Integrating S-scheme photocatalysis with tandem carbonylation: A green and scalable strategy for CO2 valorization

The rapid increase in atmospheric CO₂ levels due to industrialization underscores the urgent need for innovative carbon valorization strategies. Photocatalytic CO₂ reduction presents a sustainable solution; however, conventional systems suffer from inefficient charge separation and limited product applicability. Herein, a green and scalable tandem strategy is developed by integrating S-scheme photocatalysis with palladium-catalyzed carbonylation. A rationally designed CeO₂/Bi₂S₃ heterojunction leverages its hierarchical structure, broad visible-light absorption, oxygen-vacancy-mediated charge dynamics, and the S-scheme charge transfer mechanism to achieve highly efficient photocatalytic CO₂-to-CO conversion (14.05 mmol g⁻¹, 98% selectivity). The generated CO is directly utilized in a subsequent carbonylation reaction under mild conditions, yielding high-value amides with near-quantitative CO utilization. This integrated approach eliminates the risks of CO handling and enhances economic viability, providing a direct and effective route for converting CO₂ into fine chemicals. By bridging photocatalysis with industrial catalysis, this work advances sustainable carbon recycling technologies and opens avenues for the development of efficient CO₂ conversion systems.