Synthesis and photocatalytic performance of BiOCl/graphene composite with tight interfacial contact and highly exposed (001) facets

The BiOCl/graphene composite was synthesized by vapor-thermal method. The morphologies, structures, chemical states, and optical properties of the samples were systematically characterized. The visible light catalytic activity of the composite was studied by degrading methylene blue (MB). The results show that the sample obtained with 300-mg BiCl3 and 1-mg graphene (named Bi(300)GP(1)) forms Bi-C bond, has highly exposed (001) facets, forms a tight contact between BiOCl and graphene, and has more electron transfer channels, which effectively promoted the separation and migration of photoexcited carriers. In addition, the introduction of electronic states near the top of the valence band improved the visible light absorption of the sample, and the degradation rate of MB was the highest, which was increased from 76.64% to 98.12%. Meanwhile, it was confirmed by the ESR test that center dot O-2(-) played a major role in the photocatalytic degradation process.