NiCo Alloy Particles Decorated on TiO2 Nanoarray as an Efficient Electrocatalyst for Nitrite Reduction to Ammonia

Abstract

Electrocatalytic nitrite (NO2−) reduction (NO2−RR) is a potential environmentally friendly method for producing NH3 efficiently. Herein, a hybrid catalyst with NiCo alloy particles uniformly decorated on TiO2 nanograss array (NiCo-TiO2) is reported to display excellent NO2−RR performance. In alkaline media, NiCo-TiO2 possesses a large NH3 yield of 18736.2 μg h−1 cm−2 at −0.4 V vs. RHE and a maximum FE of 97.5%. Utilizing NiCo-TiO2 as the cathode of the Zn-NO2− battery, it exhibits remarkable peak power density (6.49 mW cm−2) and a large NH3 yield (1911.4 g h−1 cm−2 at 20 mA cm−2). This work highlights the potential of catalysts based on alloy-metallic oxide hybrid for the electrochemical conversion of NO2− pollutant into NH3.