ZnFe₂O₄ nanosheet array: a highly efficient electrocatalyst for ambient ammonia production via nitrite reduction

Electrocatalytic reduction of nitrite (NO2-) offers an eco-friendly and sustainable strategy for synthesizing valuable ammonia (NH3) while simultaneously removing NO2-. Nevertheless, the complexity of the six-electron transfer reaction involved can hamper NH3 production and faradaic efficiency (FE), necessitating the quest for high-performance electrocatalysts. In this study, we introduce ZnFe2O4 nanosheet arrays on nickel foam (ZnFe2O4/NF) as an efficient electrocatalyst for the reduction of NO2- to NH3. ZnFe2O4/NF demonstrates an impressive NH3 yield of 588.58 mu mol h(-1) cm(-2) and a remarkable FE of 95.7% at -0.6 V in 0.1 M NaOH containing 0.1 M NO2-. Furthermore, it exhibits robust stability and durability throughout extended electrolysis and continuous cycling tests.