Synthesis, structure and photocatalytic activity of nano $TiO_{2}$ and nano $Ti_{1-x}M_{x}O{2-delta}$ (M = Cu, Fe, Pt, Pd, V, W, Ce, Zr)

摘要

We have synthesized 5-7 nm size, highly crystalline $TiO_{2}$ which absorbs radiation in the visible region of solar spectrum. The material shows higher photocatalytic activity both in UV and visible region of the solar radiation compared to commercial Degussa P25 $TiO_{2}$. Transition metal ion substitution for $Ti^{4+}$ creates mid-gap, states which act as recombination centers for electron-hole induced by photons thus reducing photocatalytic activity. However, Pt, Pd and Cu ion substituted $TiO_{2}$ are excellent CO oxidation and NO reduction catalysts at temperatures less than 100 degrees C.