Enhanced degradation performance of organic dyes removal by semiconductor/MOF/graphene oxide composites under visible light irradiation

A novel BiVO4/MOF/GO ternary photocatalyst was prepared by hydrothermal method, and was characterized by XRD, SEM, EDS, TEM, FT-IR, XPS, BET, UV-Vis DRS and PL. The as-prepared BiVO4/MOF/GO composites displayed the standout photocatalytic activity towards the degradation of Rhodamine B (RhB) under visible light irradiation, which caused by MOF, BiVO4 and grapheme oxide have combined to produce the synergistic effect. And the topgallant composite referred to BFG-2 that showed the highest photocatalytic activity. In the light of the active species trapping experiments, the center dot OH and center dot O-2(-) radicals were the two main active radicals in the photocatalytic tests. The enhanced photocatalytic performance is chiefly ascribed to the formation of the tight joint interface in BiVO4/MOF/GO composites, in which GO has the excellent conductivity and adsorption effect during the photodegradation process, and this hybrid structure is beneficial to increase the surface active site of the catalyst compared the pure one. Moreover, this synergistic effect is propitious to the transfer and separation of photo-generated carriers. At the same time, the BiVO4/MOF/GO composite photocatalyst can maintain a stable photocatalytic activity and structure after four cycles. Finally, the possible mechanism of photocatalytic degradation of RhB was put forward.