▎ 摘　　要

Effective separation of charge and high cycle stability are key factors for photocatalyst application. In this paper, the spatially separated Pt/CdS/N-ZnO/CoOx graphene microtubule (PCNZCo-GM) is prepared by a capillary action assisted hydrothermal method for enhancing charge separation efficiency and photocatalytic oxidation ability. In the spatially separated composite, Pt as an electron collector and CoOx as a hole collector were selectively decorated on the inner and outer surfaces of the CdS/N-ZnO graphene microtubule, which prompts photogenerated electrons and holes near the surface to move in the opposite direction. N-ZnO possesses a wider light absorption range, and the construction of a Z-scheme heterojunction between CdS and N-ZnO can effectively promote the charge separation. The graphene microtubule structure with an oxidation-reduction cocatalyst supported on its inner and outer surfaces is conducive to charge separation, reusability and mass transfer in photocatalytic processes. The PCNZCo-GM composite photocatalyst displays a remarkable photocatalytic oxidation efficiency for methyl orange (MO, 93% removal efficiency in 60 min) and an excellent bacterial inactivation rate of almost 100% under 60 min of illumination. Based on the macroscopic appearance and preferable mechanical strength of the 3D graphene microtubule, the PCNZCo-GM composite possesses high cycle stability in photocatalytic processes and its excellent photocatalytic performance was well maintained after five applications.