Development of a Fuel Cell for Simultaneous Power Generation and CO2 Reduction Using a Palladium Electrocatalyst

Mitigating global climate change requires advanced carbon capture, utilization, and storage technologies that can efficiently convert captured CO2 into valuable chemical products and fuels. This study aimed to enhance the efficiency of electrochemical CO2 reduction in a H2–CO2 fuel cell by exploiting the H+-involved chemical equilibrium of CO2 reduction reactions. Because Pd electrocatalysts reportedly interact favorably with H+, a polymer electrolyte fuel cell (PEFC) incorporating a Pd/C cathode was fabricated and its CO2 reduction and power generation performances were evaluated. Methane (CH4), methanol (CH3OH), and lactic acid (CH3CH(OH)COOH) were generated by CO2 reduction at minimal overpotentials, yielding Faradaic efficiencies of 14.5%, 0.29%, and 0.024%, respectively. Furthermore, the PEFC achieved a maximum power density of 0.58 mW cm−2 while concurrently reducing CO2 as a H2–CO2 fuel cell. These findings demonstrate that utilizing a Pd/C electrocatalyst can successfully transform energy-intensive CO2 conversion into a power-generating electrochemical process.