Enhanced reactive oxygen species activation for building carbon quantum dots modified Bi5O7I nanorod composites and optimized visible-light-response photocatalytic performance.

Novel Carbon quantum dots modified Bi5O7I (CQDs/Bi5O7I) nanorod composites were prepared via an ionic liquid 1-ethyl-3-methylimidazolium iodide ([Emim]I) assisted solvothermal method for the first time. Series of characterization methods were used to explore the structural composition, morphology and optical properties of as-prepared CQDs/Bi5O7I photocatalysts. Compared with pure Bi5O7I nanorod, CQDs/Bi5O7I composites exhibited the increased the specific surface area and visible light capture capability so as to expose more active sites and make full use of sunlight. Meanwhile, the tight contact between CQDs and Bi5O7I was beneficial for the rapid separation and migration of photogenerated electron-hole pairs to further suppress the high recombination rate in the pure Bi5O7I nanorods. More generated superoxide radicals (O2-) was detected by electron spin resonance analysis. In addition, the possible mechanism for the enhanced photocatalytic performance of CQDs/Bi5O7I composites was put forward.