PHOTOASSISTED DEGRADATION OF N-BUTYLTIN CHLORIDES IN AIR-EQUILIBRATEDAQUEOUS TIO2 SUSPENSION

The photoassisted degradation of n-butyltin chlorides in air-equilibra ted aqueous TiO2 suspension has been studied. Several factors affectin g the degradation rate, such as the extent of adsorption on the surfac e of catalyst particles and the effect of pH values, were examined. Pa rticular interest is focused on the TiO2-assisted photodegradation of n-butyltin species. The simultaneous photodeposition of tin oxides/met allic tin on the TiO2 surfaces is also addressed as a route to form su rface-complexed semiconductors. A mechanism consisting of interfacial trapping of a photogenerated electron-hole pair can explain the observ ed photoassisted degradation of n-butyltin species and the simultaneou s photodeposition of tin onto the TiO2 surface. The results are compar ed with those, previously reported, on the photolytic degradation of t hese species in water.