Alex T Kuvarega
University of South Africa, South Africa
Title: Nitrogen, platinum group metal co-doped TiO2 for photocatalytic organic pollutants removal from water
Biography
Biography: Alex T Kuvarega
Abstract
The photocatalytic performance of a number of non-metal, metal co-doped TiO2 for the degradation of a dye under simulated solar radiation was investigated. The synthesised materials were characterised by FTIR, Raman Spectroscopy, XRD, DRUV-Vis, SEM and TEM. The N, metal co-doped TiO2 containing 0.5 wt.% of the metal consisted mainly of the anatase phase, with a particle size range of 15 - 28 nm. The TiO2 particles were largely spherical with some showing metal clusters dispersed on their surfaces. Co-doping shifted the material absorption edge well into the visible region. Band gap reduction was more pronounced for the N, PGM co-doped TiO2 compared to N, base metal co-doped samples. Co-doping led to an enhancement in the photocatalytic activity of the materials for the degradation of eosin yellow. N, Pd co-doped TiO2 was the most effective photocatalyst (99.9% dye removal) while N, Cu co-doped TiO2 showed the least activity (25.5% dye removal). The mechanism for the photocatalytic enhancement was proposed on the basis of formation of an electron deficient Schottky barrier at the semiconductor-metal interface, which act as an electron sink and thus retards electron-hole recombination. It was shown that the ability of the photocatalyst to degrade the dye depends on the nature and type of the metal dopant in co-doped TiO2 system.