Facile One-Step Sonochemical Synthesis and Photocatalytic Properties of Graphene/AgPO Quantum Dots Composites.

In this study, a novel graphene/AgPO quantum dot (rGO/AgPO QD) composite was successfully synthesized via a facile one-step photo-ultrasonic-assisted reduction method for the first time. The composites were analyzed by various techniques. According to the obtained results, AgPO QDs with a size of 1-4 nm were uniformly dispersed on rGO nanosheets to form rGO/AgPO QD composites. The photocatalytic activity of rGO/AgPO QD composites was evaluated by the decomposition of methylene blue (MB). Meanwhile, effects of the surfactant dosage and the amount of rGO on the photocatalytic activity were also investigated. It was found that rGO/AgPO QDs (W:W = 2.3%) composite exhibited better photocatalytic activity and stability with degrading 97.5% of MB within 5 min. The improved photocatalytic activities and stabilities were majorly related to the synergistic effect between AgPO QDs and rGO with high specific surface area, which gave rise to efficient interfacial transfer of photogenerated electrons and holes on both materials. Moreover, possible formation and photocatalytic mechanisms of rGO/AgPO QDs were proposed. The obtained rGO/AgPO QDs photocatalysts would have great potentials in sewage treatment and water splitting.