CO2 reduction to formate on an affordable bismuth metal-organic framework based catalyst

Abstract

Electrochemical reduction of carbon dioxide (CO2) into green fuels and valuable chemicals is an up-and-coming method of CO2 valorization. Formate/formic acid is one the most desirable product among the many other possible chemicals that can be generated from CO2. Herein, we report on a simple and tunable method to prepare Bi-based electrocatalyst. An affordable metal-organic framework (MOF) precursor TAL-33 has been utilized upon carbonization. This MOF was fabricated from a novel modular carbon-rich ligand 1H-benzo[d]imidazole-5,6-diol and bismuth chloride. Cyclic voltammetry and chronoamperometric measurements were performed to investigate the electrocatalytic activity and selectivity towards the formate. The most promising samples have shown high Faradaic efficiency and stability. The in-depth physical characterization of catalyst structure (XPS, XRD, SEM, and TEM) was performed to investigate the structure-activity relationships. Theoretical studies have been performed to confirm that the enhanced CO2 electroreduction to formate is linked to the presence of metallic bismuth sites.