Efficient electrocatalytic reduction of nitrate to ammonia over fibrous SmCoO₃ under ambient conditions

We report SmCoO₃ nanofibers as an efficient catalyst for nitrate reduction to ammonia. This catalyst achieves a large NH₃ yield of 14.4 mg h⁻¹ mg_cat.⁻¹ and a high faradaic efficiency of 81.3% at −1.0 V vs. RHE in 0.1 M PBS with 0.1 M NaNO₃, and it also displays excellent electrochemical durability and structural stability. Theoretical calculations indicate that Sm–O and Co–O bonds have an incredibly low adsorption energy of −0.1 eV, which can significantly reduce the applied potential and hence enhance the catalytic activity.