Acta Phys. -Chim. Sin. ›› 2025, Vol. 41 ›› Issue (6): 100067.doi: 10.1016/j.actphy.2025.100067

Special Issue: S-scheme heterojunction in photocatalysis

• ARTICLE • Previous Articles     Next Articles

Designing thermodynamically stable noble metal single-atom photocatalysts for highly efficient non-oxidative conversion of ethanol into high-purity hydrogen and value-added acetaldehyde

Yuchen Zhou1,2, Huanmin Liu1, Hongxing Li2,*(), Xinyu Song1, Yonghua Tang2, Peng Zhou1,*()   

  1. 1 Eco-environment and Resource Efficiency Research Laboratory, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, Guangdong Province, China
    2 School of Physics and Optoelectronics, Xiangtan University, Xiangtan 411105, Hunan Province, China
  • Received:2025-01-18 Revised:2025-02-16 Accepted:2025-02-17 Published:2025-04-19
  • Contact: Email: pengzhou1209@pku.edu.cn (Peng Zhou)hongxinglee@xtu.edu.cn (Hongxing Li)
  • Supported by:
    The project was supported by the start-up support from Peking University Shenzhen Graduate School and the National Natural Science Foundation Excellent Young Scientist Project, PKUSZ, China. The authors would like to thank the calculation support from Shuguang Supercomputer Center

Abstract:

The intrinsic surface atomic configuration of photocatalyst without unstable or difficult-to-generate atomic vacancies often limits the formation of effective interaction between metal single atom (MSA) cocatalyst and photocatalyst, thus inhibiting the stability and performance improvement of single-atom photocatalysts. In this study, we present a convenient and cost-effective photochemical oxygen reduction reaction (ORR) mechanism to prepare thermodynamically stable noble metal single-atom cocatalysts on TiO2 photocatalyst under mild condition (only consuming water and oxygen at 101325 Pa and 25 ℃). The first-principles simulation firstly theoretically reveals that the intrinsic surface configuration of TiO2 can only produce unstable Pt―O2 structure. However, ORR occurring on TiO2 can not only provide one foreign oxygen to coordinate with Pt single atom (PtSA), but also induce one surface lattice oxygen to move toward PtSA, promoting the formation of one thermodynamically stable Pt―O4 species, demonstrated by the experimental synthesis of PtSA on TiO2 in oxygen atmosphere instead of inert atmosphere. The obtained stable PtSA-TiO2 photocatalysts exhibit a photocatalytic rate of 320.4 mmol·g−1·h−1 for the coproduction of high-purity hydrogen and value-added acetaldehyde with a selectivity of 99.65%, three-fold higher than the activity of Pt nanoparticles-loaded TiO2. This strategy is further extended to other noble metals, such as Rh and Pd.

Key words: Metal single atom, Surface reconstruction, Thermal stability, Photocatalysis, Hydrogen