Chinese Journal of Catalysis ›› 2026, Vol. 81: 227-245.DOI: 10.1016/S1872-2067(25)64866-2

• Article • Previous Articles     Next Articles

Rational construction of MXene-derived TiO2/CoNiO2 dual-site S-scheme heterojunction for boosting C-C coupling toward efficient photocatalytic CO2-to-C2H4 conversion

Yongsheng Hua, Shiji Dua,c, Jihui Langa,b, Huilian Liua,b, Xuefei Lia,b, Qi Zhanga,b, Ming Lua,c, Xin Lia,b,c(), Binrong Lid(), Maobin Weia,b(), Lili Yanga,b()   

  1. a Key Laboratory of Functional Materials Physics and Chemistry of Ministry of Education, Jilin Normal University, Changchun 130103, Jilin, China
    b National Demonstration Center for Experimental Physics Education, Jilin Normal University, Siping 136000, Jilin, China
    c The Joint Laboratory of MAX/MXene Materials, Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education, Jilin Normal University, Changchun 130103, Jilin, China
    d National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, Jiangsu, China
  • Received:2025-07-20 Accepted:2025-09-18 Online:2026-02-18 Published:2025-12-26
  • Contact: *E-mail: xlwl@jlnu.edu.cn (X. Li),libr@usts.edu.cn (B. Li),jlsdzccw@126.com (M. Wei),llyang1980@126.com (L. Yang).
  • Supported by:
    program for the National Natural Science Foundation of China(22378158);program for the National Natural Science Foundation of China(22306142);development of Science and Technology of Jilin province(YDZJ202301ZYTS246);development of Science and Technology of Jilin province(20230508040RC);development of Science and Technology of Jilin province(20240601047RC);Cultivation Programme for Young and Middle-aged Innovative Teams in Science and Technology of Jilin Province(20250601083RC);program for the Industrial Technology and Development of Jilin Province Development and Reform Commission(2023C44-4);program for the Science and Technology of Education Department of Jilin Province(JJKH20250941KJ);Jiangsu Provincial Natural Science Foundation(BK20230656)

Abstract:

The CO2 photoreduction reaction (CO2RR) into C2H4 represents a highly promising technology for converting greenhouse gases into value-added chemicals. However, this technology faces challenges such as a high energy barrier in the C-C coupling process and a slow electron supply efficiency. In this study, we constructed Ti3C2 MXene-derived TiO2/CoNiO2 S-scheme heterojunction (MTC-X) by a simple in-situ growth process. The Co-Ni dual-site provided the structural foundation for C-C coupling, effectively reducing the energy barrier of the *CO-*COH intermediate coupling step. Meanwhile, the S-scheme heterojunction ensured the rapid supply of electrons and protons during the CO2RR, thereby enabling the efficient conversion of CO2 to C2H4. Notably, the MTC-2 sample exhibited the C2H4 production rate of 25.2 μmol·g-1·h-1, which was 23 times higher than that of the pure CoNiO2. In summary, by combining in-situ X-ray photoelectron spectroscopy, in-situ Kelvin probe force microscopy, femtosecond transient absorption spectroscopy and difference charge density calculation, confirmed the formation of the TiO2/CoNiO2 S-scheme heterojunction. Further, by photoelectrochemical tests, in-situ Fourier transform infrared spectroscopy, Gibbs free-energy calculations, elucidated the mechanism by which the Co-Ni dual-site structure and S-scheme heterojunction synergistically enhance the C-C coupling kinetic process. This provides new experimental reference and theoretical basis for the selective conversion of CO2 to C2H4.

Key words: CO2 photoreduction, CoNiO2, Ti3C2 MXene, S-scheme heterojunction