Enhanced optical, visible light catalytic and electrochemical properties of Au@TiO2 nanocomposites

Au@TiO2 nanocomposites and pure TiO2 were successfully used to know the effect of Au on TiO2 and their comparative optical, visible light catalytic and electrochemical activities were investigated. Optical parameters such as band gap energy (Eg = 2.4 eV), absorption coefficient (α), refractive index (n) and dielectric constants (σ) have been determined using different methods. Visible light (λ = ∼590 nm) catalytic activity of Au@TiO2 nanocomposites was performed for reducing methyl orange (MO) under visible light irradiation. CV, EIS and DPV studies demonstrate that Au@TiO2 nanocomposites exhibit redox behavior, charged its surface by accumulating electrons, store and release the electrons.