A peculiar mechanism for the photocatalytic reduction of decabromodiphenyl ether over reduced graphene oxide-TiO2 photocatalyst

摘要: Abstract There remains a significant need for new approaches to photocatalytically destroy refractory halogenated pollutants. Here, efficient photocatalysts (RGO/TiO2) were prepared by UV treatment of graphene oxide (GO) mixed with Degussa P25 TiO2, and used reduce decabromodiphenyl ether (BDE209). The optimized composite yielded BDE209 degradation 72.0% debromination 59.4% in anoxic water methanol as electron donors after 12 h irradiation, being 2 4 times that over naked respectively. reduction generated 3Br–9Br PBDEs congeners, which further debrominated. This led 90% at 24 h reaction. Unlike the stepwise manner commonly observed UV–TiO2, generation, accumulation distribution intermediates time course implied skipped some steps. A novel mechanism multi-electron induced pathway was proposed. originated from abilities reduced GO storing transporting electrons. RGO not only trapped electrons improve charge separation on but also shuttled accumulated initiate transfer BDE209. markedly enhanced demonstrates RGO/TiO2 provide green method remove