Boosting Electrochemical CO2 Reduction on Metal-Organic Frameworks via Ligand Doping

Abstract

Electrochemical CO₂ reduction relies on the availability of highly efficient and selective catalysts. Herein, we report a general strategy to boost the activity of metal-organic frameworks (MOFs) towards CO₂ reduction via ligand doping. A strong electron-donating molecule of 1,10-phenanthroline was doped into Zn-based MOFs of zeolitic imidazolate framework-8 (ZIF-8) as CO₂ reduction electrocatalyst. Experimental and theoretical evidences reveal that the electron-donating nature of phenanthroline enables a charge transfer, which induces adjacent active sites at the sp² C atoms in the imidazole ligand possessing more electrons, and facilitates the generation of *COOH, hence leading to improved activity and Faradaic efficiency towards CO production.

Keywords: CO2 electrochemical reduction; ZIF-8; charge transfer; ligand doping; metal-organic frameworks.