J. Mater. Sci. Technol. ›› 2023, Vol. 168: 35-49.DOI: 10.1016/j.jmst.2023.05.033

• Research Article • Previous Articles     Next Articles

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

Zhiyang Lia,b, Yaogang Chenc, Yinghe Zhangd,*, Wei Aib, Qian Leib, Tingjun Yaob, Dan Zhonga, Wenjie Liua, Wenbiao Jina, Lei Yanga,*   

  1. aState Key Laboratory of Urban Water Resource and Environment, Shenzhen Key Laboratory of Organic Pollution Prevention and Control, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China;
    bKey Laboratory of Northwest Water Resources, Environment and Ecology, Ministry of Education, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China;
    cCNAS Accredited Test Center, Guangdong Engineering Technology Research Center of Air Purification, Healthlead Co., Ltd., Shenzhen 518055, China;
    dSchool of Science, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
  • Received:2023-03-31 Revised:2023-05-08 Accepted:2023-05-15 Published:2024-01-01 Online:2023-12-25
  • Contact: *E-mail addresses: carolinew2006@163.com (Y. Zhang), yanglei2020@hit.edu.cn (L. Yang)

Abstract: 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 refractory micropollutant removal and simultaneous hydrogen (H2) evolution respectively compared to conventional ZnO/g-C3N4 Step-scheme heterojunction. The apparent quantum efficiency of the ZCN0.4 heterojunction reaches 0.92% (λ = 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 spectrum, meanwhile, the built-in electric field generated during Fermi level alignment accompanying favorable 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 H2 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. Considering the outstanding performance in photocatalysis, the ZCN system exhibits broad potential for practical applications in water pollution control and green energy production.

Key words: ZnO, C3N4-Cg, Heterojunction, Photodegradation, Hydrogen evolution