▎ 摘　　要

Zero bandgap and water soluble sulfonated graphene (SGE) has been introduced into an n-type semiconductor photocatalytic system to fabricate a Ag@AgBr/SGE composite photocatalyst. Due to its unique conduction and valence band dispersion and low Fermi level, SGE serves as an electron reservoir within the photocatalyst which enhances the charge carrier transfer and separation significantly. Furthermore, the stability and adsorptivity of Ag@AgBr/SGE are also improved owing to the sulfonic acid groups and conjugated sp(2) carbon network of SGE. The photocatalytic activity was found to be 11-fold higher than SGE-free Ag@AgBr upon the photodegradation of MO under visible light irradiation. This work provides a novel and in-depth perspective for understanding the graphene-involved photocatalytic mechanism and would stimulate the development of graphene-involved photocatalysts for the exploitation and utilization of solar energy.