Hierarchical nickel-vanadium nanohybrid with strong electron transfer for accelerated hydrogen evolution reaction

Abstract

Rational design of non-precious materials with high-performanced and stable electrocatalytic activity for hydrogen evolution reaction (HER) is vital for the wide application of renewable energy device. In this work, we successfully fabricated a binder-free catalyst comprising Ni and V2O3 grown on Ni foam (NF) via annealing hydrothermally resultant Ni3V2O8/NF in a H2/Ar atmosphere and applied it as a non-precious HER electrocatalyst. The as-fabricated material denoted as Ni@V2O3/NF behaves with a unique structure in form of Ni nanoparticles wrapped by V2O3, which should be attributed to the rolling up of nanosheet caused by the Ni outward diffusion from Ni3V2O8 nanosheet during the pyrolysis process. Moreover, the oxygen vacancies-rich V2O3 can donate electron to the in-situ formed Ni nanoparticles and restrict their overgrowth, which regulate the electronic structure of nanohybrid, facilitate HER kinetic process and create abundant accessible active sites. Hence, the Ni@V2O3/NF demonstrates superior HER activity delivering current density of 10 mA cm−2 at an appropriate overpotenial of 19 mV with a low Tafel slope of 48.5 mV/dec and long-term stability in alkaline solution. This work will provide inspirations to the exploration of Ni-V based electrocatalysts for various emerging energy applications.