Fabrication of direct Z-scheme Cu2O@V-CN (octa) heterojunction with exposed (1 1 1) lattice planes and nitrogen-rich vacancies for rapid sterilization

The Z-scheme heterojunction has demonstrated significant potential for promoting photogenerated carrier separation. However, the rational design of all-solid Z-scheme heterojunctions catalysts and the controversies about carrier transfer path of direct Z-scheme heterojunctions catalysts face various challenges. Herein, a novel heterojunction, Cu 2 O@V-CN (octa), was fabricated using V-CN (carbon nitride with nitrogen-rich vacancies) in-situ electrostatic self-wrapping Cu 2 O octahedra. Density functional theory (DFT) calculations revealed that the separation of carriers across the Cu 2 O@V-CN (octa) heterointerface was directly mapped to the Z-scheme mechanism compared to Cu 2 O/V-CN (sphere). This is because the Cu 2 O octahedra expose more highly active (1   1   1) lattice planes with more terminal Cu atoms and V-CN with abundant nitrogen vacancies to form delocalized electronic structures like electronic reservoirs. This facilitates the wrapping of Cu 2 O octahedra by V-CN and protects their stability via tighter interfacial contact, thus enhancing the tunneling of carriers for rapid photocatalytic sterilization. These findings provide novel approaches for designing high-efficiency Cu 2 O-based photocatalytic antifoulants for practical applications.