ABSTRACT Substituting the kinetically sluggish oxygen evolution reaction with the thermodynamically favorable urea oxidation reaction (UOR) offers a compelling strategy for simultaneously achieving energy‐efficient hydrogen production and wastewater remediation. Nevertheless, the design of UOR catalysts that combine high activity with long‐term durability remains a significant challenge. Herein, we report the scalable fabrication of binder‐free Ni–W nanostructures directly grown on carbon paper through a controlled potentiostatic electrodeposition approach. Electrochemical kinetic analysis confirms that the electrocrystallization follows a diffusion‐controlled pathway characterized by instantaneous nucleation and subsequent three‐dimensional growth. The optimized Ni–W electrode delivers outstanding UOR activity, reaching a current density of 100 mA cm −2 at a potential of just 1.77 V versus the reversible hydrogen electrode. In a two‐electrode urea electrolyzer configuration, the system achieves 10 mA cm −2 at only 1.54 V, markedly lower than the voltage required for conventional water splitting. Beyond the energy‐efficient hydrogen generation, the system demonstrates meaningful environmental remediation capability, degrading 47% of urea over 30 h of continuous electrolysis. By integrating pollutant removal with electrolytic H 2 production within a single platform, this work establishes a scalable, binder‐free catalyst architecture aligned with circular economy principles and advances the frontier of sustainable energy conversion. image
Zeng et al. (Mon,) studied this question.