Co-valorization of plastic and battery waste into a borate-engineered NiCo catalyst for urea-assisted hydrogen production

Urea-assisted water electrolysis provides an energy-efficient route for hydrogen production and wastewater treatment, yet current electrode fabrication often incurs high economic and environmental costs. Here, we present a circular co-valorization strategy that converts metal-rich battery effluents and plastic waste into a borate-engineered NiCo layered double hydroxide supported on plastic-waste-derived carbon (NiCo LDH-B/PWC). The resulting catalyst delivers 10 mA cm −2 for urea oxidation at 1.31 V vs. the reversible hydrogen electrode (RHE). Mechanistic analyses reveal that borate enhances the catalytic activity of the in - situ -generated NiCo oxyhydroxide by promoting electronic delocalization, optimizing orbital alignment, and lowering reaction energy barriers. In urine-wastewater electrolysis, the NiCo LDH-B/PWC || Pt/C system operates stably for 48 h with ∼98% Faradaic efficiency for hydrogen production while achieving a low electrode fabrication cost of $1.33 m −2 . This work highlights the potential of co-valorizing heterogeneous waste streams for sustainable hydrogen generation and integrated pollution mitigation.