Atomically precise metal nanocluster sandwich heterojunction for robust and efficient photocatalytic CO2 reduction to methanol

Abstract

Developing heterogeneous nanocatalysts with a well-defined structure and excellent reactivity and stability is vital for understanding catalytic mechanisms and practical industrial applications. Herein, we reported the construction of an atomically precise metal nanocluster sandwich heterojunction (MIL-125-NH₂-Au₂₅(L-Cys)₁₈/g-C₃N₄, M-A/C for short). Compared with the binary counterparts, the M-A/C efficiently and selectively photocatalyzed CO₂ reduction to methanol under visible light irradiation with remarkably enhanced activity and stability due to the protective shell. Moreover, the ternary M-A/C heterojunction not only broadened the light absorption region and strengthened CO₂ adsorption but also expanded the interfacial charge transfer channel, benefiting photocatalytic performance. Additionally, the integration of precise structure and in situ spectrometry unveiled the evolution from CO₂ to CH₃OH. This work opens a promising avenue for designing a highly efficient and robust atomically precise metal cluster-based heterojunction catalyst.