This study explores various approaches to enhancing the activity and selectivity of gas-phase photocatalytic CO 2 reduction under humid conditions by implementing and optimizing bimetallic M–Cu systems (M = Pt, Pd, Au, Ag) supported on titanium dioxide (TiO 2 ). By tuning the total metal content, the molar ratio between M and Cu, the deposition method, and the nature of the TiO 2 support, it is possible to create a synergy between copper and the secondary metal, each contributing its own advantages while minimizing drawbacks. This strategy also improves the stability of the systems by increasing their resistance to Cu oxidation. These results offer a promising pathway for the development of efficient photocatalysts for solar-driven gas-phase CO 2 conversion into chemical fuels.
Marchal et al. (2025) studied this question.