Tuning interfacial charge transfer for efficient visible-light-driven photodegradation and simultaneous H2 evolution

The edge-graphitized carbon nitride (C3N4-Cg) was prepared by secondary pyrolysis to construct ZnO/C3N4-Cg (ZCN) type -II heterojunction photocatalyst via a facile sonication dispersion method, which achieved-7.04-fold and-18.3-fold enhanced visible-light-driven photocatalytic performance for refrac-tory micropollutant removal and simultaneous hydrogen (H 2 ) evolution respectively compared to con-ventional ZnO/g-C3N4 Step-scheme heterojunction. The apparent quantum efficiency of the ZCN0.4 het-erojunction reaches 0.92% (& lambda; = 420 nm). Such excellent performance stems from that the edge-graphene moieties stitched onto the interface of heterojunction extend light absorption to the full visible spec-trum, meanwhile, the built-in electric field generated during Fermi level alignment accompanying fa-vorable band-bending structure provides an effective pathway for the rapid migration of photoinduced electrons via the edge graphene channel to improve interfacial charge separation efficiency. Interestingly, the midgap states introduced in ZCN heterojunction could temporarily retain photoexcited electrons to effectively inhibit the in situ carrier recombination for improved photocatalytic H 2 evolution. Moreover, ZCN/peroxymonosulfate system exhibited excellent anti-interference performance against complex water bodies under visible illumination due to the synergistic effect between the co-existing anions and organic matter. Meanwhile, the eco-friendly nature of the ZCN/peroxymonosulfate system showed no biotoxicity of reaction filtrate on cell proliferation after treatment, which avoided secondary contamination. Consid-ering the outstanding performance in photocatalysis, the ZCN system exhibits broad potential for practical applications in water pollution control and green energy production.& COPY; 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.