NiMoO4 nanorods with oxygen vacancies self-supported on Ni foam towards high-efficiency electrocatalytic conversion of nitrite to ammonia

Abstract

As an eco-friendly and sustainable strategy, the electrochemical reduction of nitrite (NO2–) can simultaneous generation of NH3 and treatment of NO2– contamination in the environment. Herein, monoclinic NiMoO4 nanorods with abundant oxygen vacancies self-supported on Ni foam (NiMoO4/NF) are considered high-performance electrocatalysts for ambient NH3 synthesis by reduction of NO2−, which can deliver an outstanding yield of 18089.39 ± 227.98 μg h−1 cm−2 and a preferable FE of 94.49 ± 0.42% at −0.8 V. Additionally, its performance remains relatively stable during long-term operation as well as cycling tests. Furthermore, density functional theory calculations unveil the vital role of oxygen vacancies in promoting nitrite adsorption and activation, ensuring efficient NO2–RR towards NH3. A Zn-NO2– battery with NiMoO4/NF as the cathode shows high battery performance as well.