MOFs-based single/dual-atom catalysts: atomically active sites engineering for efficient CO₂ reduction

The excessive emission of CO₂ has seriously threatened the global climate environment and human health, the efficient CO₂ reduction reaction (CO₂RR) as an effective method to reduce CO₂ emissions has become a hot spot in the current catalyst field. Metal-organic frameworks (MOFs) serve as ideal substrates for the preparation of single-atom catalysts (SACs) and dual-atom catalysts (DACs), attributed to their distinctive structure and superior pore characteristics. These catalysts address the issues of inadequate selectivity and activity in CO₂RR by facilitating efficient electron transfer at the atomic level. This review provides an overview of the design strategies for active sites in MOFs-based SACs and DACs, focusing on the synergy between single-atom and multi-atom configurations. It comprehensively summarizes the mechanisms of both photocatalytic and electrocatalytic CO₂RR and the relationship between active sites and catalytic efficiency. Additionally, the review provides an in-depth discussion of their applications in electrocatalysis and photocatalysis of CO₂RR, highlighting specific examples and advancements in these fields. Finally, the challenges of the future directions for active sites design and the development of improving catalytic activity in CO₂RR at industrial current density of MOFs-based SACs/DACs were looked forward.