Efficient nitrite-to-ammonia electroreduction over Zr-Ni frustrated Lewis acid-base pairs

Electrochemical NO₂⁻-to-NH₃ conversion (NO₂RR) offers a green route to NH₃ electrosynthesis, while developing efficient NO₂RR catalysis systems at high current densities remains a grand challenge. Herein, we report an efficient Zr-NiO catalyst with atomically dispersed Zr-dopants incorporated in NiO lattice, delivering the exceptional NO₂RR performance with industrial-level current density (>0.2 A cm⁻²). In situ spectroscopic measurements and theoretical simulations reveal the construction of Zr-Ni frustrated Lewis acid-base pairs (FLPs) on Zr-NiO, which can substantially increase the number of absorbed nitrite (NO₂⁻), promote the activation and protonation of NO₂⁻ and concurrently hamper the H coverage, boosting the activity and selectivity of Zr-NiO towards the NO₂RR. Remarkably, Zr-NiO exhibits the exceptional performance in a flow cell with high Faradaic efficiency for NH₃ of 94.0% and NH₃ yield rate of 1,394.1 µmol h⁻¹ cm⁻² at an industrial-level current density of 228.2 mA cm⁻², placing it among the best NO₂RR electrocatalysts for NH₃ production.