Article
Physics, Applied
Hao-Cheng Thong, Ben Xu, Ke Wang
Summary: This study investigates different types of domain walls in niobate-based ferroelectric perovskite KNbO3 using first-principles calculations, and finds that Nb-O hybridization plays a critical role in the formation and motion of domain walls.
APPLIED PHYSICS LETTERS
(2022)
Article
Electrochemistry
Jiayu Wang, Xuena Wu, Xifeng Lu, Zhen Xu, Haihui Jiang, Libin Liu, Qing Ban, Ligang Gai
Summary: This paper reports on the significant improvement in electrochemical performance of gallium oxynitride (GON) nanoparticle-based electrodes by introducing both cation and anion defects via controllable electrochemical etching. The textural property, band structure, and defect concentration of the electrodes can be engineered by altering the etching time. The enhanced electrochemical performance is attributed to the elimination of surface oxide layer, improved specific surface area and pore volume, as well as engineered cation and anion defects.
ELECTROCHIMICA ACTA
(2022)
Article
Chemistry, Physical
Atsushi Takagaki, Shohei Nakamura, Shu Ashimura, Masaaki Yoshida, Jun Tae Song, Motonori Watanabe, Shigenobu Hayashi, Tatsumi Ishihara
Summary: Porous boron nitride was synthesized using boric acid with urea and/or hexamethylenetetramine (HMTA) via pyrolysis method. The synthesized boron nitride has a turbostratic structure with both amino and hydroxyl groups on the surface. The mixture of two nitrogen-containing precursors not only significantly increases the porosity, but also improves the surface functionality.
APPLIED CATALYSIS A-GENERAL
(2022)
Article
Multidisciplinary Sciences
Abhijit H. Phakatkar, Tolou Shokuhfar, Reza Shahbazian-Yassar
Summary: By utilizing electron energy loss spectroscopy, the oxidation state of solid solution polyelemental transition metal oxide nanoparticles was studied, revealing that random mixing in solid solution phase not only enhances entropy stabilization but also leads to stable oxidation states in transition metals ranging from binary to quinary transition metal oxides.
Article
Chemistry, Physical
Robert A. Lawrence, Quentin M. Ramasse, Kristina M. Holsgrove, Daniel Sando, Claudio Cazorla, Nagarajan Valanoor, Miryam A. Arredondo
Summary: The role of local chemical environments in the electron energy loss spectra of complex multiferroic oxides was studied using computational and experimental techniques. It was found that chemical variation had a major impact on the spectral features, while strain induced only a small chemical shift.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Inorganic & Nuclear
Takuya Sakata, Risa Yoshiyuki, Ryoki Okada, Sohta Urushidani, Naoki Tarutani, Kiyofumi Katagiri, Kei Inumaru, Kyohei Koyama, Yuji Masubuchi
Summary: A facile method using urea as a nitriding agent was developed to prepare strontium-tantalum perovskite oxynitride and its solid solutions, providing environmentally benign alternatives to conventional inorganic pigments. The use of sol-gel-derived Ta2O5 gel allowed for faster nitridation at lower temperatures compared to conventional processes, while optimization of reaction conditions enabled the production of solid solutions with easily adjustable optical properties. The narrower band gaps of oxynitrides compared to oxides led to optical absorption and chromatic colors in the products.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Yu Zhang, Yuan Yuan, Jie Cai, Hao Dong, Xin Zhou
Summary: Sr2Nb2O7 and Sr2Ta2O7 with layered perovskite structures are capable of photocatalytic water splitting in the ultraviolet region, which can be enhanced by loading NiO as a cocatalyst. Density functional theory calculations reveal that NiO strongly adsorbs on the semiconductor surfaces of Sr2M2O7 (010) (M = Nb and Ta). NiO acts as the active site for the water oxidation reaction, facilitating the transfer of photoinduced holes from the surface. The formation of interfacial structures between NiO and Sr2M2O7 (010) surfaces has minimal influence on the absorption edge, and H2O tends to molecularly adsorb on the bare surfaces.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Tomoki Kanazawa, Shunta Nishioka, Shuhei Yasuda, Daichi Kato, Toshiyuki Yokoi, Shunsuke Nozawa, Hiroshi Kageyama, Kazuhiko Maeda
Summary: The local structure dependence of BaTiO3-xHx on the doped H- amount was investigated using Raman and X-ray absorption fine-structure (XAFS) spectroscopy measurements. It was found that the tetragonal phase transforms into the cubic phase when the doped H- amount is relatively large (x ≥ 0.2). XAFS measurements revealed that the TiO6 octahedral symmetry in BaTiO3-xHx is strongly affected by the doped H- amount, where an increase of H- relaxes the local distortion of the Ti [111] displacement and causes the tetragonal-to-cubic structural change.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Jie Meng, Zhenyun Lan, Weihua Lin, Mingli Liang, Xianshao Zou, Qian Zhao, Huifang Geng, Ivano E. Castelli, Sophie E. Canton, Tonu Pullerits, Kaibo Zheng
Summary: By combining experimental and theoretical methods, we investigate the hot carrier relaxation dynamics in Mn-doped lead halide perovskite nanocrystals. We find that Mn2+ doping enhances the electron-LO phonon coupling and introduces new relaxation pathways, leading to accelerated cooling of high-temperature hot carriers when excited above the bandgap. This phenomenon is advantageous for the energy conversion process in hot carrier solar cells.
Article
Geochemistry & Geophysics
Toshimori Sekine, Tsubasa Tobase, Youjun Zhang, Ginga Kitahara, Akira Yoshiasa, Tomoko Sato, Takamichi Kobayashi, Akihisa Mori
Summary: Heavy meteorite impacts on Earth’s surface produce natural glasses called tektites and impact glasses with various shapes and characteristics. Their formation conditions have been debated, and they are important in understanding planetary formation and evolution. By conducting experiments on a tektite, researchers found that shock compression and post-shock annealing affect the density and structure of the glass, but the local structures around titanium ions remain unchanged. The presence of different valance states of titanium ions in the glass provides insights into the formation conditions of impact-derived glasses.
AMERICAN MINERALOGIST
(2023)
Article
Materials Science, Multidisciplinary
Chenchen Shi, Yue Liu, Biao Wang, Bingbing Niu, Chunling Lu
Summary: The use of identical anode and cathode materials in symmetrical solid oxide fuel cells (SSOFCs) can reduce costs and prolong operational life. In this study, Nb-doped double perovskite Sr2CoFeO6 was employed as the electrode material for SSOFCs, which improved electrochemical performance and reversibility. The Nb-doped sample Sr2CoFe0.7Nb0.3O6 exhibited good chemical compatibility with SOFC electrolytes and demonstrated fuel-flexible characteristics.
Article
Multidisciplinary Sciences
Jack E. N. Swallow, Michael W. Fraser, Nis-Julian H. Kneusels, Jodie F. Charlton, Christopher G. Sole, Conor M. E. Phelan, Erik Bjorklund, Peter Bencok, Carlos Escudero, Virginia Perez-Dieste, Clare P. Grey, Rebecca J. Nicholls, Robert S. Weatherup
Summary: Operando soft X-ray absorption spectroscopy is used to study the chemical evolution of the solid electrolyte interphase (SEI) on the anodes of Li-ion batteries during electrochemical formation. The results reveal the sequential formation of inorganic and organic components of the SEI, and the role of fluoroethylene carbonate (FEC) in enhancing SEI formation and improving cycling performance. This technique provides new insights into the formation mechanisms and stability of electrode-electrolyte interphases for different electrode materials and electrolyte formulations.
NATURE COMMUNICATIONS
(2022)
Article
Green & Sustainable Science & Technology
Gengshu You, Le Liu, Jin Wang, Min Zhao, Chengjie Zhao, Xu Cai, Jin Tang, Fushen Lu, Tonggang Jiu
Summary: Polythiophene-acid-based conjugated polyelectrolytes have shown promising potential as hole-transport materials for inverted planar perovskite devices. A simple and effective strategy involving tris(pentafluorophenyl)borane as a Lewis acid has been developed to regulate the aggregation of the polyelectrolytes, leading to improved efficiency of perovskite solar cells.
ADVANCED SUSTAINABLE SYSTEMS
(2021)
Article
Materials Science, Ceramics
Takuya Sakata, Risa Yoshiyuki, Sohta Urushidani, Naoki Tarutani, Kiyofumi Katagiri, Kei Inumaru
Summary: The use of Ta-Ti binary oxide gel helps in developing single-phase solid solutions with homogeneous atomic distribution; utilizing urea as a nitriding agent eliminates harmful ammonia gas; the color of solid solutions depends on band gap and Ti reduction state, resulting in various chromatic colors.
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Physical
Tihana Cizmar, Ivana Panzic, Ivana Capan, Andreja Gajovic
Summary: The study investigated the role of Cu(II) ions in Cu-modified immobilized nanostructured TiO2 photocatalysts, showing that Cu(II) cations can reduce the recombination rate of photo generated charge carriers and improve the photocatalytic activity.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Hiroyuki Asakura, Seiji Yamazoe, Teppei Misumi, Aki Fujita, Tatsuya Tsukuda, Tsunehiro Tanaka
RADIATION PHYSICS AND CHEMISTRY
(2020)
Article
Chemistry, Multidisciplinary
Wataru Kurashige, Yutaro Mori, Shuhei Ozaki, Masanobu Kawachi, Sakiat Hossain, Tokuhisa Kawawaki, Cameron J. Shearer, Akihide Iwase, Gregory F. Metha, Seiji Yamazoe, Akihiko Kudo, Yuichi Negishi
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2020)
Article
Chemistry, Physical
Chikako Yanagisawa, Seiji Yamazoe, Yusuke Sunada
Summary: A planar tetranuclear palladium cluster was synthesized from the reaction of a cyclotetrasilane with [Pd((CNBu)-Bu-t)(2)](3), exhibiting efficient catalytic activity for the hydrogenation of alkenes and alkynes. Single-crystal X-ray diffraction analysis and DFT calculations revealed that the tetranuclear framework was effectively supported by the bridging organosilylene ligand.
Article
Chemistry, Multidisciplinary
Shu Fujita, Sho Yamaguchi, Jun Yamasaki, Kiyotaka Nakajima, Seiji Yamazoe, Tomoo Mizugaki, Takato Mitsudome
Summary: Alloying non-noble metal nanoparticles with phosphorus is a promising strategy for developing smart catalysts with high activity and air stability. For example, the novel nano-Ni2P catalyst exhibits excellent hydrogenation performance in water and can be easily reused without pretreatment.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Tomoki Matsuyama, Jun Hirayama, Yu Fujiki, Soichi Kikkawa, Wataru Kurashige, Hiroyuki Asakura, Naomi Kawamura, Yuichi Negishi, Naoki Nakatani, Keisuke Hatada, Fukiko Ota, Seiji Yamazoe
Summary: The electronic states of gold clusters are significantly influenced by different ligands, as observed through X-ray absorption spectroscopy. Differences in white-line intensity and peak positions were found between phosphine- and thiolate-protected gold clusters.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Hiroya Ishikawa, Min Sheng, Ayako Nakata, Kiyotaka Nakajima, Seiji Yamazoe, Jun Yamasaki, Sho Yamaguchi, Tomoo Mizugaki, Takato Mitsudome
Summary: In this study, a supported cobalt phosphide nanoalloy catalyst was developed for the selective hydrogenation of furfural derivatives, showing high efficiency and air stability without the need for H-2 pretreatment. Backdonation from Co d-electrons to the pi* orbital of furfural derivatives was found to play a key role in the highly efficient hydrogenation process.
Article
Chemistry, Inorganic & Nuclear
Naoya Haraguchi, Tomoki Okunaga, Yuto Shimoyama, Naoki Ogiwara, Soichi Kikkawa, Seiji Yamazoe, Miki Inada, Takashi Tachikawa, Sayaka Uchida
Summary: In this study, a redox-active ionic crystal based on a Dawson-type polyoxometalate was utilized to form and stabilize small mixed-valence luminescent silver clusters without the aid of protecting ligands at room temperature. Through ion-exchange and electron-transfer reactions, silver ions were introduced to form mixed-valence luminescent clusters, which were found to exist in a tetrahedral geometry based on photoluminescence and X-ray absorption fine structure analysis.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Mizuki Ishimaru, Fumiaki Amano, Chiho Akamoto, Seiji Yamazoe
Summary: This study investigated the reaction conditions of Pd-loaded Ga2O3 photocatalysts for enhanced production of ethane and hydrogen, revealing the crucial role of water vapor in promoting the photocatalytic non-oxidative coupling of methane. The presence of water vapor was found to significantly increase the production rate of C2H6 and H-2, with an apparent quantum efficiency of 5.1% under certain conditions. Water adsorbates on the photocatalyst surface were suggested to play a key role in facilitating the dehydrogenative coupling of CH4.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Applied
Hisao Yoshida, Akira Yamamoto, Saburo Hosokawa, Seiji Yamazoe, Soichi Kikkawa, Kenji Hara, Mitsutaka Nakamura, Kazuya Kamazawa, Tsunehiro Tanaka
Summary: The study reveals that the adsorbed hydrogen species on catalyst surfaces exhibit different properties depending on the precious metals and support materials. In situ inelastic neutron scattering spectroscopy allows for direct and selective observation of these species, providing valuable insights into catalytic processes.
TOPICS IN CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Sho Yamaguchi, Shu Fujita, Kiyotaka Nakajima, Seiji Yamazoe, Jun Yamasaki, Tomoo Mizugaki, Takato Mitsudome
Summary: A nickel phosphide nanoalloy supported by hydrotalcite demonstrated high catalytic activity for the hydrogenation of maltose, leading to efficient production of maltitol. Cooperative catalysis by the nanoalloy and the support played a key role in this process, enabling high-yield production even at ambient temperature. The catalyst showed promising performance in concentrated maltose solutions, highlighting its potential for sustainable production of maltitol.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Multidisciplinary Sciences
Shu Fujita, Kohei Imagawa, Sho Yamaguchi, Jun Yamasaki, Seiji Yamazoe, Tomoo Mizugaki, Takato Mitsudome
Summary: A novel cerium dioxide-supported nickel phosphide nanoalloy (nano-Ni2P/CeO2) was found to efficiently catalyze the C-3 alkylation of oxindoles with alcohols through borrowing hydrogen methodology. The catalyst showed high catalytic activity comparable to precious metal-based catalysts and could be easily recovered and reused without significant loss of activity, demonstrating cooperative catalysis between the Ni2P nanoalloy and CeO2 support.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Multidisciplinary
Tomoaki Takayama, Rio Kariya, Yuki Nakaya, Shinya Furukawa, Seiji Yamazoe, Takayuki Komatsu
Summary: Nanoparticulate intermetallic compound Ni3Ga supported on SiO2 is a highly efficient catalyst for the hydrosilylation of carbonyls, such as aldehydes and ketones, at room temperature. The key to the catalytic performance lies in the formation of electron-enriched Ni through alloying with Ga.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Sho Yamaguchi, Shu Fujita, Kiyotaka Nakajima, Seiji Yamazoe, Jun Yamasaki, Tomoo Mizugaki, Takato Mitsudome
Summary: The study presents a non-noble metal catalyst, nickel phosphide nanoparticle supported on hydrotalcite, which effectively catalyzes the selective hydrogenation of d-glucose to d-sorbitol in water, with high yield and over 99% selectivity under mild conditions. This nano-Ni2P/HT catalyst shows superior activity compared to other non-noble metal catalysts, can operate at ambient temperature under just 1 bar of H-2, and is stable and reusable, providing a cheap, green, and sustainable route for the production of d-sorbitol.
Article
Chemistry, Physical
Seiji Yamazoe, Akira Yamamoto, Saburo Hosokawa, Ryoichi Fukuda, Kenji Hara, Mitsutaka Nakamura, Kazuya Kamazawa, Tatsuya Tsukuda, Hisao Yoshida, Tsunehiro Tanaka
Summary: This study successfully identified various H species on the Pt/Al2O3 catalyst surface using in situ techniques and theoretical calculations. Different H species were found to play different active roles in the C2H4 hydrogenation reaction, and Al2O3 itself can also act as a hydrogen storage material.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Polymer Science
Ryo Nishimura, Yohei Hattori, Masako Akazawa, Jun-ichiro Kitai, Shinichiro Okude, Yuki Sakamoto, Seiji Yamazoe, Satoshi Yokojima, Shinichiro Nakamura, Kingo Uchida
Summary: The study analyzed the products and reaction mechanism of the polymerization reaction of 2-bromo-3-methoxythiophene through various techniques. A side reaction of the autopolymerization reaction was found and the polymerization reaction mechanism was estimated to occur in multiple steps. Hydrogen bromide gas acted as a catalyst and acid in the polymerization reaction when using brominated alkoxythiophene as a monomer.
