Synthesis of highly dispersed platinum nanoparticles on Ti-containing mesoporous silica using photo-assisted deposition.
A simple and unique route to synthesize the nano-size Pt particles using mesoporous silica support including single-site Ti-oxide moiety (Ti-HMS) under UV-light irradiation has been developed. By the photo-assisted deposition (PAD) method, a Pt precursor can be deposited from aqueous solution of H2PtCl6 directly on the photo-excited isolated Ti-oxide moiety. The subsequent reduction with H2 generates the nano-sized Pt metal particles (PAD-Pt/Ti-HMS). The deposition of Pt precursor onto the Ti-HMS can be recognized by the observation of the decrease in the intensity of the preedge in the Ti K-edge XANES spectrum, demonstrating that the Pt precursor underwent anchoring on the single framework Ti4+ center of Ti-HMS under UV-light irradiation. The lower intensity of the Pt-Pt bond of the PAD-Pt/Ti-HMS than that of Pt foil in the Fourier transforms of Pt L(III)-edge EXAFS spectra clearly suggests the formation of the Pt nanoparticles. The PAD-Pt/Ti-HMS exhibited the higher catalytic activity for the hydrogenation of nitrobenzene to aniline and the NO reduction than the catalyst prepared by the conventional impregnation.
Shironita
Sayoko
S
Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
Mori
Kohsuke
K
Ohmichi
Tetsutaro
T
Taguchi
Eiji
E
Mori
Hirotaro
H
Yamashita
Hiromi
H