Cr3C2 Nanoparticle-Embedded Carbon Nanofiber for Artificial Synthesis of NH3 through N2 Fixation under Ambient Conditions.

Industrial production of NH3 heavily depends on the conventional Haber-Bosch process under rigorous conditions with a large amount of energy consumption and carbon emissions. Electrocatalysis exhibits an intriguing prospect for the N2 reduction reaction (NRR) at ambient conditions. In this case, a high-efficiency and low-cost catalyst is paramount. In this letter, Cr3C2 nanoparticles and carbon nanofiber composite (Cr3C2@CNF) are proposed as a noble-metal-free NRR electrocatalyst for converting N2 to NH3 with an excellent selectivity. The optimal Faradic efficiency and NH3 yield rate achieved are as high as 8.6% and 23.9 μg h-1 mgcat.-1 at -0.3 V vs reversible hydrogen electrode in 0.1 M HCl, respectively. Theoretical calculations show a low reaction barrier of merely 0.53 eV in the enzymatic route for this catalyst.