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

Abstract K-doped ZnO/La 2 O 3 composite photocatalyst was synthesized via facile sol–gel route using glucose as a complexing agent. The concentrations of K and La 2 O 3 were varied, it was found that the formation of ZnO/La 2 O 3 composite mainly lay in the promotional effect of potassium and 10 mol% content of K-doping was optimum to obtain ZnO/La 2 O 3 composite. The results showed that, in contrast to pure ZnO and undoped ZnO/La 2 O 3 , K-doping greatly changed the microstructure, morphology, optical property and photocatalytic performance of ZnO/La 2 O 3 composite. The photocatalytic activity of K-doped ZnO/La 2 O 3 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 La 2 O 3 .