Investigation on a novel ZnO/TiO2–B photocatalyst with enhanced visible photocatalytic activity

• A new kind of visible light activated photocatalyst was prepared by combining ZnO with B-doped TiO2 via the sol–gel method.
• B dopants energy level narrowed the band gap.
• Combined ZnO suppressed the recombination of photogenerated carriers.

A new type of composite photocatalysts (ZnO/TiO2–B) with Zinc oxide nanoparticles dispersed on boron doped titanium dioxide was prepared via a sol–gel method. The as-prepared powders were characterized by HRTEM, XRD, XPS, UV–vis DRS, and PL techniques. The results reveal that B3+ ions are doped into the TiO2 lattice in interstitial mode, while ZnO nanoparticles are dispersed on the surface of TiO2. The absorption of photocatalysts was extended into visible light region and the photogenerated electrons and holes were separated efficiently. Hence, ZnO/TiO2–B composite photocatalyst exhibits much better photocatalytic activity than those of pure TiO2 and TiO2–B on photodegradation of 4-chlorophenol under visible light irradiation.