Mechanism of synthesis ammonia over atomically dispersed Ni/BCN catalyst under atmospheric pressure and low-temperature conditions

In industry, ammonia synthesis process typically requires high temperatures (400 - 500 degrees C) and high pressures (20 - 40 MPa), resulting in high energy consumption and high carbon emissions. Exploring the direct ammonia synthesis with N 2 and H 2 under mild conditions without the assistance of electrochemical or photochemical energy, represents a promising approach. In this study, atomically dispersed Ni loaded on B-doped CN catalyst (Ni/BCN) was prepared by a liquid phase one-pot method, which achieved efficient ammonia synthesis under mild conditions of 101.3 kPa and 80 degrees C, with an ammonia yield of 114 mu mol h -1 g cat -1 after 10 h. Further experimental studies combined with the characterization of catalyst morphology, bulk phase structure, and surface chemical state reveal the mechanism of ammonia synthesis under mild conditions. The appearance of nitrogen vacancies on Ni/BCN can promote the electron delocalization of stable N equivalent to N bonds in N 2 , facilitating the activation of N 2 . B, C and N bond with each other to form a hybrid BCN carrier, which promotes the electron transfer on the surface. Our findings suggest a general approach to engineer catalysts that can drive critical reactions pertinent to energy conservation, low-carbon, and sustainability.