CuO/Mn2O3 heterojunction for efficient electrochemical nitrate reduction to ammonia

Abstract

A CuO/Mn₂O₃ heterojunction catalyst is successfully prepared by a simple hydrothermal and calcination method, which exhibits a unique spindle-like morphology with a rough surface that can expose more active sites. Moreover, the formation of a heterogeneous interface accelerates the interfacial electron transfer, and optimizes the desorption and hydrogenation process of CuO/Mn₂O₃ to intermediates, significantly enhancing the NO₃RR activity. Thus, CuO/Mn₂O₃ exhibits a high NH₃ Faradaic efficiency of 98.44%, and a high NH₃ yield of 12 990.49 μg h⁻¹ cm⁻² at −0.7 V vs. RHE in alkaline medium.