Efficient selectivity of dual-metal intermediate structure in metal-organic frameworks-based photocatalyst for customized the pathway of CO2 reduction to CO.

The capture and utilization of CO2 are critical for protecting the environment and ensuring the sustainable development of society. Given the challenges in separating multiple C1 products (CO, CH4, etc.) with similar reduction potentials, achieving high selectivity for a single reduction product while maintaining high conversion efficiency is essential. In this study, a photocatalyst with NH2-MIL-125-Ti/Cu dual-metal active sites was developed by introducing Cu2+ in situ. The synergistic interaction between oxygen vacancies that capture CO2 and the Cu-Ti dual active sites formed by CuCOTi intermediates preferentially facilitated the generation of CO. As a result, high CO selectivity was achieved during the CO2 photoreduction process. The experimental results indicate that NH2-MIL-125-Ti/Cu5 achieves nearly 100 % selectivity for CO under visible-light irradiation, with a CO2-to-CO conversion rate of 598.2 μmol g-1 h-1, representing a 108.28 % improvement compared to NM. This study provides a novel strategy for designing and synthesizing more efficient and selective photocatalysts.