Electrodeposited Nickel Sulfide Nanoparticles Incorporated Carbon Nanofibers as Effective Non-Precious Catalyst for Methanol Electrooxidation in Alkaline Medium

For direct methanol fuel cells, developing low-cost, highly efficient, and long-term stable electrocatalysts is crucial. In this work, we report easy and single-step electrodeposition of nickel sulfide thin film incorporating carbon nanofibers on indium tin oxide (denoted as Ni4S3-CNF/ITO). The electrodeposited materials were characterized by X-ray Diffraction, Scanning Electron Microscopy, and Energy Dispersive X-ray spectroscopy. The electrocatalytic activity toward Methanol Oxidation Reaction (MOR) was investigated using Cyclic Voltammetry, Chrono-Amperometry, and Electrochemical Impedance Spectroscopy. The electrocatalyst exhibited good electrocatalytic activity regarding methanol electrooxidation in an alkaline medium with retention of its activity over a significant period of time. These results indicate that the incorporation of carbon nanofibers into nickel sulfide allows the electrocatalyst to gain higher surface area and high tolerance to the catalyst-poising species generated during MOR. The electrocatalytic activity of electrodeposited Ni4S3-CNF/ITO makes it a promising electrocatalyst for low-cost, high-efficient fuel cells.