Dispersed Nickel on Gallium Liquid Metal for Nitrate Reduction to Ammonia

The pursuit of novel catalysts for efficient green ammonia production has sparked immense research endeavors. Liquid metal alloys featuring atomically dispersed active sites have emerged as a particularly promising class of catalysts. Here, we report a liquid metal alloy catalyst featuring highly dispersed nickel atoms embedded within a gallium matrix. This Ni–Ga alloy exhibits outstanding electrocatalytic activity for nitrate reduction to ammonia (NO ₃ RR), achieving a Faradaic efficiency exceeding 99% at −0.18 V versus reversible hydrogen electrode (RHE) in alkaline conditions (pH = 13). The reaction mechanism has been fundamentally investigated using density functional theory, confirming that the Ni sites on the Ni–Ga alloy surface promote an enhanced reaction pathway. Remarkably, the catalyst demonstrates spontaneous nitrate‐to‐ammonia activity and exhibits potential for long‐term operational stability.