Exploring Ligand-Controlled C2 Product Selectivity in Carbon Dioxide Reduction with Copper Metal-Organic Framework Nanosheets

The suitable choice of an electrocatalyst is crucial in controllingthe selectivity of electrocatalytic CO2 reduction products. Herein, we have explored the effect of different ligand environments in 2D metal-organic frameworks (MOFs), viz., copper naphthalenedicarboxylate (Cu-UNDC) and copper benzenedicarboxylate (Cu-UBDC). The change ofligand modulates the structure of the MOFs as well as the electronic environment around the copper center. The variation in the electronic structure and the coordination environment of the active Cu center changes the selectivity toward C-2 products. In the electrocatalytic process, Cu-UNDC produced 24.3% Faradaic efficiency (FE) for the C-2 products-far better than that of Cu-UBDC (13.2%). In contrast to electrocatalytic CO2RR, in the presenceof light, Cu-UBDC (26.2%) achieved a better FE for the C-2 products than Cu-UNDC (21.8%).

Automated summary

The appropriate choice of an electrocatalyst is crucial for controlling the selectivity of electrocatalytic CO2 reduction products. This study explores the effect of different ligand environments on 2D metal-organic frameworks (MOFs), namely copper naphthalenedicarboxylate (Cu-UNDC) and copper benzenedicarboxylate (Cu-UBDC). The change in ligand modulates the structure of the MOFs as well as the electronic environment around the copper center, resulting in altered selectivity towards C-2 products. Cu-UNDC exhibits a significantly higher Faradaic efficiency (FE) of 24.3% for C-2 products in the electrocatalytic process compared to Cu-UBDC (13.2%). However, under light irradiation, Cu-UBDC achieves a higher FE of 26.2% for C-2 products compared to Cu-UNDC (21.8%) in contrast to electrocatalytic CO2 reduction.