Efficient nitrite-glycerol paired electrolysis enabled by a MoOx-modified Cu0.81Ni0.19 alloy electrode.

Abstract

Paired electrolysis integrating the nitrite reduction reaction (NO2RR) with the glycerol oxidation reaction (GOR) offers an energy-efficient strategy for simultaneously producing value-added chemicals. Herein, we report a defect-rich amorphous MoOx cluster-decorated Cu0.81Ni0.19 alloy electrode (CuNi(MoOx)/NF) featuring a strongly coupled oxide/alloy interface as a highly efficient electrocatalyst for both NO2RR and GOR. The optimal catalyst exhibits promising performance, delivering a maximum NH3 Faradaic efficiency (FE) of 96.1% with an NH3 production rate of 1.06 mmol h-1 cm-2 for NO2RR, together with a formate FE of 96.1% and a production rate of 1.34 mg h-1 cm-2 for GOR. Operando spectroscopic characterizations combined with electrochemical analyses reveal that the interfacial MoOx species effectively accelerate reaction kinetics of both NO2RR and GOR. Consequently, the CuNi(MoOx)/NF enables energy-efficient paired electrolysis in a membrane electrode assembly, requiring only 1.47 V to reach 200 mA cm-2 while maintaining stable NH3 and formate production for over 300 h. It also exhibits outstanding performance in a rechargeable Zn-NO2- battery with a peak power density of 10.14 mW cm-2 and high cycling stability, highlighting its versatility for practical electrochemical energy conversion.