TiB2 thin film enabled efficient NH3 electrosynthesis at ambient conditions

Electrocatalytic N 2 reduction is regarded as an attractive alternative to the industrial Haber-Bosch process for mild NH 3 synthesis. However, its practical feasibility requires efficient electrocatalysts with high activity and selectivity . Herein, we first report using sputtered TiB 2 film to enable superb artificial N 2 reduction electrocatalysis . In 0.1 M HCl, such TiB 2 seizes a great NH 3 yield of 1.75 × 10 −10  mol s −1 cm −2 and a high Faradaic efficiency of 11.37% at −0.30 V vs. reversible hydrogen electrode with excellent durability. Density functional theory calculations further evidence that the high activity and selectivity of TiB 2 arise from the positively charged Ti atomic plane, which facilitates the adsorption, activation, and hydrogenation of N 2 molecules while well suppresses the binding of H atoms.