CuO nanorods for high-efficiency nitrate electroreduction to ammonia

Electrocatalytic nitrate reduction (NO3-RR) provides an environmentally friendly alternative to the traditional Haber-Bosch technology for ammonia (NH3) production. Herein, cupric oxide (CuO) nanorods (NRs) were synthesized by a simple one-pot method and applied as NO3-RR electrocatalysts. Due to the nanorod-like structure and large specific surface area, the CuO NR electrocatalyst exhibited excellent NO3-RR performance. The electrocatalyst experienced in situ reconstruction and its phase partly changed from CuO to Cu/Cu2O in the process of the NO3-RR. The formed Cu/Cu2O/CuO mixed valence state promoted its catalytic activity for the NO3-RR. At -0.7 V potential, the faradaic efficiency and NH3 yield could reach 94% and 28.76 mg h-1 mgcat-1, respectively, along with excellent durability for 10 h.