Spin-Selective Anti-Perovskite Enables Breakthrough Nitrate-to-Ammonia Electrocatalysis

Abstract

Electrochemical nitrate reduction to ammonia offers environmental and energy benefits, but progress is hindered by sluggish multistep proton-coupled electron transfers and competing side reactions. Here, we introduce an antiperovskite CuNCo3 catalyst featuring a 3d–3d interaction framework. This framework stabilizes spin-selective Co sites even upon surface Co-N bond cleavage and drives asymmetric nitrate consumption. CuNCo3 achieves 100% Faradaic efficiency and an NH3 production rate of 124.6 mg mgcat−1 h−1 at −0.4 V vs. RHE. Operando XAS, XES, and ATR-FTIR directly link the evolution of spin-selective Co sites with specific NO3RR intermediates, revealing that spin-selective Co sites lower hydrogenation barriers and accelerate key steps. These results demonstrate that spin-selective anti-perovskite frameworks provide a robust, earth-abundant platform for high-performance nitrate-to-ammonia electrocatalysts.