[Abstract]

Ammonia production from electrocatalytic nitrate reduction reaction (NO₃RR) is a significant research field to potentially substitute the Haber-Bosch process. However, low ammonia selectivity due to competitive hydrogen evolution reaction is an issue for the NO₃RR. In this study, a series of manganese copper oxide (MnCuO_x) catalysts with different concentrations of oxygen vacancies have been prepared via Ar or O₂ plasma treatments. MnCuO_x-H with high concentration of oxygen vacancies showed a high NH₃ yield rate of 9.4 mg cm^-2h^-1 and Faradaic efficiency of 86.4 %. The high performance of MnCuO_x-H for the NO₃RR can be resulted from the feature that the more oxygen vacancies formed from the plasma treatment could facilitate adsorption and weakening N-O bonds of NO₃. This strategy suggests a novel guidance to the catalyst design for NO₃RR, which requires great improvements in terms of NH₃ selectivity and production rate.

DOI: 10.1016/j.apsusc.2022.155521

Link: https://www.sciencedirect.com/science/article/pii/S0169433222030495?via%3Dihub