Efficient CO2 Reduction to HCOOH with High Selectivity and Energy Efficiency over Bi/rGO Catalyst

Abstract The electroreduction of carbon dioxide (CO 2 ) to value‐added fuels is of great significance to meet the ever‐increasing energy and environmental challenges. So far, desirable selectivity and Faradaic efficiency for CO 2 reduction can be obtained over most electrocatalysts. However, improving cathodic energy efficiency is still neglected in research. Herein, a facile reduction method is first presented to synthesize the ultrafine non‐noble bismuth (Bi) nanoparticles anchored on rGO (Bi/rGO). As expected, the Bi/rGO catalyst exhibits excellent electrochemical performance on CO 2 reduction to form formic acid (HCOOH), with very high Faradaic efficiency (up to 98%), favorable stability (over 12 h), and especially outstanding cathodic energy efficiency (up to 71%). Further, density functional theory (DFT) calculations are performed to investigate the possible reaction mechanism for reduction of CO 2 to HCOOH.