H2-CO2 polymer electrolyte fuel cell that generates power while evolving CH4 at the Pt0.8Ru0.2/C cathode

Abstract

Generating electric power using CO2 as a reactant is challenging because the electroreduction of CO2 usually requires a large overpotential. Herein, we report the design and development of a polymer electrolyte fuel cell driven by feeding H2 and CO2 to the anode (Pt/C) and cathode (Pt0.8Ru0.2/C), respectively, based on their theoretical electrode potentials. Pt–Ru/C is a promising electrocatalysts for CO2 reduction at a low overpotential; consequently, CH4 is continuously produced through CO2 reduction with an enhanced faradaic efficiency (18.2%) and without an overpotential (at 0.20 V vs. RHE) was achieved when dilute CO2 is fed at a cell temperature of 40 °C. Significantly, the cell generated electric power (0.14 mW cm−2) while simultaneously yielding CH4 at 86.3 μmol g−1 h−1. These results show that a H2-CO2 fuel cell is a promising technology for promoting the carbon capture and utilization (CCU) strategy.