▎ 摘　　要

In this paper, graphene-cuprous oxide (G-Cu2O) composites were synthesized at room temperature using graphene oxide (GO) as two-dimensional support. From Zeta potential analysis, the surface charge of G-Cu2O composites altered from positive to negative, which favors the adsorption and photodegradation of positively charged dyes. Compared with Cu2O under similar synthesis condition, the G-Cu2O composites demonstrated improved photodegradation activity for methylene blue (MB) dye under visible light. Controlled experiments indicated that the G-Cu2O composite synthesized with 80 mg GO in the reaction system possessed more negative Zeta potential, highest specific surface area and thus presented the highest photocatalytic activity. Electrons mechanism for the improved photocatalytic performance of G-Cu2O composite was proposed in the degradation of MB. (C) 2011 Elsevier Masson SAS. All rights reserved.