Enhanced photocatalytic activity of ZnO/La2O3 composite modified by potassium for phenol degradation

K-doped ZnO/La2O3 composite photocatalyst was synthesized via facile sol-gel route using glucose as a complexing agent. The concentrations of K and La2O3 were varied, it was found that the formation of ZnO/La2O3 composite mainly lay in the promotional effect of potassium and 10 mol% content of K-doping was optimum to obtain ZnO/La2O3 composite. The results showed that, in contrast to pure ZnO and undoped ZnO/La2O3, K-doping greatly changed the microstructure, morphology, optical property and photocatalytic performance of ZnO/La2O3 composite. The photocatalytic activity of K-doped ZnO/La2O3 composite yielded 98.5% degradation of phenol solution after 2.5 h visible light irradiation, which was explained by the synergetic effect generated by the introduction of both K and La2O3. (C) 2013 Elsevier B.V. All rights reserved.