Synthesis and characterization of TiO2/ZnO heterostructure for UV photocatalytic degrade DOM in landfill leachate

Abstract

TiO2/ZnO heterostructure photocatalysts were successfully fabricated via hydrothermal and solid-state reaction method. In TiO2/ZnO composite powder, TiO2 nanoparticles of anatase phase are well distributed on the surface and edge of ZnO with wurtzite phase structure, and closely combined to form heterostructure. The optical bandgap of TiO2/ZnO powder is less than that of pure ZnO or TiO2 powder. TiO2/ZnO composite powders show higher degradation efficiency for methylene blue and dissolved organic matter. The degradation rate of TiO2/ZnO powder for fulvic acid-like substances in landfill leachate is 2.99 times that of pure ZnO powder and 1.30 times that of pure TiO2 powder. The degradation of fulvic acid-like substances by photocatalyst causes the decrease of some high molecular weight and benzene ring structure substances in leachate. The effective separation of electron and hole by the heterostructure in TiO2/ZnO powder is the main reason for its high photocatalytic degradation efficiency of DOM in landfill leachate.