LAUSR

Abstract In this work, a novel multiple-phase heterostructure of reduced graphene oxide/copper oxide/cuprous oxide (rGO/CuO/Cu2O) was proposed, where hierarchical ball-like CuO/Cu2O was grown on rGO in situ by a facile one-pot hydrothermal method. The obtained rGO/CuO/Cu2O heterojunction displayed superior photocatalytic activity with a 99.8% degradation rate for tetracycline (TC) under visible light. Moreover, the stability of the resultant rGO/CuO/Cu2O catalyst was significantly enhanced, where it maintained degradation rate above 90.7% even after 10 consecutive runs. The improved photocatalytic performance and durability of the rGO/CuO/Cu2O heterojunction could be attributed to the interface synergistic effect among CuO, Cu2O and the planner structure of rGO sheets which developed unprecedented polycrystalline structure. Also, rGO not only regarded as an acceptor and transporter of the photogenerated electrons, but also act as photosensitizer to increase the photon capture ability and protector to enhances photocatalytic stability. This work shows a new scheme system of rGO/CuO/Cu2O heterostructure and a more efficient Cu-based semiconductor photocatalyst toward water purification.