Enhancement in the Photocatalytic Activity of Au@TiO2 Nanocomposites by Pretreatment of TiO2 with UV LightBulletin of Korean Chemical Society (2012)
AbstractA novel, efficient and controlled protocol for the synthesis and enhanced photocatalytic activity of Au@TiO2 nanocomposite is developed. TiO2 (P25) was pretreated by employing UV light (λ = 254 nm) and the pretreated TiO2 was uniformly decorated by gold nanoparticles (AuNPs) in presence of sodium citrate and UV light. UV pretreatment makes the TiO2 activated, as electrons were accumulated within the TiO2 in the conduction band. These accumulated electrons facilitate the formation of AuNPs which were of very small size (2-5 nm), similar morphology and uniformly deposited at TiO2 surface. It leads to formation of stable and crystalline Au@TiO2 nanocomposites. The rapidity (13 hours), monodispersity, smaller nanocomposites and easy separation make this protocol highly significant in the area of nanocomposites syntheses. As-synthesized nanocomposites were characterized by TEM, HRTEM, TEM-EDX, SAED, XRD, UV-visible spectrophotometer and zeta potential. Dye degradation experiments of methyl orange show that type I (Au@TiO2 nanocomposites in which TiO2 was pretreated with UV light) has enhanced photocatalytic activity in comparison to type II (Au@TiO2 nanocomposites in which TiO2 was not pretreated with UV light) and TiO2 (P25). This shows that pretreatment of TiO2 provides type I a better catalytic activity.
Citation InformationMohammad Mansoob Khan and M. H. Cho. "Enhancement in the Photocatalytic Activity of Au@TiO2 Nanocomposites by Pretreatment of TiO2 with UV Light" Bulletin of Korean Chemical Society Vol. 33 Iss. 5 (2012)
Available at: http://works.bepress.com/mmansoob_khan/16/