Synthesis, characterization, photocatalytic activity of selenium vacancy in BiSeX and BiSeX/GO (X = Cl、Br、I) photocatalysts

Abstract

BiSeX (X = Cl, Br, I) belongs to the V–VI–VII compounds, known for their high dielectric constants, ferroelectric properties, excellent photoconductivity, and well-suited valence bands. In this study, we successfully synthesized a series of BiSeX compounds through a simple hydrothermal method. We then combined varying amounts of graphene oxide (GO) with BiSeX in an autoclave, heating the mixture at 100 °C for 4 h to create the binary composite photocatalyst BiSeX/GO. The resulting products were extensively characterized using XRD, SEM-EDS, DR-UV, GC, BET, PL, UV–Vis-NIR, and HR-XPS techniques. To assess the photocatalytic efficiency of BiSeX and BiSeX/GO, these catalysts were tested for the degradation of the organic pollutant crystal violet (CV), yielding significant outcomes. BiSeCl/GO-25 wt% demonstrated exceptional effectiveness in degrading CV dyes, achieving a maximum reaction rate constant (k) of 0.0465 h⁻¹. Additionally, the photocatalytic conversion of carbon dioxide into chemical fuels offers a promising strategy to tackle escalating environmental issues and holds potential for renewable energy development. Our research revealed that selenium vacancies in BiSeX act as adsorption sites, significantly enhancing electron transfer at the interface, resulting in high activity and selectivity for the carbon dioxide reduction reaction.