Surface study of organopalladium molecules on S-terminated GaAs

硫黄終端したGaAs上の有機パラジウム分子についての表面研究

小西 智也*; 西脇 永敏*; 東條 孝志*; 石川 琢馬*; 寺岡 輝記*; 植田 有紀子*; 木原 義文*; 森時 秀司*; 遠野 竜翁*; 武藏 美緒*; 多田 孝*; 藤川 誠司; 高橋 正光; Bell, G.*; 下田 正彦*; 塚本 史郎*

Konishi, Tomoya*; Nishiwaki, Nagatoshi*; Tojo, Takashi*; Ishikawa, Takuma*; Teraoka, Teruki*; Ueta, Yukiko*; Kihara, Yoshifumi*; Moritoki, Hideji*; Tono, Tatsuo*; Musashi, Mio*; Tada, Takashi*; Fujikawa, Seiji; Takahashi, Masamitsu; Bell, G.*; Shimoda, Masahiko*; Tsukamoto, Shiro*

Organopalladium species (Pd) immobilized on an Sterminated GaAs substrate (S/GaAs) effectively catalyzes C-C bond formation in the Mizoroki-Heck reaction with cycle durability. However, the immobilizing mechanism of Pd is unknown. In this study, we deposited Pd(OCOCH) on S/GaAs in two different methods, namely dry-physical vapor-deposition and wetchemical deposition, and compared the catalytic activities in the Mizoroki-Heck reaction. Also, S-termination and Pd-immobilization on GaAs grains were performed by the wet-chemical method to monitor the change in the surface chemical structure during the preparation process with diffuse reflectance Fourier transform infrared spectroscopy (FT-IR). FT-IR measurements implied that the immobilization of catalytic active was related to the OH groups on the S-terminated surface. Pd-S/GaAs prepared dryphysically showed poor catalytic activity, because Pd was not immobilized under absence of OH groups.