Nano-sized Pt particles with high activities for CO oxidation have been successfully synthesized on the metal dioxide phases (CeO(2) and TiO(2)) included within ZSM-5 zeolite by a photo-assisted deposition (PAD) method under UV-light irradiation The obtained Pt nanoparncles on CeO(2) within ZSM-5 by the PAD method (PAD-Pt/CeO(2)/ZSM-5) showed the highest catalytic activity for CO oxidation even at low temperature The dispersion of Pt nanoparncles was investigated by CO adsorption, XAFS, and TEM analyses The size of Pt nanoparticle of the PAD-Pt/CeO(2)/ZSM-5 catalyst was determined to be 2 nm In addition, this catalyst has unique morphology, the Pt nanoparncles were selectively deposited on the CeO(2) within ZSM-5 supports It is found that the addition of CeO(2) into the catalyst supports is effective to synthesize highly active nano-sized Pt particles using the PAD method under UV-light irradiation. (C) 2010 Elsevier B V All rights reserved