PiFM and XPS Studies of Porous TiO2 Films for the Photocatalytic Decomposition of Polystyrene

The rate of photocatalytic oxidation polystyrene over 0.1 wt% copper-doped TiO2 catalyst spin coated onto a flat substrate is investigated as function the deposition speed and, hence, film thickness. Photoinduced force microscopy and photoelectron spectroscopy show no evidence any products remaining on surface after reaction. reaction shows discernible dependence speed; it close to zero order in concentration exhibits ½ life almost 50 times greater than equivalent stearic acid same catalysts. No difference between decay aliphatic aromatic hydrogens polymer was observed, suggesting that once chain begins oxidising, subsequent steps are relatively rapid. This consistent with rate-determining step being dependent extent coordination surface, which much more favourable because its carboxylic group.