Catalysis of nanosized Pd metal catalyst deposited on Ti-containing zeolite by a photo-assisted deposition (PAD) method*
Hiromi Yamashita1, Yuki Miura1, Kohsuke Mori1, Sayoko Shironita1, Yosuke Masui1, Naoki Mimura1, Tetsutaro Ohmichi1, Takao Sakata2, and Hirotaro Mori2
1Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; 2Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
Abstract: Using a photo-assisted deposition (PAD) method, nanosized Pd metal can be highly dispersed on Ti-containing silicalite zeolite (TS-1) under UV-light irradiation (PAD-Pd/TS-1). The nanosized Pd metal was deposited directly on the photo-excited tetrahedrally coordinated titanium oxide species (tetra-Ti-oxide) of TS-1 zeolite. Under the flow of H2 and O2 in water solvent, the efficient formation of H2O2 could be observed by the PAD-Pd/TS-1 catalyst under mild reaction conditions (ambient temperature and atmospheric pressure). Furthermore, the presence of phenol in this reaction system led to the formation of the products from the partial oxidation of phenol with the formed H2O2.
Keywords: nano Pd metal; photo-assisted deposition; single-site photocatalysts; zeolites.
*Pure Appl. Chem. 79, 1831-2100. An issue of reviews and research papers based on lectures presented at the 1st International IUPAC Conference on Green-Sustainable Chemistry, held in Dresden, Germany, 10-15 September 2006.