Self‐Powered System for H₂ Production and Biomass Upgrading

Hydrazine‐oxidation‐assisted self‐powered H 2 generation system greatly expands the applicability of hydrogen production technology. However, the high cost of hydrazine greatly impedes the widespread adoption of hydrazine‐contained energy systems for large‐scale H 2 production. Besides, the gaseous products of hydrazine splitting, comprising a mixture of H 2 and N 2 , necessitate energy‐intensive downstream separation. Here, taking advantage of a low‐potential furfural oxidation reaction (FOR) on the Cu electrode, a self‐powered H 2 production system by integrating a direct furfural fuel cell (DFFC) and a bipolar H 2 production electrolyser is reported. Ru‐dispersed Cu nanowire with remarkable catalytic activity is developed as a hydrogen evolution reaction (HER) catalyst to couple with the FOR. The HER‐FOR electrolyzer achieves bipolar H 2 production with an apparent 200% Faradaic efficiency, attaining a current density of 100 mA cm −2 with a low cell voltage of 0.43 V. The DFFC displays an open circuit potential of 0.969 V and a peak power density up to 193 mW cm −2 . Inspired by the bipolar H 2 production that eliminates the gas separation, a self‐powered system utilizing furfural as the sole consumable, which yields a pure H 2 production rate of 6 mmol h −1 m −2 is demonstrated. This work provides a new avenue for constructing self‐powered H 2 production systems.