Preparation and characterization of SnO2/ZnO/TiO2 composite semiconductor with enhanced photocatalytic activity

► Synthesis of SnO2/ZnO/TiO2 composite photocatalyst using sol-gel and solid-state methods. ► The structure of composites is investigated by XRD, Raman, XPS and SEM. ► Composite semiconductors show the enhanced catalytic activity under UV and visible light. ► High activity is attributed to the increased separation of the charge carriers.