Chinese Journal of Catalysis ›› 2023, Vol. 50: 361-371.DOI: 10.1016/S1872-2067(23)64448-1

• Articles • Previous Articles     Next Articles

Infiltration of C-ring into crystalline carbon nitride S-scheme homojunction for photocatalytic hydrogen evolution

Zhihan Yua,b, Chen Guana,b, Xiaoyang Yuea,b, Quanjun Xianga,b,*()   

  1. aState Key Laboratory of Electronic Thin Film and Integrated Devices, School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, China
    bYangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou 313001, Zhejiang, China
  • Received:2023-03-31 Accepted:2023-04-30 Online:2023-07-18 Published:2023-07-25
  • Contact: *E-mail: (Q. Xiang).
  • Supported by:
    National Natural Science Foundation of China(22272019);Sichuan Science and Technology Program(2022ZYD0039);Sichuan Science and Technology Program(2022JDRC0096);Sichuan Science and Technology Program(2022NSFSC1213);Sichuan Science and Technology Program(2022NSFSC0870);Sichuan Science and Technology Program(2023NSFSC1069);Open Foundation of State Key Laboratory of Electronic Thin Films and Integrated Devices(KFJJ202105)


Enhancing the carrier separation in graphitized carbon nitride (g-C3N4) is advantageous for improving its photocatalytic activity. Herein, we propose a feasible method for preparing CN-C by thermal polymerization to gradually infiltrate carbon rings (C-rings) into the surface of crystalline carbon nitride (CN), enabling photogenerated electrons to be transferred rapidly between the CN inner layers and the CN/C outer layer. Successful penetration and distribution of carbon rings into carbon nitride were confirmed by secondary ion mass spectroscopy using ratio analysis of C and N elements at various depths of the prepared photocatalyst. Theoretical calculations indicated that CN and CN/C in the molecule generated different Fermi levels to form an S-scheme homojunction, establishing appropriate built-in electric fields and thus enabling interlayer charge migration. Moreover, the overlap of the conjugate plane of C-rings with carbon nitride led to the formation of photogenerated in-plane charge transfer tunnels. The two-electron transfer tunnels greatly improved the dissociation efficiency of photogenerated electrons. The prepared sample loaded with 3 wt% Pt as a co-catalyst for hydrogen production under visible light irradiation, and the prepared optimal sample CN-C showed a maximum quantum efficiency of 15.56% for photocatalytic H2 evolution at 385 nm. This research introduces a new idea for constructing a directional transfer path for charge carriers in-plane and intralayer.

Key words: Carbon ring, S-scheme, Interlayer charge transfer, Homojunction, Photocatalytic hydrogen evolution reaction