Pt‐Regulated Dynamic Cu(0) Regeneration in CuPt Alloy Enables High‐Efficiency Self‐Driven Formaldehyde Fuel Cells for Potassium Formate Production

Efficient and clean conversion of carbon‐based molecular fuels into electricity without CO 2 emission remains a great challenge. Herein, formaldehyde was employed as a novel fuel catalyzed by a Cu 30 Pt X /CF anode, which was fabricated via electrodeposition. The electronic interaction between Pt and Cu boosts H * dimerization into H 2 (the rate‐determining step), facilitates the desorption of formic acid, and promotes the regeneration of Cu 0 active sites, thus enhancing the catalytic activity and stability and broadening the potential window for formaldehyde oxidation. Furthermore, a direct formaldehyde fuel cell was constructed, in which the one‐electron oxidation of formaldehyde proceeds with high selectivity on the Cu anode without the CO 2 formation pathway. This fuel cell delivers an open‐circuit voltage of 0.94 V and a peak power density of 34.3 mW cm −2 , and enables the highly selective production of potassium formate while generating electricity spontaneously with a Faradaic efficiency approaching 100%. This work realizes the co‐generation of electrical energy and high‐value‐added chemicals, providing a new strategy and mechanistic basis for the design of high‐performance direct formaldehyde fuel cells (DFFC).