Template-free synthesis of hollow TiO2 nanospheres supported Pt for selective photocatalytic oxidation of benzyl alcohol to benzaldehyde

Heterogeneous photocatalytic system are widely applied to degrade organic pollutants or converse into high value-added chemicals. Both environmental and energy aspects should be considered to improve these chemical processes, favoring reaction conditions that involve room temperature and ambient O2 pressure. In the present work, hollow titanium dioxide nanospheres were fabricated via template-free method. The prepared samples were characterized by X-ray diffraction, N2 adsorption–desorption isotherms, transmission electron microscopy, and X-ray photoelectron spectroscopy. The photocatalytic activity was evaluated by photocatalytic oxidation of benzyl alcohol to benzaldehyde with visible light under atmospheric pressure at room temperature. The designed hollow structure (2%Pt–TiO2–5) not only exhibited a very high surface area, but also promoted photonic behavior and multiple light scattering, which as an efficient photocatalyst performed moderate conversion (about 20%) and high selectivity (> 99%) for oxidation of benzyl alcohol to benzaldehyde at room temperature with visible light in solvent of toluene. This work suggests that both hollow structure and Pt nanoparticles have great potential for execution of oxidative transformations under visible light. Keywords: Titanium dioxide, Hollow nanospheres, Photocatalytic oxidation, Benzyl alcohol, Visible light