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Tsuda, Yasutaka; Gueriba, J. S.*; Ueta, Hirokazu*; Dio, W. A.*; Kurahashi, Mitsunori*; Okada, Michio*
JACS Au (Internet), 2(8), p.1839 - 1847, 2022/08
Takakuwa, Yuji*; Ogawa, Shuichi*; Yoshigoe, Akitaka
Hoshako, 35(3), p.158 - 171, 2022/05
Ambient pressure X-ray photoelectron spectroscopy for in situ observation of surface reactions using high-brightness synchrotron radiation shows a rapid progress in the number of endstations since about 2005 and is applied to various practical research field for clarifying reactions at solid/gas interfaces of e.g. catalyst, solid/liquid interfaces of e.g. fuel cell, and gas/liquid interfaces of e.g. ion liquid. In this review, a history of the development of APXPS, real-time observation of the surface reactions for Si chemical vapor deposition and Si dry oxidation, issues of APXPS, and future prospects are described.
Katsube, Daiki*; Ono, Shinya*; Takayanagi, Shuhei*; Ojima, Shoki*; Maeda, Motoyasu*; Origuchi, Naoki*; Ogawa, Arata*; Ikeda, Natsuki*; Aoyagi, Yoshihide*; Kabutoya, Yuito*; et al.
Langmuir, 37(42), p.12313 - 12317, 2021/10
Times Cited Count:1 Percentile:6.77(Chemistry, Multidisciplinary)We investigated the oxidation of oxygen vacancies at the surface of anatase TiO(001) using supersonic seeded molecular beam (SSMB) of oxygen. The oxygen vacancies at the top-surface and sub-surface could be eliminated by the supply of oxygen using an SSMB. These results indicate that the interstitial vacancies can be mostly assigned to oxygen vacancies, which can be effectively eliminated by using an oxygen SSMB. Oxygen vacancies are present on the surface of anatase TiO(001) when it is untreated before transfer to a vacuum chamber. These vacancies, which are stable in the as-grown condition, could also be effectively eliminated using the oxygen SSMB.
Ogawa, Shuichi*; Taga, Ryo*; Yoshigoe, Akitaka; Takakuwa, Yuji*
Journal of Vacuum Science and Technology A, 39(4), p.043207_1 - 043207_9, 2021/07
Times Cited Count:1 Percentile:7.86(Materials Science, Coatings & Films)Nickel (Ni) is used as a catalyst for nitric oxide decomposition and ammonia production but it is easily oxidized and deactivated. Clarification of the reduction process of oxidized Ni is essential to promote more efficient use of Ni catalysts. In this study, the reduction processes were investigated by in situ time-resolved photoelectron spectroscopy. We propose a two-step reduction reaction model. The rate-limiting process for the first step is surface precipitation of O atoms and that of the second step is dissociation of H molecules.
Kusaka, Ryoji; Kumagai, Yuta; Yomogida, Takumi; Takano, Masahide; Watanabe, Masayuki; Sasaki, Takayuki*; Akiyama, Daisuke*; Sato, Nobuaki*; Kirishima, Akira*
Journal of Nuclear Science and Technology, 58(6), p.629 - 634, 2021/06
Times Cited Count:7 Percentile:66.68(Nuclear Science & Technology)Ogawa, Shuichi*; Zhang, B.*; Yoshigoe, Akitaka; Takakuwa, Yuji*
Vacuum and Surface Science, 64(5), p.218 - 223, 2021/05
The oxidation reaction kinetics on Ti(0001) and Ni(111) surfaces were observed by real-time photoelectron spectroscopy using synchrotron radiation to measure the oxidation state and oxide thickness. After the Ti(0001) surface was wholly covered by TiO with a thickness of 1.2 nm, the rapid growth of n-type TiO proceeded through the diffusion of Ti ions to the TiO surface at 400C. A saturation of oxygen uptake on the TiO surface indicates that the O sticking coefficient on the TiO surface is negligibly small and the segregation of Ti to the TiO surface is a trigger to initiate the TiO growth. On the Ni(111) surface at 350C, a thermally stable NiO proceeded preferentially and then the growth of p-type NiO was initiated. The time evolution of NiO thickness was represented by a logarithmic growth model, where the NiO growth is governed by the electron tunneling to the NiO surface.
Yoshigoe, Akitaka
Hoshako, 32(4), p.185 - 198, 2019/07
Synchrotron radiation photoelectron spectroscopy is a beneficial technique for precise analysis of chemical states of solid surfaces. Owing to its high luminosity, it ensures availability of termed synchrotron radiation real-time photoelectron spectroscopy which enables "" observation of chemical reactions with gas molecules occurring at surfaces. In this review, oxygen adsorption reactions in the oxidation of silicon single crystal surfaces are focused. Through the demonstration of our research, the usefulness of synchrotron radiation real-time photoelectron spectroscopy to study molecular adsorption reactions at solid surfaces is briefly described and the future perspective would also be shown.
Yoshigoe, Akitaka
X-sen Kodenshi Bunkoho, p.271 - 282, 2018/12
Based on the series of author's studies, the author explains the time-resolved synchrotron radiation X-ray photoelectron spectroscopy and supersonic oxygen molecular beam study on the adsorption reaction dynamics of oxygen molecules at the Si single crystal surface in the section 5.10 of the new textbook "X-ray Photoelectron Spectroscopy" (Kodan-sha) edited by Yuji Takakuwa.
Igarashi, Shinichi*; Itakura, Akiko*; Kitajima, Masahiro*; Nakano, Shinsuke*; Muto, Shunsuke*; Tanabe, Tetsuo*; Yamamoto, Hiroyuki; Hojo, Kiichi
Hyomen Kagaku, 25(9), p.562 - 567, 2004/09
Surface stress can be utilized positively in modifying the surface reaction potential and increasing the surface reactivity. Blister is a local protrusion of solid surface induced by gas ion irradiation, and is considered to create local stress on surface layers. Si(100) substrate was irradiated with 10 keV H (fluence; 110 ions/m) at an angle of 30 to the surface normal. The blisters of several m in diameter at the bottom were formed. After the ion irradiation, the substrate was oxidized. By means of scanning Auger microscopy, we observed that the rims of the blisters have higher oxygen intensities than the flat surfaces and the tops have lower than the flats. The calculated stress distribution of the blister shows that the surface layers should be stretched laterally at the top of blisters and are compressed at the rim, relative to the flat surfaces. The O distribution clearly consists with the stress distribution of the surface. Our results demonstrate a patterned oxidation of Si surface applying its reactivity depending on the surface stress.
Nakazawa, Tetsuya; Yokoyama, Keiichi; Grismanovs, V.*; Katano, Yoshio*; Jitsukawa, Shiro
Journal of Nuclear Materials, 307-311(Part2), p.1436 - 1440, 2002/12
Times Cited Count:1 Percentile:10.15(Materials Science, Multidisciplinary)no abstracts in English
Yoshigoe, Akitaka; Teraoka, Yuden
Applied Surface Science, 190(1-4), p.60 - 65, 2002/05
Times Cited Count:10 Percentile:47.94(Chemistry, Physical)no abstracts in English
Nakazawa, Tetsuya; Yokoyama, Keiichi; Grismanovs, V.*; Katano, Yoshio*; Jitsukawa, Shiro
Journal of Nuclear Materials, 302(2-3), p.165 - 174, 2002/04
Times Cited Count:3 Percentile:23.41(Materials Science, Multidisciplinary)no abstracts in English
Urisu, Tsuneo*; Kitajima, Masahiro*; Teraoka, Yuden
Oyo Butsuri, 71(1), p.114 - 115, 2002/01
no abstracts in English
Nakazawa, Tetsuya; Yokoyama, Keiichi; Grismanovs, V.*; Katano, Yoshio*
Journal of Nuclear Materials, 297(1), p.69 - 76, 2001/07
Times Cited Count:9 Percentile:56.08(Materials Science, Multidisciplinary)no abstracts in English
Teraoka, Yuden; Yoshigoe, Akitaka
JAERI-Tech 2001-006, 91 Pages, 2001/03
no abstracts in English
Teraoka, Yuden; Yoshigoe, Akitaka; Sano, Mutsumi*
JAERI-Tech 2000-080, 33 Pages, 2001/02
no abstracts in English
Teraoka, Yuden; Yoshigoe, Akitaka
Applied Surface Science, 169-170, p.738 - 741, 2001/01
Times Cited Count:67 Percentile:91.86(Chemistry, Physical)no abstracts in English
Saburi, Tei; Ogawa, Hiroaki; Ueda, Satoshi*; Kiuchi, Kiyoshi
JAERI-Tech 2000-057, 23 Pages, 2000/10
no abstracts in English
Arthur, R. C,*; Savage, D.*; Sasamoto, Hiroshi; Shibata, Masahiro; Yui, Mikazu
JNC TN8400 2000-005, 61 Pages, 2000/01
Kinetic data, including rate constants, reaction orders and activation energies, are compiled for 34 hydrolysis reactions involving feldspars, sheet silicates, zeolites, oxides, pyroxenes and amphiboles, and for similar reactions involving calcite and pyrite. The data are compatible with a rate law consistent with surface reaction control and transition-state theoly, which is incorporated in the geochemieal software package EQ3/6 and GWB. Kinetic data for the reactions noted above are strictly compatible with the transition-state rate law only under far-from-equilibrium conditions. It is possiblethat the data are conceptually consistent with this rate law under both far-from-equilibrium and near-to-equilibrium conditions, but this should be confirmed whenever possible through analysis of original experimental results, Due to limitations in the availability of kinetic data for mineral-water reactions, and in order to simplify evaluations of geochemical models of groundwater evolution, it is convenient to assume local-equilibrium in such models whenever possible. To assess whether this assumption is reasonable, a modeling approach accounting for coupled fluid flow and water-rock interaction is described that can be used to estimate spatial and temporal scale of local equiliblium. The approach is demonstrated for conditions involving groundwater flow in fractures at JNC's Kamaishi in-situ tests site, and is also used to estimate the travel time necessary for oxidizing surface waters to migrate to the level of a HLW repository in crystalline rock. The question of whether local equilibrium is a reasonable assumption must be addressed using an appropriate modeling approach. To be appropriate for conditions at the Kamaishi site using the modeling approach noted above, the fracture fill must closely approximate a porous medium, groundwater flow must be purely advective and diffusion of solutes across the fracture-host rock boundary must not occur. Moreover, the ...
Teraoka, Yuden; Yoshigoe, Akitaka
Atomic Collision Research in Japan, No.25, p.97 - 98, 1999/00
no abstracts in English