Structural optimization of oxygen vacancies in WO3 by Cu doping for enhanced electrocatalytic nitrate reduction to ammonia

Copper introduction optimized oxygen vacancies in WO 3 . The synergistic effect of Cu doping and O v enhanced the NO 3 RR performance. Cu–WO 3 achieved the highest NH 3 yield of 2131.3 μg h −1 mg cat −1 and FE of 94% at −0.6 V ( vs. RHE).