Durable Natural Urine Electrolysis Enabled by Lewis Acid‐Tailored Interfacial Microenvironment

Abstract

Abstract Electrochemical urea oxidation reaction (UOR) is a promising alternative to sluggish oxygen evolution reaction (OER) for hydrogen production. However, its reliance on costly pure urea limits practical application. To address this issue, urine oxidation reaction (U r OR) has been proposed, which utilizes natural urine as a cost‐free feedstock. Nevertheless, due to the complex ionic matrix of urine, U r OR suffers from catalyst acidification and chloride‐induced corrosion, limiting long‐term stability. Here, an interfacial microenvironment regulation strategy by modifying common Ni 2 P catalyst with various hard Lewis acids (LA) is reported. The optimal V 2 O 5‐δ ‐Ni 2 P hybrid exhibits remarkable U r OR activity (1.62 V at 3 A cm −2 ) and long‐term durability (1000 h). Mechanistic analysis reveals that LA component selectively enriches interfacial OH − ions, effectively suppressing the adsorption of impurities, especially Cl − ions, and the generation of N‐chlorourea byproduct. Notably, a near‐kilowatt‐scale natural urine electrolysis is first verified in a flow electrolyser (18 cells, area of 1386 cm 2 ), achieving a high H 2 production rate of 115.84 L h −1 with a urine purification rate of 97.41%, while recovering nitrogen‐rich compound fertilizers (NH 4 Cl/KCl). Furthermore, the electrolyzer exhibits broad applicability across wastewater with various urea concentrations (5–330 mM) and Cl − ions concentrations (0.5‐500 mM), including challenging 100 L wheatfield effluents.