Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Kamiya, Junichiro; Takano, Kazuhiro*; Yuza, Hiromu*; Wada, Kaoru
e-Journal of Surface Science and Nanotechnology (Internet), 20(2), p.107 - 118, 2022/05
no abstracts in English
Yano, Masahiro; Uozumi, Yuki*; Yasuda, Satoshi; Asaoka, Hidehito; Tsukada, Chie*; Yoshida, Hikaru*; Yoshigoe, Akitaka
e-Journal of Surface Science and Nanotechnology (Internet), 16, p.370 - 374, 2018/08
Fukaya, Yuki
e-Journal of Surface Science and Nanotechnology (Internet), 16, p.111 - 114, 2018/04
no abstracts in English
Baba, Yuji; Shimoyama, Iwao
e-Journal of Surface Science and Nanotechnology (Internet), 16, p.53 - 59, 2018/03
Surface ionization for cesium chloride and Cs-adsorbed soil has been investigated. For cesium chloride, neutral cesium was desorbed around 645C which is close to the melting point of cesium. While Cs
ion was desorbed from 400
C. The ratio of desorbed ions and neutrals (Cs
/Cs
) has a maximum around 410
C. Temperature dependence of Cs
/Cs
was analyzed using Saha-Langmuir equation, As a result, it was found that the temperature maximum is due to the changes of the surface work function induced by the phase transition of CsCl.
Honda, Mitsunori; Shimoyama, Iwao; Baba, Yuji; Suzuki, Shinichi; Okamoto, Yoshihiro; Yaita, Tsuyoshi
e-Journal of Surface Science and Nanotechnology (Internet), 14, p.35 - 38, 2016/02
Matsumura, Daiju; Nishihata, Yasuo; Okajima, Yuka*
e-Journal of Surface Science and Nanotechnology (Internet), 14, p.48 - 52, 2016/00
Baba, Yuji; Shimoyama, Iwao; Hirao, Norie; Izumi, Toshinori
e-Journal of Surface Science and Nanotechnology (Internet), 13, p.417 - 421, 2015/09
Times Cited Count:1The interaction between alkali metals and oxides has attracted much attention as heterogeneous catalysis, chemical reaction promoters, and high intensity electron emitter. Also the interaction of cesium and oxides has become important subject, because radioactive cesium trapped in minerals such as clay and soil may cause health risks. In the present study, we analyzed chemical states of ultra-trace amount of cesium on oxide surfaces by total reflection X-ray photoelectron spectroscopy (TR-XPS) exited by synchrotron radiation. For the adsorbed cesium thicker than 0.01 layer, cesium is weakly bound with oxide through Van-der-Waals force. On the other hand, for ultra-thin layer about 0.002 layer, the chemical bond changes to covalent bond. It is suggested that this change in the chemical bonding state is one of the reasons why radioactive cesium is hard to be released from minerals.
Taguchi, Tomitsugu; Igawa, Naoki; Birumachi, Atsushi; Asaoka, Hidehito; Miwa, Shuhei; Osaka, Masahiko
e-Journal of Surface Science and Nanotechnology (Internet), 13, p.339 - 342, 2015/06
Rare-earth doped ceria exhibits both ionic and electronic conductions, and those ceria with higher ratio of ionic conduction against electronic conduction is used as a solid electrolyte for solid oxide fuel cells. The electron density distributions in crystals are closely related to the electron diffusing pathway which affects the electronic conduction. In this study, we investigated the electron density distribution of doped ceria as a function of the content of NdO
-dopant to deduce the ratio of the electronic to ionic conduction. The crystal structure was refined with the space group,
-3
, which is the same as undoped ceria. Ce and Nd ions randomly occupied the 4
site and O ion the 8
site. The electron conduction pathway was distributed through the 4
-8
and 8
-8
sites. The relationship between crystal structural change and electron density distribution as a function of the content of Nd
O
dopant will be discussed.
Igawa, Naoki; Kodama, Katsuaki; Birumachi, Atsushi; Taguchi, Tomitsugu
e-Journal of Surface Science and Nanotechnology (Internet), 13, p.247 - 252, 2015/05
The nuclear and electron density distributions of LiMnO
which is one of the primitive cathode materials for secondary Li-ion batteries, were analyzed by applying Rietveld refinement and MEM to neutron and X-ray diffraction data, to estimate the Li diffusing pathway. The crystal structure of LiMn
O
could be refined with the space group,
-3
in the temperature range from 240 to 573 K. The structure was transformed to
below 240 K. The isotropic thermal displacement parameter of Li was proportional to the temperature excluding 240 to 300 K. According to the MEM analyses it was indicated that the Li ions diffuse through 8
and 16
around 300 K.
Honda, Mitsunori; Yanagida, Masatoshi*; Han, L.*; Miyano, Kenjiro*
e-Journal of Surface Science and Nanotechnology (Internet), 12, p.63 - 67, 2014/02
Tang, J.*; Nishimoto, Kiwamu*; Ogawa, Shuichi*; Yoshigoe, Akitaka; Ishizuka, Shinji*; Watanabe, Daiki*; Teraoka, Yuden; Takakuwa, Yuji*
e-Journal of Surface Science and Nanotechnology (Internet), 11, p.116 - 121, 2013/11
Yokoyama, Yuta; Asaoka, Hidehito; Sinsarp, A.*; Sasaki, Masahiro*
e-Journal of Surface Science and Nanotechnology (Internet), 10, p.509 - 512, 2012/09
The Si(110) surface has a quite unique one-dimensional (1-D) structure with 162 reconstruction. Since the perfectly straight rows extend over micrometers, the 16
2 structure can be a superior template for 1-D nanostructures. In this study, we tried to control the clustering of Ge atoms on the Si(110) - 16
2 substrate. When Ge is deposited at 523 K, clustering of Ge atoms is found. The size of the cluster was 1
2 nm and many of them were located in a step edges. This trend is previously reported by vicinal Si(111) surface. With increasing temperature, the sizes of Ge clusters became larger. These results indicated that the size and alignment of the Ge cluster can be well controlled on the Si(110) - 16
2 template surface.
Fukaya, Yuki; Kubo, Keisuke*; Hirahara, Toru*; Yamazaki, Shiro*; Choi, W. H.*; Yeom, H. W.*; Kawasuso, Atsuo; Hasegawa, Shuji*; Matsuda, Iwao*
e-Journal of Surface Science and Nanotechnology (Internet), 10, p.310 - 314, 2012/07
no abstracts in English
Narita, Ayumi; Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Hirao, Norie; Yaita, Tsuyoshi
e-Journal of Surface Science and Nanotechnology (Internet), 10, p.367 - 373, 2012/07
To apply organic thin films as new devices, it is important to immobilize organic molecules on oxide surfaces. In this study, we investigated the formation of organic self-assembled monolayer on the oxide surface. Decyl phosphonic acid (DPA) molecules were used as the adsorbed molecule on the surface. The DPA film was prepared by immersing the sapphire substrate in DPA ethanol solution. The sample was measured by XPS using synchrotron soft X-ray. For the P 1s XPS spectra of the DPA powder and the DPA film on the sapphire surface, a single peak was observed and the binding energies of the two samples were almost the same. And we measured the sample by the total reflection (TR) XPS, which is highly surface sensitive method. Compared with the normal XPS, the intensity of the C 1s peak in TR-XPS was enhanced. As a result, it was elucidated that the phosphonic acid of the DPA molecule was located at the lower side, while the alkyl chain was located at the upper side on the surface.
Baba, Yuji; Narita, Ayumi; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Hirao, Norie; Entani, Shiro; Sakai, Seiji
e-Journal of Surface Science and Nanotechnology (Internet), 10, p.69 - 73, 2012/04
We report on the first results for the geometrical determination of adsorbed atoms on an oxide by a soft-X-ray sanding wave method. The samples investigated were alkyl phosphonic acid (C10) adsorbed on a sapphire surface, which is one of the candidate systems for organic self-assembled monolayer (SAM) on oxides. The surface was irradiated by synchrotron soft X-rays from the surface normal. The intensity of photoelectrons was plotted as a function of the photon energy. We observed clear profiles of the photoelectron intensity due to the standing wave from the substrate. Compared with the simulation using the crystal parameters, it was found that the phosphorus atoms are located at 0.11 nm from the surface, while the constant height was not observed for carbon atoms. The results are in consistent with the results by XPS and NEXAFS; the molecules form SAM on the sapphire surface with phosphonic acids and alkyl chains are located at the upper side.
Mimura, Kojiro*; Hosokawa, Shinya*; Happo, Naohisa*; Hu, W.; Hayashi, Koichi*; Wakita, Kazuki*; Ishii, Hirofumi*; Yoshimura, Masato*; Jeyakanthan, J.*; Mamedov, N.*
e-Journal of Surface Science and Nanotechnology (Internet), 9, p.273 - 276, 2011/07
Happo, Naohisa*; Tekehara, Yuki*; Fujiwara, Makoto*; Tanaka, Koichi*; Semba, Shinya*; Hosokawa, Shinya*; Hayashi, Koichi*; Hu, W.; Suzuki, Motohiro*; Asada, Hironori*
e-Journal of Surface Science and Nanotechnology (Internet), 9, p.247 - 250, 2011/06
Kasukabe, Yoshitaka*; Chen, Y.*; Yamamoto, Shunya; Yoshikawa, Masahito; Fujino, Yutaka*
e-Journal of Surface Science and Nanotechnology (Internet), 9, p.191 - 198, 2011/04
The purpose of this work is to study changes of the crystallographic and electronic structures of Ti films by heating and by nitriding during N-implantation into Ti films, using in-situ transmission electron microscope equipped with the instrument for electron energy loss spectroscopy, and then to clarify the atomistic nitriding processes of Ti thin films due to the N-implantation with the aid of self-consistent charge discrete variational X molecular orbital calculations. It is clarified that the maximum concentration of N in Ti films during the N-implantation and the change of electronic structures near the fermi level, respectively, depend on the implantation temperature and the ratio of N/Ti in Ti films. Furthermore, taking into account the bonding interaction of Ti sublattices with ligand N atoms, the transformation mechanisms between hcp-Ti and fcc-Ti sublattices due to the implantation of N atoms are discussed.
Fukaya, Yuki; Kawasuso, Atsuo; Ichimiya, Ayahiko*
e-Journal of Surface Science and Nanotechnology (Internet), 8, p.190 - 193, 2010/04
no abstracts in English
Hashimoto, Mie; Fukaya, Yuki; Kawasuso, Atsuo; Ichimiya, Ayahiko
e-Journal of Surface Science and Nanotechnology (Internet), 7, p.436 - 440, 2009/04
no abstracts in English