Copper Photodeposition on TiO2 Studied with HREM and EXAFS

Abstract

The possibility of direct selective surface activation by photodeposition of autocatalytic Cu particles on photosensitiveTiO2 substrates in an alkaline electroless copper solution has been investigated. The nucleation and growth of particleswere characterized by transmission electron microscopy (TEM). Ex situ high resolution TEM and in situ extendedx-ray absorption fine structure (EXAFS) spectroscopy were used to determine the oxidation state of photodeposited particleson thin polycrystalline TiO2 films and suspended TiO2 powders, respectively. It is shown that in the initial stages ofphotodeposition small (