Investigating the Heteronjunction between ZnO/Fe2O3 and g-C3N4 for an Enhanced Photocatalytic H2 production under visible-light irradiation

Abstract

A series of ZnO/Fe2O3/g-C3N4 photocatalysts were synthetized by impregnation of g-C3N4 with Zn(NO3)2·6H2O, and Fe(NO3)2·9H2O followed by calcination. The morphology, chemical composition, and structure of the resulted materials were carefully analyzed by various characterization techniques. The photocatalytic performance of ZnO/Fe2O3/g-C3N4 composites was evaluated based on the H2 evolution from water splitting reaction. The results showed that the ZnO/Fe2O3/g-C3N4 composite can effectively produce more H2 than pure g-C3N4 when irradiated under visible-light. H2 production rate over 3-ZnO/Fe2O3/g-C3N4 composite was of 25 μmol·h−1, which is 4 times higher than that obtained in the presence of pure g-C3N4, clearly showing a significant improvement of the photocatalytic activity of the prepared nanocomposite. This result was attributed to the formation of a heterojunction between g-C3N4 and ZnO/Fe2O3, which delayed the recombination of holes-electrons pairs and resulted in a remarkable increase in photocatalytic performance.