Synthesis of hollow shell TiO2 nanostructures enclosing Au nanoparticles and evaluation of their photoelectrocatalytic activity

Abstract

Titania hollow shell structures enclosing Au nanoparticles (NPs) Void@Au@TiO2 were synthesized and applied for photoelectrochemical and chemical catalysis. SiO2 nanospheres were first synthesized to be used as templates for the nanostructures. These SiO2 nanospheres were then functionalized with gold nanoparticles (Au NP) using a bifunctional linker APTES [(3-Aminopropyl)triethoxysilane]. A titania coating was carried out on these Au-decorated SiO2 spheres, followed by calcination to enhance the crystallinity of these SiO2@Au@TiO2 structures. Thereafter, the SiO2 template was etched out using NaOH leaving behind Au NPs encapsulated in TiO2 hollow shell nanospheres Void@Au@TiO2. These structures were characterized by using TEM, XRD, UV–Vis-DRS, Raman and FTIR spectroscopy. The catalytic activity was evaluated using the selective oxidation of 4-methoxy benzyl alcohol as a test reaction. Further the photo-electrocatalytic activity of these nanostructures was evaluated.