Sn‐Doped Black Phosphorene for Enhancing the Selectivity of Nitrogen Electroreduction to Ammonia

Abstract The electrocatalytic nitrogen reduction reaction (NRR) to ammonia (NH 3 ) is a highly desirable yet challenging objective because of the competing hydrogen evolution reaction (HER). Herein, a novel electrocatalyst of Sn‐doped black phosphorene (Sn‐BP ene ) is demonstrated with dramatically improved selectivity for the NRR. The Sn that is added acts as a sacrificial species for the HER to protect the NRR active sites on black phosphorene (BP ene ). The Sn‐BP ene achieves a Faraday efficiency of up to 36.51% and a prominent NH 3 yield rate of 26.98 µg h –1 mg cat –1 at a relatively low overpotential. Density functional theory calculations prove that the adsorption sites of H 2 O and N 2 are separated after doping with Sn, with H 2 O adsorbing preferentially onto the Sn sites and N 2 onto the NRR active sites of BP ene , leading to high selectivity.