Ultraviolet photocatalytic degradation of methyl orange by nanostructured TiO2/ZnO heterojunctions

Abstract

Nanostructured TiO₂/ZnO heterojunctions with the morphologies of hedgehogs and fan blades were synthesized by a solvothermal method and characterized by means of XRD, SEM, TEM, BET, FT-IR, Raman, XPS, UV-vis and PL diffuse reflection spectroscopy. The photocatalytic activities of both TiO₂/ZnO hedgehogs and fan blades for the degradation of methyl orange (MO) were explored under UV light; the hedgehogs exhibited the best photocatalytic activity (97% MO degradation within 30 min) owing to the hierarchical nanostructure with a large surface area. The degradation mechanism is discussed based on the band structure. Both heterojunctions are very promising for the degradation of MO from organic dyestuff in engineering practice.