Laser-engineered AuPt@Cu heterointerfaces for highly efficient electrocatalytic nitrite-to-ammonia conversion and Zn-nitrite batteries

초록

Nitrite (NO2−) contamination poses significant environmental and health risks, necessitating efficient remediation strategies that also enable value-added chemical production. Herein, we report laser-assisted synthesis of AuPt alloy–decorated Cu (AuPt@Cu) microspheres via pulsed laser irradiation in liquid, a rapid, surfactant-free method. Systematic optimization of AuPt loading on Cu identified AuPt@Cu-4 exhibits superior electrocatalytic NO2− reduction reaction (eNO2RR) in alkaline media, achieving a maximum NH3 yield rate of 18.02 mg h−1 cm−2 and a Faradaic efficiency of 91.2% at a potential of −0.4 V vs. reversible hydrogen electrode (RHE) in 1 M KOH with 0.1 M KNO2 electrolyte, surpassing benchmark catalysts via synergistic AuPt@Cu electronic modulation that enhances the binding energy between the active sites and the nitrogenous intermediates. In situ Raman spectroscopy and ex situ Fourier transform infrared spectroscopy were employed to identify reaction intermediates, corroborating the findings of density functional theory calculations. Assembly of a Zn–NO2− battery using an AuPt@Cu-4 cathode and Zn anode delivered an open-circuit voltage of 1.29 V with a power density of 4.1 mW cm−2 at a current density of 10 mA cm−2, and exhibited robust stability over 100 h. This study advances scalable electrocatalytic platforms for NO2− valorization, coupling pollutant remediation with sustainable NH3 production and energy harvesting. © 2026 Elsevier B.V.

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