A Direct Formaldehyde Fuel Cell for CO₂‐Emission Free Co‐generation of Electrical Energy and Valuable Chemical/Hydrogen

Converting carbon‐based molecular fuels into electricity efficiently and cleanly without emitting CO 2 remains a challenge. Conventional fuel cells using noble metals as anode catalysts often suffer performance degradation due to CO poisoning and a host of problems associated with CO 2 production. This study provides a CO 2 ‐emission‐free direct formaldehyde fuel cell. It enables a flow of electricity while producing H 2 and valuable formate. Unlike conventional carbon‐based molecules electrooxidation, formaldehyde 1‐electron oxidation is performed on the Cu anode with high selectivity, thus generating formate and H 2 without undergoing CO 2 pathway. In addition, the fuel cell produces 0.62 Nm 3 H 2 and 53 mol formate per 1 kWh of electricity generated, with an open circuit voltage of up to 1 V and a peak power density of 350 mW cm −2 . This study puts forward a zero‐carbon solution for the efficient utilization of carbon‐based molecule fuels that generates electricity, hydrogen and valuable chemicals in synchronization.