Clay Supported Anisotropic Au Modified N,S doped TiO2 Nanoparticles for Enhanced Photocatalytic Dye Degradation, Esterification Reactions
Visible light active photocatalysts are very much important towards environmental sustainability. A clay supported anisotropic Au nanoparticles deposited N,S-doped TiO2 plasmonic photocatalyst has been developed. Successful deposition of ~10 nm TiO2 nanoparticles was carried out using sol-gel method and then ~40 nm Au NPs by oxalic acid reduction on kaolinite clay. The role of Au NPs was to generate more excitons by the photocatalyst in its vicinity, the photocatalytic degradation rate constant was increased by 82% in its presence. The photocatalyst was further modified by co-doping of N and S to reduce the band-gap to make it more efficient in visible light. A 9-fold increase in degradation rate constant was observed for doped samples. The degradation rate constant was further increased by 28% in the presence of an electrolyte (Na2HPO4) because of enhancement of dye adsorption capacity on the clay surface. The photocatalytic esterification of oleic acid to methyl oleate was increased 10-fold compared to that of un-doped one.