Ni and WC nanoparticles co-embedded in carbon nanofibers as robust bifunctional electrocatalyst for oxygen and hydrogen evolution reactions

Fabrication of high performance and low-cost nonprecious metal carbides for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is significantly important. Herein, Ni and WC (Tungsten Carbide) nanoparticles embedded in carbon nanofibers (Ni-WC/CNFs) electrocatalysts were successfully synthesized by electrospinning followed by subsequent carbonization process. The morphology and composition of the Ni-WC/CNFs composite were characterized by using SEM and XRD analysis. Ni and WC nanoparticles were successfully uniformly dispersed on carbon nanofibers (CNFs). The Ni-WC/CNFs electrocatalysts exhibit excellent electrocatalytic activity towards OER and HER in 1.0 M KOH solutions. The experimental results show that the OER and HER overpotentials of Ni-WC/CNFs are 350 mV and 190 mV respectively when the current density is 10 mA cm⁻². The excellent electrocatalytic properties of OER and HER are attributed to the synergistic effect between Ni and WC nanoparticles and the large electrochemically active surface area. This study provides a simple and feasible strategy for the development of bifunctional electrocatalysts with low cost and high activity.