SiC embedded in coral-shaped Ni-Co-P nanohybrids for enhanced overall water electrolysis performance

Abstract

In this work, we prepared nano SiC embedded Ni-Co-P nanohybrid (NCP-SiC) by one-step composite electrodeposition on nickel foam. Meanwhile, we evaluated their enhanced electrocatalytic performance toward hydrogen and oxygen evolution reaction (HER and OER) and overall water splitting in an alkaline aqueous solution compared with NCP. The studies show the NCP-SiC nanohybrid electrocatalysts composed of bimetallic Ni-Co/Ni₂P/CoP nanohybrid encapsulating nano SiC, taking a coral shape, which has an overpotential of only 71 mV at a current density of 10 mA/cm² and a Tafel slope of 32.5 mV/dec. Moreover, NCP-SiC electrocatalysts possess bifunctional catalytic characteristics with an overall water-separation overpotential of only 1.57 V. These excellent electrocatalytic performances result from the incorporating effect of the nano SiC with the Ni-Co-P nanohybrids that own unique morphology and structure features. The resulting heterostructures accelerated the electron transfer, increased the active sites on the surface, and reduced the required activation energy, which leads to improved electrocatalytic activity. This work provides a workable strategy for semiconductor materials in improving total hydrolysis for hydrogen production applications.