Reduced-graphene-oxide-wrapped BiOI-AgI heterostructured nanocomposite as a high-performance photocatalyst for dye degradation under solar light irradiation

Solar photocatalytic water treatment has emerged as a promising way to provide clean water. However, most traditional photocatalysts (TiO₂, ZnO, etc.) are active only under ultraviolet light and have high recombination rates of photoinduced electron-hole pairs; therefore, they are not sufficient to fulfill all of the demands of practical applications. This problem could be overcome by developing highly solar-light-active and durable heterostructured photocatalysts. In this study, a new solar-light-active heterostructured reduced graphene oxide (RGO)/BiOI/AgI photocatalyst was successfully fabricated through a simple precipitation method. The resultant heterostructured RGO/BiOI/AgI nanocomposite exhibited extraordinary photocatalytic performance in the degradation of rhodamine B (RhB) under simulated sunlight irradiation. The measured rate constant of the RGO/BiOI/AgI nanocomposite was six times higher than that of bare BiOI nanostructures. Its extraordinary capacity for harvesting full-spectrum light and long-term stability makes the RGO/BiOI/AgI nanocomposite a potential photocatalyst for environmental remediation.