakun Wang, Yu Chen
Summary: This study presents a Sr and Ni dual doped Ruddlesden-Popper perovskite oxide, La1.6Sr0.4Cu0.6Ni0.4O4+delta (LSCN), with rich oxygen vacancies and good chemical/thermal compatibility with the electrolyte. The LSCN cathode showed promising electrochemical performance with peak power density of 1020 mWcm(-2) and excellent stability at 750 degrees C over a period of 100 hours, making it a potential cathode material for protonic ceramic fuel cells.
JOURNAL OF POWER SOURCES
(2021)
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
Chemistry, Physical
Takaaki Sakai, Masako Ogushi, Kohei Hosoi, Atsushi Inoishi, Hidehisa Hagiwara, Shintaro Ida, Masatsugu Oishi, Tatsumi Ishihara
Summary: YCoO3 is discussed as a novel cathode material for solid oxide fuel cells (SOFCs) due to its stable characteristics and ability to enhance cathodic performance without significant reaction with YSZ electrolyte.
JOURNAL OF MATERIALS CHEMISTRY A
(2021)
Article
Chemistry, Physical
Shubhangi Khadtare, Anuruddh Kumar, Uijin Jung, Chengwen Sang, Jinsub Park
Summary: This work reports the synthesis of Bi1-xSrxFeO3 (SBFO; x = 0.0, 0.15, 0.25, 0.35) nanoparticles by solgel method and investigates their structural and piezoelectric properties. The study reveals the phase transformation from rhombohedral to cubic of BiFeO3 upon Sr doping, as well as the enrichment of oxygen vacancies in Sr-doped BiFeO3 nanoparticles. The SBFO-PENG device with 25% Sr content shows the highest maximal polarization value and remnant polarization, along with improved output voltage and current compared to a bare BiFeO3 PENG. It also demonstrates high mechanical robustness and stable output even after extended periods of operation. The feasibility of the SBFO-PENG device is demonstrated by successfully triggering commercial electronics and energy storage in a capacitor.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Akihiro Ishii, Mina Yamaguchi, Itaru Oikawa, Yusuke Yamazaki, Masaaki Imura, Toshimasa Kanai, Hitoshi Takamura
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2020)
Article
Chemistry, Physical
Mina Yamaguchi, Akihiro Ishii, Itaru Oikawa, Hitoshi Takamura
APPLIED SURFACE SCIENCE
(2020)
Article
Multidisciplinary Sciences
Shenghan Gao, Thibault Broux, Susumu Fujii, Cedric Tassel, Kentaro Yamamoto, Yao Xiao, Itaru Oikawa, Hitoshi Takamura, Hiroki Ubukata, Yuki Watanabe, Kotaro Fujii, Masatomo Yashima, Akihide Kuwabara, Yoshiharu Uchimoto, Hiroshi Kageyama
Summary: Most solid-state materials are made up of p-block anions, but the introduction of hydride anions (1s(2)) in oxides has led to the discovery of interesting properties. By combining hydride anions with chalcogenide anions, a family of antiperovskites has been created with soft anionic sublattices. The M(3)HCh antiperovskites (M=Li, Na) exhibit ideal cubic structures, showing low migration barriers for Li+/Na+ transport and high ionic conductivity.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Hiroaki Kawamori, Itaru Oikawa, Hitoshi Takamura
Summary: This study achieved highly hydrated perovskite-type oxide through high-pressure synthesis, increasing proton concentration by utilizing Sc vacancies and excess protons. A novel mechanism to enhance proton concentration of perovskite-type proton conductors was revealed by compensating B-site charge with protons residing in Sc vacancies and extensive hydration conditions. The electrical conductivity at 450-500 degrees C was comparable to that of acceptor-doped BaZrO3, with a discontinuous change at dehydration temperature.
CHEMISTRY OF MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Mina Yamaguchi, Akihiro Ishii, Itaru Oikawa, Yusuke Yamazaki, Masaaki Imura, Hitoshi Takamura
Summary: Thin films of 60 mol % Ag-40 mol % (Fe1-xAlx)-O prepared by pulsed laser deposition exhibit promising optical properties, electrical resistance, and thermal stability, demonstrating their potential as black AR coatings.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Materials Science, Multidisciplinary
Akihiro Ishii, Hibiki Ishijima, Kosei Kobayashi, Itaru Oikawa, Hitoshi Takamura
Summary: The key element for low-temperature sintering of Sm-doped CeO2 was found to be aluminum, which was spontaneously introduced through a chemical reaction with mixed lithium and alumina crucible. Zirconium was also introduced through ball-mill processing. Both aluminum and zirconium play an important role in reducing the melting point and achieving low-temperature sintering.
Article
Engineering, Multidisciplinary
Zaka Ruhma, Keiji Yashiro, Itaru Oikawa, Hitoshi Takamura, Tatsuya Kawada
Summary: This study focuses on the effects of pore former in metal slurry on the sintered layer of metal-supported SOFC, showing that changing the amount of pore former in the slurry can alter the sinterability of the metal layer and subsequently impact the final warpage state of the cell. The research helps in understanding the sintering phenomena between layers of metal-supported SOFCs.
JOURNAL OF ENGINEERING AND TECHNOLOGICAL SCIENCES
(2021)
Article
Nanoscience & Nanotechnology
Mina Yamaguchi, Akihiro Ishii, Itaru Oikawa, Yusuke Yamazaki, Masaaki Imura, Hitoshi Takamura
Summary: In this study, black antireflective (AR) coatings with electric insulative properties were developed for touch panel displays. The multilayer black AR stacks showed low reflectance and transmittance over the whole visible range, making them suitable for improving visibility and appearance of the displays.
Article
Chemistry, Multidisciplinary
Daichi Kato, Osamu Tomita, Ryky Nelson, Maria A. Kirsanova, Richard Dronskowski, Hajime Suzuki, Chengchao Zhong, Cedric Tassel, Kohdai Ishida, Yosuke Matsuzaki, Craig M. Brown, Koji Fujita, Kotaro Fujii, Masatomo Yashima, Yoji Kobayashi, Akinori Saeki, Itaru Oikawa, Hitoshi Takamura, Ryu Abe, Hiroshi Kageyama, Tatiana E. Gorelik, Artem M. Abakumov
Summary: Layered bismuth oxyhalides with bilayered (Bi2O2) fluorite slabs are promising visible-light photocatalysts due to their excellent stability and the ability to adjust band levels. Manipulating the Bi2O2 slab allows control over the structure and properties, creating new research opportunities.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Satoru Tanaka, Akihiro Ishii, Mina Yamaguchi, Itaru Oikawa, Yusuke Yamazaki, Masaaki Imura, Hitoshi Takamura
Summary: In this study, black and electrically insulating Ag-Fe2O3-based coatings were prepared using reactive magnetron sputtering, stainless steel, and silver foil. The thin films showed blue light absorption and high electrical resistance comparable to Fe2O3 single crystals. By controlling the percentage of Ag in the film samples and the oxygen introduction, black and electrically insulating thin films composed of metallic Ag, amorphous Ag-Fe-O, and slightly crystallized Fe2O3 were obtained. The phase separation mechanism based on thermodynamic nonequilibrium oxidation of the metallic Ag phase was proposed.
Article
Nanoscience & Nanotechnology
Akihiro Ishii, Natsumi Nemoto, Mina Yamaguchi, Kosei Kobayashi, Itaru Oikawa, Akira Takano, Takuma Hitomi, Naohiro Hayashi, Hitoshi Takamura
Summary: The development of efficient and stable oxygen-reducing electrodes is crucial for efficient electrochemical cells. Composite electrodes composed of La(1-x)Sr(x)Co(1-y)Fe(y)O(3-δ) and doped CeO2 are considered promising for solid oxide fuel cells. This study demonstrates that the segregation of catalytic cobalt oxides and oxide-ion conducting paths greatly impacts the performance of the composite electrodes. By controlling the segregation process, microstructure, and phase evolution, stable low-resistance composite oxygen-reducing electrodes can be fabricated.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Electrochemistry
Youtaro Sakamoto, Akihiro Ishii, Takashi Shiratori, Itaru Oikawa, Hitoshi Takamura
Summary: Researchers developed a composite electrolyte consisting of conductive Li7La3Zr2O12 (LLZ) and sintering-free LiBH4, which is compatible with Li metal anodes. LLZ powder prepared by hand milling produced dense LLZ-LiBH4 composite. The LLZ-LiBH4 composite did not form secondary phases at a magic-angle-spinning nuclear magnetic resonance level. LiBH4 filled the space between LLZ particles up to a volume fraction of LLZ to 0.8, and the total ionic conductivity increased with increasing LLZ fraction. The LLZ-LiBH4 composite exhibited 670 times higher room-temperature ionic conductivity than LiBH4 alone. The Li+ conduction behavior of the LLZ-LiBH4 composite changed by the phase transition of LiBH4 to a high-temperature conductive phase. The current tolerance of Li|LLZ-LiBH4 composite|Li cell was comparable to that of a cell using a well-sintered LLZ electrolyte, indicating its potential use with Li metal anode.
ELECTROCHIMICA ACTA
(2023)
Article
Chemistry, Physical
Kazuto Murakami, Yoko Sugawara, Junki Tomita, Akihiro Ishii, Itaru Oikawa, Hitoshi Takamura
Summary: It has been found in the study that co-doped Ce-Zr-based oxides with Co and Fe have high oxygen storage capacity at low temperatures. The presence of Fe induces phase transition and formation of an intermediate phase, improving the oxygen storage performance of the material.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Materials Science, Multidisciplinary
Hiroshi Tanimura, Norihiko L. Okamoto, Takao Homma, Yusuke Sato, Akihiro Ishii, Hitoshi Takamura, Tetsu Ichitsubo
Summary: This study investigates the ultrafast optical response of VTe2 and reveals the photoinduced phase transition process. It suggests that the high-temperature phase of VTe2 is induced within a picosecond through purely electronic effect and the phase transition dynamics proceed inhomogeneously via a nucleation mode.
Article
Chemistry, Physical
Hiroki Uehara, Akihiro Ishii, Itaru Oikawa, Hitoshi Takamura
Summary: A new mixed proton-hole conducting material is developed by doping cobalt into BaZr1-xScxO3-delta, which exhibits high hole conductivity. The study investigates the phases present, proton incorporation, and electrical conductivity of BaCoxZr0.9-xSc0.1O3-delta. It is found that Sc doping increases the cobalt solubility limit in BaZrO3 and conductive protons are incorporated in the bulk portion of Co, Sc-doped BaZrO3. BaCoxZr0.9Sc0.1O3-delta shows higher conductivity than Fe or Pr doped BaMxZr1-x-yYyO3-delta. The maximum conductivity is achieved for BaCo0.2Zr0.7Sc0.1O3-delta in both wet and dry oxidizing atmospheres.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
