Construction of Z-scheme Fe2O3@e-HNbWO6 composite and its enhanced photocatalytic activity

A direct Z-scheme Fe2O3@e-HNbWO6 heterojunction photocatalyst was assembled by the co-precipitation procedure under the moderate conditions. The structures, spectral response characteristics, morphology, and composites of the as-prepared samples were characterized. Furthermore, the photocatalytic experiment towards the degradation of Rhodamine B (RhB) solution under simulated sunlight irradiation was investigated. It was found that the Fe2O3@e-HNbWO6 composite exhibit excellent photocatalytic activity. In accordance with the active species trapping experiment, photocurrent responses, and electrochemical impedance spectroscopy analysis, the possible enhanced photocatalytic performance of the Fe2O3@e-HNbWO6 composite could be explained by a direct Z-scheme photocatalytic mechanism. This direct Z-scheme heterojunction can not only improve the separation efficiency of photogenerated carriers, but also increase the redox ability for excellent photocatalytic activities. The present study provides an effective approach to design and fabrication of niobium-based direct Z-scheme heterojunction for improve its photocatalytic performance.