▎ 摘　　要

A series of graphene oxide (GO)/Ag3PO4 composites were synthesized using ion exchange-chemical precipitation method with different GO content, and the photocatalytic reduction degradation effect on decabromodiphenyl ether (BDE-209) over GO/Ag3PO4 was also studied. The optimized composite exhibited superior photocatalytic activity. When the content of GO was 7%, the degradation efficiency of BDE-209 could reach 97.33% in anoxic water with methanol as electron donors after 8 h of visible light irradiation, being 3 times that over pure Ag3PO4 and the BDE-209 reduction generated 3Br-8Br PBDEs congeners. The photocatalytic degradation of BDE-209 has been further investigated under different reaction conditions, such as photocatalyst dosage and pH of reaction system. According to analysis of the intermediates's generation, accumulation and distribution, we proposed that the BDE-209 reduction mechanism was the multi-electron reduction process. GO not only trapped electrons to improve the charge separation on Ag3PO4, but also fleetingly transferred the accumulated electrons to BDE-209. This study indicates that GO/Ag3PO4 could be a promising material for environmental treatment of persistent pollutants. (C) 2017 Elsevier B.V. All rights reserved.