Photodeposition of Metal and Metal Oxide at the TiOx Nanosheet to Observe the Photocatalytic Active Site

Photodeposition of Ag, Cu, Cu 2 O, and MnO 2 at a TiO x nanosheet with a lepidocrocite-type structure prepared from K 0.8 Ti 1.73 Li 0.27 O 4 was carried out to observe the active sites for the photocatalytic reaction during UV illumination. Photodepositions of Ag, Cu, and Cu 2 O, that is, photoreduction, occurred mainly at edges in the lateral direction of the nanosheet, indicating that the photoproduced electron moves in the network of Ti 4+ ions in the nanosheet. On the other hand, photodeposition of MnO 2, that is, photooxidation, occurred on all over the surface of the nanosheet, indicating that the photoproduced hole exists at the O 2− ion of the nanosheet surface.