Ni@TiO2 Nanoarray with the Schottky Junction for the Highly Selective Electrochemical Reduction of Nitrite to Ammonia

Electrocatalytic reduction of nitrite (NO2-) is of vital significance for the removal of NO2- pollution and simultaneously making value-added ammonia (NH3). Herein, Ni nanoparticles anchored on the TiO2 nanoribbon array with the Schottky junction were successfully constructed for highly selective NO2- reduction to NH3. Density functional theory reveals the construction of the Ni@TiO2 Schottky junction leads to charge rearrangement and optimized adsorptive energy of intermediates, assuring the selective conversion from NO2- to NH3. Expectantly, this catalyst achieves an impressive NH3 yield of 568.7 mu mol h-1 cm-2 and an ultrahigh Faradaic efficiency of 98.5% under ambient conditions with good stability.