Nano-sized metal particles (Pt and Pd) can be fabricated under UV-light irradiation using a photo-assisted deposition (PAD-SP) method on the single-site photocatalyst. The nano-sized metals were deposited directly on the photo-excited tetrahedrally coordinated titanium oxide moieties within the frameworks. Characterization by X-Ray Absorption Fine Structure (XAFS) and Transmission Electron Microscope (TEM) analysis revealed that the size of metal particles depends on the preparation methods and that the metal particles with the smaller size were formed on the photo-deposited catalysts compared to the conventionally prepared impregnated catalysts. These nano-sized metal catalysts are useful as efficient catalysts for the various reactions such as the oxidation of CO and the direct synthesis of H2O2 from H2 and O2 under an aqueous condition. The direct interaction between the precusor species of the nano-sized metal and the photo-excited tetra-titanium-oxide realized by the PAD-SP method has possibility to design the unique and active nano-sized metal catalysts.
