Preparation and study of Z-type heterojunction composite photocatalytic material with Ag2MoO4 modified rosette-like Bi2WO6 with Ag-SPR promoting effect

Abstract

Here, the novel Ag 2 MoO 4 /Bi 2 WO 6 ( AMO/BWO ) heterojunction composite photocatalysts were synthesized by a two-step method (co-precipitation method + hydrothermal method) and characterized by a variety of characterization techniques including XRD, XPS, SEM, TEM, UV-vis DR spectroscopy, PL spectroscopy and FTIR spectroscopy, as well as EIS analyses, and photocurrent response for confirming the formation of Z-type heterojunctions. The generation and transfer of electron/holes in the AMO/BWO heterojunctions excited by simulated sunlight were analyzed. Under simulated sunlight, the photocatalytic performance of AMO/BWO composites were studied by degradation of organic pollutants. The experimental results show that the 30wt%AMO@BWO is the best photocatalytic composite material among all samples. Due to the prolonging of lifetime of the photoexcited electrons in the CB of AMO and holes in the VB of BWO, these carriers are more effective to participate in photodegradation reactions. An electron/hole transfer mechanism of the Z-scheme heterojunctions is proposed to illustrate the enhanced photodegradation performance of the AMO/BWO composite samples.