研究者データベース

三輪 寛子(ミワ ヒロコ)
触媒科学研究所 触媒表面研究部門
助教

基本情報

所属

  • 触媒科学研究所 触媒表面研究部門

職名

  • 助教

学位

  • 博士(理学)(東京大学)

J-Global ID

研究キーワード

  • 触媒   水素   TiO2   ミュオン   酸素欠陥   表面科学   酸化物表面   AFM   金ナノクラスター   PTRF-XAFS   TPRF-XAFS   電気化学   二酸化チタン   STM   ナノクラスター   金クラスター   

研究分野

  • ナノテク・材料 / 機能物性化学
  • ナノテク・材料 / 基礎物理化学

職歴

  • 2010年 - 2015年 北海道大学 触媒化学研究センター 助教

学歴

  •         - 2008年   東京大学   理学系研究科
  •         - 2008年   東京大学
  •         - 2005年   東京大学   理学系研究科
  •         - 2005年   東京大学
  •         - 2003年   東京大学   理学部
  •         - 2003年   東京大学

所属学協会

  • 触媒学会   日本化学会   表面科学会   

研究活動情報

論文

  • Barrow Elizabeth, Seuser Grant S, Ariga-Miwa Hiroko, Chen Donna A, Lauterbach Jochen, Asakura Kiyotaka
    SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 20 1 379 - 387 2019年12月31日 [査読有り][通常論文]
  • Kashaboina Upendar, Nishikawa Yuta, Wakisaka Yuki, Sirisit Natee, Nagamatsu Shin-ichi, Bao Deling, Ariga-Miwa Hiroko, Takakusagi Satoru, Inami Yuta, Kuriyama Fumiya, Dipu Arnoldus Lambertus, Ogihara Hitoshi, Iguchi Shoji, Yamanaka Ichiro, Wada Takahiro, Asakura Kiyotaka
    CHEMISTRY LETTERS 48 9 1145 - 1147 2019年09月 [査読有り][通常論文]
  • Yamada Yasuyuki, Sugiura Takuya, Morita Kentaro, Ariga-Miwa Hiroko, Tanaka Kentaro
    INORGANICA CHIMICA ACTA 489 160 - 163 2019年04月01日 [査読有り][通常論文]
  • Sirisit Natee, Kido Daiki, Wakisaka Yuki, Ariga-Miwa Hiroko, Takakusagi Satoru, Asakura Kiyotaka, Sekizawa Oki, Sakata Tomohiro, Uruga Tomoya, Iwasawa Yasuhiro
    E-JOURNAL OF SURFACE SCIENCE AND NANOTECHNOLOGY 16 387 - 390 2018年09月01日 [査読有り][通常論文]
  • Yuan Qiuyi, Wakisakai Yuki, Uemura Yohei, Wada Takahiro, Ariga-Miwa Hiroko, Takakusagi Satoru, Asakura Kiyotaka, Brankovic Stanko R
    JOURNAL OF PHYSICAL CHEMISTRY C 122 29 16664 - 16673 2018年07月26日 [査読有り][通常論文]
  • Contreras-Mora Jose, Ariga-Miwa Hiroko, Takakusagi Satoru, Williams Christopher T, Asakura Kiyotaka
    JOURNAL OF PHYSICAL CHEMISTRY C 122 11 6318 - 6322 2018年03月22日 [査読有り][通常論文]
  • Ma Tao, Ariga Hiroko, Takakusagi Satoru, Asakura Kiyotaka
    THIN SOLID FILMS 646 12 - 16 2018年01月31日 [査読有り][通常論文]
  • Takashi Toyao, S. M. A. H. Siddiki, Yoshitsugu Morita, Takashi Kamachi, Abeda S. Touchy, Wataru Onodera, Kenichi Kon, Shinya Furukawa, Hiroko Ariga, Kiyotaka Asakura, Kazunari Yoshizawa, Ken-ichi Shimizu
    CHEMISTRY-A EUROPEAN JOURNAL 23 59 14848 - 14859 2017年10月 [査読有り][通常論文]
     
    Herein, we report a heterogeneous TiO2-supported Re catalyst (Re/TiO2) that promotes various selective hydrogenation reactions, which includes the hydrogenation of esters to alcohols, the hydrogenation of amides to amines, and the N-methylation of amines, by using H-2 and CO2. Initially, Re/TiO2 was evaluated in the context of the selective hydrogenation of 3-phenylpropionic acid methyl ester to afford 3-phenylpropanol (p(H2)=5 MPa, T=180 degrees C), which revealed a superior performance over other catalysts that we tested in this study. In contrast to other typical heterogeneous catalysts, hydrogenation reactions with Re/TiO2 did not produce dearomatized byproducts. DFT studies suggested that the high selectivity for the formation of alcohols in favor of the hydrogenation of aromatic rings is ascribed to the higher affinity of Re towards the COOCH3 group than to the benzene ring. Moreover, Re/TiO2 showed a wide substrate scope for the hydrogenation reaction (19 examples). Subsequently, this Re/TiO2 catalyst was applied to the hydrogenation of amides, the N-methylation of amines, and the N-alkylation of amines with carboxylic acids or esters.
  • Hua Huang, Takahiro Wada, Hiroko Ariga, Satoru Takakusagi, Kiyotaka Asakura, Yasuhiro Iwasawa
    CHEMICAL PHYSICS LETTERS 683 18 - 21 2017年09月 [査読有り][通常論文]
     
    High-performance catalysts are often composed of two or more active phases, which are believed to interact with each other at the mesoscopic scale structure. Unlike conventional powder catalysts flat surfaces is advantageous in that its surface structure can be precisely designed. We prepared precisely designed Sb2O4/VSbO4/Si catalysts containing Sb2O4 ribbons with finely controlled width and separation by electron lithography. We demonstrated that the acrolein generation rate on the catalysts was related to the width and separation of the Sb2O4 ribbons. This work shows the possibility to regulate catalyses by inhomogeneity of the surface structure at the mesoscopic level. (C) 2017 Elsevier B.V. All rights reserved.
  • Qiuyi Yuan, Satoru Takakusagi, Yuki Wakisaka, Yohei Uemura, Takahiro Wada, Hiroko Ariga, Kiyotaka Asakura
    CHEMISTRY LETTERS 46 8 1250 - 1253 2017年08月 [査読有り][通常論文]
     
    We studied the initial stage of a Pt monolayer produced by surface-limited redox replacement (SLRR) using polarization-dependent total reflection fluorescence X-ray absorption fine structure (PTRF-XAFS). Different from the widely accepted understanding that metallic monolayer islands are formed, our XAFS showed that the Pt monolayer, initially present on the Au(111) substrate, was mainly in the form of a planar [PtCl4](2-) complex with its molecular plane parallel to Au(111). This result provides a new insight into the mechanism of SLRR.
  • Promotional Effect of Water on Direct Dimethyl Ether Synthesis from Carbon Monoxide and Hydrogen Catalyzed by Cu−Zn/Al2O3
    Kaoru Takeishi, Yutaro Wagatsuma, Hiroko Ariga, Kenichi Kon, Ken-ichi Shimizu
    ACS Sustainable Chemistry & Engineering 5 3675 - 3680 2017年03月 [査読有り][通常論文]
  • Satoru Takakusagi, Akitoshi Kunimoto, Natee Sirisit, Hiromitsu Uehara, Tadashi Ohba, Yohei Uemuara, Takahiro Wada, Hiroko Ariga, Wang-Jae Chun, Yasuhiro Iwasawa, Kiyotaka Asakura
    JOURNAL OF PHYSICAL CHEMISTRY C 120 29 15785 - 15791 2016年07月 [査読有り][通常論文]
     
    Ni and Pt structures evaporated onto a TiO2(110) surface premodified with ortho-mercaptobenzoic acid (o-MBA) were studied using polarization-dependent total reflection fluorescence X-ray absorption fine structure analysis to determine the effects of the premodification on the dispersion of the metal atoms over the TiO2(110) surface. Ni was found to be atomically dispersed with the formation of S-Ni-O bonds (where the S is provided by the o-MBA and the 0 is present in the TiO2 lattice) on the surface. In contrast, Pt underwent aggregation to form small clusters. The varying behavior of these metals on the o-MBA-modified TiO2(110) surface is discussed based on the energy difference between sulfur-metal-oxygen and metal-metal bond formations, and we propose a new indicator for single metal dispersion on the TiO2(110) surface.
  • Takahiro Kaito, Hiroyuki Tanaka, Hisashi Mitsumoto, Seiho Sugawara, Kazuhiko Shinohara, Hiroko Ariga, Hiromitsu Uehara, Satoru Takakusagi, Kiyotaka Asakura
    JOURNAL OF PHYSICAL CHEMISTRY C 120 21 11519 - 11527 2016年06月 [査読有り][通常論文]
     
    In order to examine the relationship between the oxygen reduction reaction (ORR) activity of a fuel cell catalyst and its structure and/or electronic state, carbon-supported Pt and Pt alloys having various structures, compositions, and morphologies were studied. Regardless of the atomic ordering or morphology (core-shell or random alloy) of the catalyst, the ORR activity was primarily dependent on the Pt-Pt bond distance. Among these materials, Pt2Co, having the shortest Pt-Pt distance, exhibited the highest ORR activity. The activities of this catalyst per unit surface. area and per unit mass were approximately 10 times and 6 times higher than those of a commercially available carbon supported Pt electrocatalyst (Pt/C). This work also found a monotonic increase in catalytic activity with decreasing Pt-Pt distance.
  • I. Mochizuki, H. Ariga, Y. Fukaya, K. Wada, M. Maekawa, A. Kawasuso, T. Shidara, K. Asakura, T. Hyodo
    PHYSICAL CHEMISTRY CHEMICAL PHYSICS 18 10 7085 - 7092 2016年03月 [査読有り][通常論文]
     
    The exact structure of the rutile-TiO2(110)-(1 x 2) surface, which had been under debate over the past 30 years, was investigated using the newly developed technique of total-reflection high-energy positron diffraction (TRHEPD), which is a positron counterpart of reflection high-energy electron diffraction (RHEED). The rocking-curves for the 00-spot obtained from the experimental diffraction patterns were compared to the curves for various models calculated with a full-dynamical theory. It was found that the rocking-curves matched those for a surface consisting of a Ti2O3 configuration, originally suggested by Onishi and Iwasawa [H. Onishi and Y. Iwasawa, Surf. Sci., 1994, 313, L783], but with a further modification of atomic positions close to the ones proposed by Wang et al. [Q. Wang, A. R. Oganov, Q. Zhu and X. F. Zhou, Phys. Rev. Lett., 2014, 113, 266101]. This result demonstrates that TRHEPD can distinguish between the existence and absence of the oxygen atoms on the topmost surface, and between the Ti atoms residing in positions at the interstitial-vertical sites and those at interstitial-horizontal sites.
  • Tao Ma, Kotaro Miyazaki, Hiroko Ariga, Satoru Takakusagi, Kiyotaka Asakura
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 88 8 1029 - 1035 2015年08月 [査読有り][通常論文]
     
    The cleanliness of transferred graphene is of significant importance for its application as the window material in environmental cells used for electron microscopy and spectroscopy. We investigated the dependence of the cleanliness of graphene on transfer routes, including FeCl3 etching, (NH4)(2)S2O8 etching, electrochemical delamination, and O(2-)bubbling, by means of transmission electron microscopy and X-ray photoelectron spectroscopy. It was found that electrochemical delamination provided the cleanest graphene with only a small amount of poly(methyl methacrylate) (PMMA) residue existing on the surface.
  • Zhenxin Zhang, Toru Murayama, Masahiro Sadakane, Hiroko Ariga, Nobuhiro Yasuda, Norihito Sakaguchi, Kiyotaka Asakura, Wataru Ueda
    NATURE COMMUNICATIONS 6 2015年07月 [査読有り][通常論文]
     
    The development of metal oxide-based molecular wires is important for fundamental research and potential practical applications. However, examples of these materials are rare. Here we report an all-inorganic transition metal oxide molecular wire prepared by disassembly of larger crystals. The wires are comprised of molybdenum(VI) with either tellurium(IV) or selenium(IV): {(NH4)(2)[XMo6O21]}(n) (X = tellurium(IV) or selenium(IV)). The ultrathin molecular nanowires with widths of 1.2 nm grow to micrometre-scale crystals and are characterized by single-crystal X-ray analysis, Rietveld analysis, scanning electron microscopy, X-ray photoelectron spectroscopy, ultraviolet-visible spectroscopy, thermal analysis and elemental analysis. The crystals can be disassembled into individual molecular wires through cation exchange and subsequent ultrasound treatment, as visualized by atomic force microscopy and transmission electron microscopy. The ultrathin molecular wire-based material exhibits high activity as an acid catalyst, and the band gap of the molecular wire-based crystal is tunable by heat treatment.
  • F. Mauriello, H. Ariga, M. G. Musolino, R. Pietropaolo, S. Takakusagi, K. Asakura
    APPLIED CATALYSIS B-ENVIRONMENTAL 166 121 - 131 2015年05月 [査読有り][通常論文]
     
    The transfer hydrogenolysis of glycerol promoted by supported palladium catalysts is reported. The reactions were carried out under mild conditions (453K and 5 bar of N-2) in absence of added hydrogen by using the reaction solvent, 2-propanol, as hydrogen source. The catalytic results are interpreted in terms of metal (Pd)-metal (Co or Fe) interaction that modifies the electronic properties of palladium and affords bimetallic PdM sites (M= Co or Fe), thus enhancing the catalytic properties of the systems in the conversion of glycerol as well as in the selectivity to 1,2-propanediol and 1-propanol. The transfer hydrogenolysis mechanism is here elucidated and involves the glycerol dehydration to 1-hydroxyacetone and the subsequent hydrogenation of 1-hydroxyacetone to propylene glycol. (C) 2014 Elsevier B.V. All rights reserved.
  • Qiuyi Yuan, Hiroko Ariga, Kiyotaka Asakura
    TOPICS IN CATALYSIS 58 4-6 194 - 200 2015年04月 [査読有り][通常論文]
     
    Ni2P has demonstrated high catalytic activity for hydrodesulfurization and has recently been employed as a catalyst in a variety of other reactions. We have thoroughly reviewed the literature concerning Ni2P single crystal surfaces, with the aim of determining the relationship between surface structure and catalytic properties. Published results to date indicate that Ni2P single crystal surfaces exhibit reconstructed structures, and so the bulk terminated structure may not be stable. We have also reviewed the surface structures and electronic states of (1 x 1) and reconstructed Ni2P(0001) and (). Based on these reviews, this paper presents general rules regarding stabilization of the Ni2P surface structure and discusses the role of phosphorus in the single crystal surfaces.
  • Naoyoshi Murata, Makoto Kobayashi, Yukari Okada, Takuya Suzuki, Hiroaki Nitani, Yasuhiro Niwa, Hitoshi Abe, Takahiro Wada, Shingo Mukai, Hiromitsu Uehara, Hiroko Ariga, Satoru Takakusagi, Kiyotaka Asakura
    REVIEW OF SCIENTIFIC INSTRUMENTS 86 3 034102  2015年03月 [査読有り][通常論文]
     
    We present the design and performance of a high-temperature in situ cell with a large solid angle for fluorescence X-ray absorption fine structure (XAFS) spectra. The cell has a large fluorescence XAFS window (116 mm(phi)) near the sample in the cell, realizing a large half-cone angle of 56 degrees. We use a small heater (25 x 35 mm(2)) to heat the sample locally to 873 K. We measured a Pt-SnO2 thin layer on a Si substrate at reaction conditions having a high activity. In situ measurement enables the analysis of the difference XAFS spectra between before and during the reaction to reveal the structure change during the operation. (C) 2015 AIP Publishing LLC.
  • Satoru Takakusagi, Takafumi Ogawa, Hiromitsu Uehara, Hiroko Ariga, Ken-ichi Shimizu, Kiyotaka Asakura
    CHEMISTRY LETTERS 43 11 1797 - 1799 2014年11月 [査読無し][通常論文]
     
    Pt was successfully electrodeposited on a Nb-doped TiO2(110) electrode from a solution of 1 mM K-2[PtCl4] and 50 mM H2SO4 using single-pulse chronoamperometry. The morphology of the deposited Pt nanoparticles was sensitive to the deposition potential and holding time. A novel method for the preparation of metal particles on a single-crystal TiO2 surface in a controlled manner has been proposed.
  • Takahiro Kaito, Hisashi Mitsumoto, Seiho Sugawara, Kazuhiko Shinohara, Hiromitsu Uehara, Hiroko Ariga, Satoru Takakusagi, Kiyotaka Asakura
    REVIEW OF SCIENTIFIC INSTRUMENTS 85 8 084104  2014年08月 [査読有り][通常論文]
     
    A new spectroelectrochemical cell to investigate the structure of Pt/Au nanoclusters using Pt and Au K-edge X-ray absorption fine structure (XAFS) measurements under the electrochemical conditions is developed. K-edge XAFS measurements for Pt and Au require a sample as thick as 1-2 cm, which prevents homogeneous potential distribution. We can measure in situ Pt and Au K-edge XAFS spectra and determine reasonable electrochemical surface areas using our developed spectroelectrochemical cell. This work provides a new approach to analyze Pt/Au core-shell nanoclusters. The new cell is designed to be applied to both spectra with high absorption-edge energies such as the K-edge of Pt and Au and those with low absorption-edge energy such as Pt L-edge. (C) 2014 AIP Publishing LLC.
  • Keisuke Fujikawa, Hiroko Ariga, Satoru Takakusagi, Hiromitsu Uehara, Tadashi Ohba, Kiyotaka Asakura
    e-Journal of Surface Science and Nanotechnology 12 322 - 329 2014年07月 [査読有り][通常論文]
     
    We have developed a new Reverse Monte Carlo code, called the micro Reverse Monte Carlo (m-RMC), which is applicable to structure analysis of nanomaterials and surface species. In the m-RMC, Reverse Monte Carlo is applied to an ensemble of replica files, each of which contains one molecule or one small cluster, because the Extended X-ray Absorption Fine Structure (EXAFS) is sensitive to short-range structures and has negligible interaction between molecules or clusters. We apply the m-RMC to face-centered cubic metals (Cu, Pd, and Pt) and discuss the advantages, validation, and problems of the m-RMC. The bond distance and some cumulant coefficients can be determined from the EXAFS using m-RMC. Some 50-100 replica files are sufficient to reproduce the EXAFS oscillations and radial distributions. The bond distance can be determined, including the asymmetric distributions, by m-RMC. We also apply m-RMC to α-MoO 3 and Au clusters. The m-RMC analysis of MoO3 shows that three radial distribution peaks appear corresponding to three types of Mo-O bonds. The m-RMC analysis of Au cluster indicates the presence of Au 55 cuboctahedral structure with Au-Au distance at 0.288 nm. We obtain a 3 D image of Au55 nanocluster from the unified file. The m-RMC method can be applied to the analysis of the EXAFS for chemical systems with appropriate care. © 2014 The Surface Science Society of Japan.
  • Xinlei Zheng, Haiqiang Lin, Jianwei Zheng, Hiroko Ariga, Kiyotaka Asakura, Youzhu Yuan
    TOPICS IN CATALYSIS 57 10-13 1015 - 1025 2014年06月 [査読無し][通常論文]
     
    Cu/SBA-15 catalysts containing a small amount of Pt (Cu-Pt/SBA-15) were prepared by sequential adsorption-reduction method and examined for chemoselective hydrogenation of dimethyl oxalate(DMO) to ethylene glycol (EG). The Cu-Pt/SBA-15 catalyst with an optimal Cu/Pt atomic ratio of 10 showed a DMO conversion close to 100 % with a 98 % selectivity to EG at a temperature as low as 463 K. The results showed that the best Cu-Pt/SBA-15 enhanced the space time yield of EG by about 1.47 times compared with Cu/SBA-15. The introduction of Pt with stronger ability for H-2 adsorption and activation substantially enhanced the reducibility of the Cu2+ species and further promoted the chemisorption capacity of H-2. After reduction, a portion of Cu was alloyed with Pt, which was beneficial for the generation and stabilization of a balanced Cu+/Cu-0 ratio during the hydrogenation process.
  • Takahiro Kaito, Hisashi Mitsumoto, Seiho Sugawara, Kazuhiko Shinohara, Hiromitsu Uehara, Hiroko Ariga, Satoru Takakusagi, Yoshikiyo Hatakeyama, Keiko Nishikawa, Kiyotaka Asakura
    JOURNAL OF PHYSICAL CHEMISTRY C 118 16 8481 - 8490 2014年04月 [査読無し][通常論文]
     
    A carbon-supported Pt-shell Au-core electrocatalyst (Pt/Au/C) was prepared by sequential deposition of Pt ions on the surface of Au nanoparticles supported on carbon. The area-specific activity of the oxygen reduction reaction (ORR) for the prepared Pt/Au/C in 0.1 M HClO4, aqueous solution was approximately 2 times higher than that for a commercial carbon-supported Pt electrocatalyst (Pt/C). The core-shell structure was confirmed using electrochemical methods and Pt and Au K-edge X-ray absorption fine structure (XAFS) analysis. XAFS analyses indicated that the Pt-Pt bond distance for the Pt/Au/C catalyst was shorter than that for Pt foil and the Pt/C catalyst. In addition, the Au Au distance was much shorter than that for Au foil. The reason for the high ORR activity of Pt/Au/C is considered to be shorter Pt-Pt bond distance as compared to that of Pt/C.
  • Hirosuke Matsui, Fumihiko Matsui, Naoyuki Maejima, Hiroshi Daimon, Tomohiro Matsushita, Hiroko Ariga, Kiyotaka Asakura
    e-Journal of Surface Science and Nanotechnology 12 53 - 56 2014年02月20日 [査読無し][通常論文]
     
    The surface alloying is the important topics in Ni2P study which is expected for next generation hydrodesulfurization and hydrodenitrogenation catalyst. The atomic structure and catalytic properties of a single crystalline Ni2P surface modified with W (W-Ni2P) was investigated by photoelectron diffraction (PED) and spectroscopy. PED is an element and site selective surface structure analysis method that enables observation of three-dimensional atomic configurations of the surface local structure. The selective replacement of W to the Ni site in the Ni2P crystal was clarified by PED. Chemical reactivities for NO molecules of the W-Ni 2P and the clean Ni2P surfaces were compared. On the clean Ni2P surface, the NO adsorption did not occur, whereas W-Ni 2P surface showed remarkable activity for NO adsorption. © 2014 The Surface Science Society of Japan.
  • Wenjing Li, Linmin Ye, Pei Long, Jin Chen, Hiroko Ariga, Kiyotaka Asakura, Youzhu Yuan
    RSC ADVANCES 4 55 29072 - 29082 2014年 [査読無し][通常論文]
     
    Supported bimetallic Ru-Fe catalysts were prepared using a step-deposition-reduction method. The selective hydrogenolysis of acetic acid to ethanol was investigated as a reaction, which is considered to be related to the transformation of biomass-derived carboxylic acids to fuels and value-added chemicals. An SBA-15-supported Ru-Fe catalyst displayed significant improvements in catalytic performance for the hydrogenolysis of acetic acid to ethanol compared with monometallic catalysts and that with SiO2 as a carrier. When the Ru/Fe atomic ratio was set at 2/1, the prepared catalyst could give a nearly 100% conversion of acetic acid and 88% selectivity to ethanol. The catalyst showed considerable stability in terms of structure and performance for a long-term run on stream. Characterization results indicated that a small portion of Fe species was alloyed with Ru, whereas the other portion of Fe species, likely FeO1+x (0 < x < 0.5), was dispersed on the catalyst surfaces. The Fe species were crucial for the stabilization of Ru-Fe bimetallic nanoparticles and activation of acetic acid molecules in the hydrogenolysis reaction. Moreover, several other carboxylic acids, such as propionic acid, levulinic acid, and lactic acid, could also be efficiently converted to their corresponding alcoholic chemicals or lactone using the optimized Ru-Fe/SBA-15 catalyst under relatively mild conditions.
  • Hiroko Ariga, Mayumi Kawashima, Satoru Takakusagi, Kiyotaka Asakura
    CHEMISTRY LETTERS 42 12 1481 - 1483 2013年12月 [査読無し][通常論文]
     
    The electronic and structural properties of a phosphorus-terminated structure of Ni2P(0001) surface (Ni3PP) are investigated by density functional theory (DFT) calculations. Phosphorus adsorption largely stabilizes the Ni2P(0001) surface by creating Ni-P bonds on the Ni trimer. Atomic hydrogen can adsorb on the topmost P site although its adsorption energy is much lower than its adsorption energy on the Ni trimer site of the Ni3P2 surface. Our results suggest that the Ni trimer is the key factor for high catalytic activity.
  • Ying Huang, Hiroko Ariga, Xinlei Zheng, Xinping Duan, Satoru Takakusagi, Kiyotaka Asakura, Youzhu Yuan
    Journal of Catalysis 307 74 - 83 2013年08月13日 [査読無し][通常論文]
     
    We present the application of a one-step urea-assisted gelation method to prepare a SiO2-supported bimetallic catalyst composed of copper (Cu) and silver (Ag). Results show the remarkably enhanced performance of the catalyst for selective hydrogenation of dimethyl oxalate (DMO) to ethylene glycol (EG). Coupled with a series of characterization and kinetic studies, the improved activity is attributed to the formation of Cu nanoparticles containing Ag nanoclusters on the SiO2 surface. The coherent interactions between the Cu and Ag species help create the active Cu+/Cu 0 species in a suitable proportion and prevent the transmigration of bimetallic nanoparticles during the hydrogenation process. The optimized CuAg/SiO2 catalyst with an Ag/Cu atomic ratio of 0.05 has a balanced Cu+/Cu0 ratio and highly dispersed bimetal particles, which account for its high turnover frequency, EG selectivity of 97.0%, and excellent catalytic stability during the hydrogenation of DMO to EG for longer than 150 h. © 2013 Elsevier Inc. All rights reserved.
  • Hiromitsu Uehara, Muhammad Haneef Bin Hanaffi, Yuichiro Koike, Keisuke Fujikawa, Shushi Suzuki, Hiroko Ariga, Satoru Takakusagi, Wang-Jae Chun, Yasuhiro Iwasawa, Kiyotaka Asakura
    CHEMICAL PHYSICS LETTERS 570 64 - 69 2013年05月 [査読無し][通常論文]
     
    The structures of Ni clusters formed on a highly-stepped TiO2(110) surface were studied by polarization-dependent total reflection fluorescence X-ray absorption fine structure analysis. When 0.8 monolayers of Ni were deposited, three-dimensional Ni clusters with 1-2 nm diameters and heights less than 1 nm were formed. Conversely, when 0.07 monolayers of Ni were deposited, an anisotropic Ni trimer with a Ni-Ni distance of 0.260 nm was created at the [001] step. We revealed that the surface modification to enhance the metal-anion interaction can control the deposited metal structure. (C) 2013 Elsevier B.V. All rights reserved.
  • Satoru Takakusagi, Hirotaka Nojima, Hiroko Ariga, Hiromitsu Uehara, Kotaro Miyazaki, Wang-Jae Chun, Yasuhiro Iwasawa, Kiyotaka Asakura
    PHYSICAL CHEMISTRY CHEMICAL PHYSICS 15 33 14080 - 14088 2013年 [査読有り][通常論文]
     
    Three-dimensional structures of vacuum-deposited Cu species formed on TiO2(110) surfaces premodified with three mercaptobenzoic acid (MBA) isomers were studied using polarization-dependent total reflection fluorescence X-ray absorption fine structure (PTRF-XAFS). We explored the possibility of fine tuning and orientation control of the surface Cu structures, including their coordination and configuration against the surface, according to the different mercapto group positions of the three MBA isomers (o(-), m(-), and p-MBA). Almost linear S-Cu-O (lattice O of TiO2) surface compounds were formed on the three MBA-modified TiO2(110) surfaces; however, the orientation of the Cu species on the o- and m-MBA-modified TiO2(110) surfaces (40-45 degrees inclined from the surface normal) was different from that on the p-MBA-modified TiO2(110) surface (60 degrees from the surface normal). This work suggests that the selection of a different MBA isomer for premodification of a single crystal TiO2(110) surface enables fine tuning and orientation control of surface Cu complexes.
  • Kiyotaka Asakura, Satoru Takakusagi, Hiroko Ariga, Wang-Jae Chun, Shushi Suzuki, Yuichiro Koike, Hiromitsu Uehara, Kotaro Miyazaki, Yasuhiro Iwasawa
    FARADAY DISCUSSIONS 162 165 - 177 2013年 [査読有り][通常論文]
     
    Three-dimensional Au structures on bare and organic-compound-modified TiO2(110) surfaces were interrogated by Au L-3-edge polarization dependent total reflection fluorescence X-ray absorption fine structure (PTRF-XAFS) spectroscopy. On the bare TiO2(110) surface, icosahedral Au-55 nanoclusters were the main product found. When the surfaces were modified with ortho or meso mercaptobenzoic acid (o-MBA or m-MBA), Au was atomically dispersed. Sulfur atoms in the o- and m-MBA formed strong covalent bonds with Au to produce stable Au-MBA (o-and m-forms) surface complexes. On the other hand, only oxygen atoms on the surface did not make a strong enough interaction to stabilize the Au species. We discuss how the Au species formed on the modified TiO2(110) surface and the possibility to control the Au structure by the surface modification method.
  • Hui-Feng Wang, Hiroko Ariga, Rhys Dowler, Martin Sterrer, Hans-Joachim Freund
    JOURNAL OF CATALYSIS 286 1 - 5 2012年02月 [査読無し][通常論文]
     
    In this work, we introduce a surface science approach to supported metal catalyst preparation utilizing thin, single-crystalline oxide films as substrates. The use of thin oxide films allows for combined morphological and chemical characterization of the sample at various steps of a typical catalyst preparation procedure. A Fe3O4-supported Pd model catalyst was prepared by impregnation of (FeO4)-O-3(1 1 1) films with acidic PdCl2 solution, and the transformation of the adsorbed precursor into supported Pd nanoparticles by stepwise heating in vacuum was followed with scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). The results provide evidence for homogeneous nucleation of Pd particles out of a monolayer of adsorbed precursor and an enhancement of the particle-support interaction with increasing annealing temperature. Chlorine, which remains on the model catalyst surface after vacuum annealing, could be removed by oxidation/reduction. This treatment also leads to particle sintering with an increase in the average particle diameter from 2 nm to 4 nm after oxidation/reduction. (C) 2011 Elsevier Inc. All rights reserved.
  • Changbin Zhang, Fudong Liu, Yanping Zhai, Hiroko Ariga, Nan Yi, Yongchun Liu, Kiyotaka Asakura, Maria Flytzani-Stephanopoulos, Hong He
    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION 51 38 9628 - 9632 2012年 [査読有り][通常論文]
  • Ya-nan Wang, Xinping Duan, Jianwei Zheng, Haiqiang Lin, Youzhu Yuan, Hiroko Ariga, Satoru Takakusagi, Kiyotaka Asakura
    CATALYSIS SCIENCE & TECHNOLOGY 2 8 1637 - 1639 2012年 [査読無し][通常論文]
     
    The performance of an SBA-15-supported Cu catalyst for hydrogenation of dimethyl oxalate to ethylene glycol is markedly promoted with Au. A key genesis of the high activity of the catalyst is ascribed to the formation of Cu-Au alloy nanoparticles which stabilize the active species and retard their agglomeration during the hydrogenation process.
  • Bodong Li, Juan Wang, Youzhu Yuan, Hiroko Ariga, Satoru Takakusagi, Kiyotaka Asakura
    ACS CATALYSIS 1 11 1521 - 1528 2011年11月 [査読有り][通常論文]
     
    Carbon nanotube-supported RuFe bimetallic catalysts (RuFe/CNT) were prepared through a coimpregnation method for the selective hydrogenolysis of 20 wt % glycerol aqueous solution to produce glycols (1,2-propanediol and ethylene glycol). The Ru/CNT catalyst with smaller Ru nanoparticles (NPs) was significantly active for C-C bond cleavage, giving a considerable amount of CH(4) in the hydrogenolysis product. The RuFe/CNT catalyst with bimetallic NPs having an average size similar to Ru/CNT was more efficient for C-O bond cleavage, affording higher selectivity to glycols. Almost 100% glycerol conversion and over 75% selectivity to glycol could be obtained using the optimized RuFe/CNT catalyst under relatively mild conditions. The bimetallic RuFe/CNT catalyst was structurally robust and showed excellent reusability. Transmission electron microscopic images revealed that, when an appropriate amount of Fe entity was added, the RuFe bimetallic NPs were uniformly dispersed on the CNT surfaces and had an average size of similar to 3 nm. X-ray photoelectron spectroscopy indicated that a portion of the Fe species were interacted with Ru moieties, forming Ru-Fe alloys on the Ru domain, whereas other Fe species were in the forms of iron oxides, likely FeO and FeO(1+x) (0 < x < 0.5), mostly presenting on the periphery of RuFe bimetallic NPs. The occurrence of iron oxide species is crucial for the stability of RuFe bimetallic NPs during catalytic runs; but excess iron oxides block the surfaces of RuFe bimetallic NPs, resulting in a decrease in catalytic activity. Higher performance of the RuFe/CNT catalyst is attributed to the synergistic effects of the formation of Ru-Fe alloys and the interactions between the RuFe bimetallic NPs and iron oxides on CNT surfaces.
  • Bodong Li, Juan Wang, Youzhu Yuan, Hiroko Ariga, Satoru Takakusagi, Kiyotaka Asakura
    ACS CATALYSIS 1 11 1521 - 1528 2011年11月 [査読無し][通常論文]
     
    Carbon nanotube-supported RuFe bimetallic catalysts (RuFe/CNT) were prepared through a coimpregnation method for the selective hydrogenolysis of 20 wt % glycerol aqueous solution to produce glycols (1,2-propanediol and ethylene glycol). The Ru/CNT catalyst with smaller Ru nanoparticles (NPs) was significantly active for C-C bond cleavage, giving a considerable amount of CH(4) in the hydrogenolysis product. The RuFe/CNT catalyst with bimetallic NPs having an average size similar to Ru/CNT was more efficient for C-O bond cleavage, affording higher selectivity to glycols. Almost 100% glycerol conversion and over 75% selectivity to glycol could be obtained using the optimized RuFe/CNT catalyst under relatively mild conditions. The bimetallic RuFe/CNT catalyst was structurally robust and showed excellent reusability. Transmission electron microscopic images revealed that, when an appropriate amount of Fe entity was added, the RuFe bimetallic NPs were uniformly dispersed on the CNT surfaces and had an average size of similar to 3 nm. X-ray photoelectron spectroscopy indicated that a portion of the Fe species were interacted with Ru moieties, forming Ru-Fe alloys on the Ru domain, whereas other Fe species were in the forms of iron oxides, likely FeO and FeO(1+x) (0 < x < 0.5), mostly presenting on the periphery of RuFe bimetallic NPs. The occurrence of iron oxide species is crucial for the stability of RuFe bimetallic NPs during catalytic runs; but excess iron oxides block the surfaces of RuFe bimetallic NPs, resulting in a decrease in catalytic activity. Higher performance of the RuFe/CNT catalyst is attributed to the synergistic effects of the formation of Ru-Fe alloys and the interactions between the RuFe bimetallic NPs and iron oxides on CNT surfaces.
  • Franziska Ringleb, Yuichi Fujimori, Hui-Feng Wang, Hiroko Ariga, Esther Carrasco, Martin Sterrer, Hans-Joachim Freund, Livia Giordano, Gianfranco Pacchioni, Jacek Goniakowski
    JOURNAL OF PHYSICAL CHEMISTRY C 115 39 19328 - 19335 2011年10月 [査読有り][通常論文]
     
    The structural and chemical properties of a monolayer FeO(111)/Pt(111) exposed to air, liquid water, and controlled atmospheres of water vapor and water vapor/oxygen mixtures have been studied by a combination of infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning tunneling microscopy experiments together with density functional calculations using ab initio thermodynamics. The FeO(111)/Pt(111) film is inert toward pure water vapor up to mbar pressure. Coadsorption of oxygen and water, however, transforms the film into a hydroxyl terminated trilayer with a (Pt-)O-Fe-OH structural motif. The trilayer film forms spontaneously upon contact of FeO(111)/Pt(111) with air and preserves long-range order even in liquid water. The calculated phase diagram in the relevant range of oxygen and water chemical potentials is in agreement with the experimental results and shows that the oxygen chemical potential is the main driving force for the formation of the trilayer film. Results for Au nucleation on and CO oxidation over the FeO(OH) film are presented and compared to previous studies on nonhydroxylated films.
  • Alvin B. Hernandez, Hiroko Ariga, Satoru Takakusagi, Kumiko Kinoshita, Shushi Suzuki, Shigeki Otani, S. Ted Oyama, Kiyotaka Asakura
    CHEMICAL PHYSICS LETTERS 513 1-3 48 - 52 2011年09月 [査読有り][通常論文]
     
    Nickel phosphide (Ni2P) is an emerging catalyst for hydrodesulfurization and other important environment- and energy-related catalytic reactions. To understand its high performance, the surface structure of a Ni2P (0 0 0 1) single crystal surface was investigated using dynamical LEED analysis. The obtained surface structure for Ni2P (0 0 0 1)-1 x 1 is a P-covered Ni3P2 structure (Ni3P_P structure) as opposed to the expected bulk terminated surface structures. This Letter discusses the driving force for the formation of the Ni3P_P surface, which involves the minimization of dangling bonds. (C) 2011 Elsevier B. V. All rights reserved.
  • Hui-Feng Wang, Hiroko Ariga, Rhys Dowler, Martin Sterrer, Hans-Joachim Freund
    Journal of Catalysis In Press  2011年 [査読有り][通常論文]
  • Donghui Guo, Yuta Nakagawa, Hiroko Ariga, Shushi Suzuki, Kumiko Kinoshita, Takeshi Miyamoto, Satoru Takakusagi, Kiyotaka Asakura, Shigeki Otani, S. Ted Oyama
    SURFACE SCIENCE 604 17-18 1347 - 1352 2010年08月 [査読有り][通常論文]
     
    The surface structure of Ni2P (10 (1) over bar0), a model for highly active hydrodesulfurization catalysts, was studied using scanning tunneling microscopy (STM) and low energy electron diffraction (LEED) in order to understand the reconstruction of the surface layers. Annealing at 573 K revealed a (1 x 1) LEED pattern which changed to a c(2 x 4) arrangement by further heating to 723 K. Atomic scale STM images were obtained for both the (1 x 1) and c(2 x 4) structures. Bright spots observed in the STM images were interpreted to be due to surface phosphorus atoms and this was supported by a density functional theory (INT) simulation. Several possible models for the c(2 x 4) reconstructed structures were proposed including a P-dimer defect model, a missing-row model and a missing-row + added-row model. The last model gave the best explanation for the c(2 x 4) structure. The mechanism for the c(2 x 4) reconstruction on the Ni2P (10 (1) over bar0) surface is discussed. (C) 2010 Elsevier B.V. All rights reserved.
  • Hiroko Ariga, Toshiaki Taniike, Harumo Morikawa, Mizuki Tada, Byoung Koun Min, Kazuya Watanabe, Yoshiyasu Matsumoto, Susumu Ikeda, Koichiro Saiki, Yasuhiro Iwasawa
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 131 41 14670 - + 2009年10月 [査読有り][通常論文]
     
    We used STM to observe visible tight photo-oxidation reactions of formic acid on the ordered lattice-work structure of a TiO2(001) surface for the first time. The nanostructured surface makes the band gap significantly smaller than 3.0 eV only at the surface layer, and the surface state of the crystal enables a visible light response.
  • H. Ariga, T. Taniike, H. Morikawa, R. Tero, H. Kondoh, Y. Iwasawa
    CHEMICAL PHYSICS LETTERS 454 4-6 350 - 354 2008年03月 [査読有り][通常論文]
     
    The lattice-work structure of a rutile TiO2(001) surface, which is faceted to {114} plane, was studied by combining scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption. ne structure (NEXAFS) and density functional theory (DFT) calculations. Synchrotron XPS and NEXAFS spectra taken for the faceted surface indicated that this surface possesses a stoichiometric composition. We propose a new stoichiometric structure model on the basis of XPS, NEXAFS, and atomically-resolved STM observations. DFT calculations revealed that the present stoichiometric model is energetically more favorable compared to the previously proposed models. (c) 2008 Elsevier B.V. All rights reserved.
  • H. Ariga, R. Tero, Y. Namai, Y. Iwasawa
    Microscopy and Microanalysis 10 482 - 483 2004年09月24日 [査読無し][通常論文]
  • STM study on photoreactions of adsorbed methanol and formic acid on a rutile TiO2(001) surface.
    H Ariga, R Tero, Y Namai, Y Iwasawa
    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 227 U1456 - U1456 2004年03月 [査読有り][通常論文]

講演・口頭発表等

  • μSR measurements of Photocatalyst rutile TiO2 single crystal  [通常講演]
    有賀 寛子
    The 2015 International Chemical Congress of Pacific Basin Societies (PACIFICHEM 2015) 2015年12月 ポスター発表
  • μSR measurements of rutile TiO2 single crystal: A new method to approach in Photocatalysis  [通常講演]
    有賀 寛子
    The 17th International Symposium on Relations between Homogeneous and Heterogeneous Catalysis (ISHHC17) 2015年07月 ポスター発表

その他活動・業績

受賞

  • 2005年 Student Poster Award

共同研究・競争的資金等の研究課題

  • 文部科学省:科学研究費補助金(若手研究(B))
    研究期間 : 2015年 -2016年 
    代表者 : 有賀 寛子
  • 文部科学省:科学研究費補助金(新学術領域研究(研究領域提案型))
    研究期間 : 2014年 -2015年 
    代表者 : 有賀 寛子
  • 文部科学省:科学研究費補助金(新学術領域研究(研究領域提案型))
    研究期間 : 2012年 -2013年 
    代表者 : 有賀 寛子
     
    本年度は,TiO2内に存在する酸素欠陥に捕捉されたmuonには,室温付近で電子を非常に弱く束縛した状態があることを見出した.Muonは水素様粒子として知られており,平均寿命2.2 μsで崩壊する時,主にスピン方向に陽電子を放出するため,崩壊直前のmuonのスピンの向きを観測することができる.そのため,外部磁場による摂動を加えることでmuonの電荷状態を知ることができる.このような性質を使い,触媒や光触媒内部での水素の分布や電荷分布を明らかにしていくことを,本研究の目的としている.我々は,まず,触媒担体や光触媒として広く用いられているTiO2内の水素,更に,欠陥構造内の水素の状態を明らかとすることとした.TiO2内の水素や欠陥構造内は,band gap内,もしくは,band gap付近にエネルギー準位を有するため,TiO2全体の物性や化学特性を大きく変化させることが知られており,これらを制御することが求められているが、電子状態の空間分布など基礎的なことがわかっていないのが現状である。そこで、muonをプローブとした測定を行った.試料は,構造の制御が比較的容易な単結晶基板を用いた.外部磁場(縦磁場、横磁場)を印加しながら,muonの回転を観測する(μSR法)ことで,酸素欠陥でmuonが安定化(準安定)すると,これまで考えられていなかった,muonに非常に弱く束縛された電子が室温付近で存在することがわかった.これは,酸素欠陥に水素が補足されると伝導帯に近いエネルギー準位を持つshallow stateを形成することを示唆している。欠陥と水素が導入されたTiO2は,特異な物性や光触媒能を示すことが近年報告されているが,本年度,新しく見出したstateが,これらの起源の一つである可能性が高い.このように、一つ一つの性質の起源を原子レベルで解明していくとこで,TiO2を始めとする,触媒や光触媒の機能の制御に繋がるものと考えられる。

大学運営

委員歴

  • 2012年   日本化学会   北海道支部役員   日本化学会


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