Metal organic framework derived vanadium nitride anchored on nitrogen-doped carbon sheet as an efficient electrocatalyst for nitrogen reduction reaction

Abstract

A metal organic framework-assisted annealing and nitriding method is employed to prepare a heterostructured nanocomposite incorporating VN nanoparticles with nitrogen-doped carbonaceous sheets as an earth-abundant catalyst of electrochemical nitrogen reduction reaction (ENRR). In this as-synthesized nanocomposite (VN@NC), nanosized VN particles with diameter of ∼50 nm are in situ fabricated and are anchored on the metal organic frameworks-derived nitrogen-doped carbon sheets. Benefitting from its structural merits such as increased surface areas, abundant active sites, improved electroconductivity as well as the synergism between the components, the composite electrocatalyst exhibits a greatly enhanced catalytic activity for ENRR in comparison with the commercial bulk VN. The as-prepared VN@NC can catalyze nitrogen to yield ammonia with a rate up to 17.31 μg mg−1cat h−1 at a low potential (-0.2 V vs RHE) in 0.1 M hydrochloric acid solution under mild conditions, delivering a Faradaic efficiency of 10.99 % simultaneously. Furthermore, VN@NC also demonstrates a favourable selectivity without generation of hydrazine byproduct and a stable electrocatalytic performance.