Electrocatalytic performance of nickel coating on carbon felt with silver particles inclusions

Abstract

BackgroundThe synthesis of nanocomposite as an effective electrocatalyst for the hydrogen evolution reaction (HER) was the purpose of this research. The Ni-Ag binary system was selected as the solution, combining the electrocatalytic properties of nickel and the high electrical conductivity of silver. To lower the use of metal, synthesis was carried out on carbon fibers. MethodsThe electrodeposition method was used for the synthesis. Nanocomposites were analyzed using scanning electron microscopy (SEM), X-ray diffraction, voltammetry, chronopotentiometry and electrochemical impedance spectroscopy. Significant findingsNi/Ag-CF and Ni/Ag-CF(t) composites with an average crystallite size of 24 and 33 nm (for Ag) and 22 and 23 nm (for Ni), respectively, were obtained. The SEM images confirm the formation of a mesh frame (like Turing patterns) during the heat treatment of the Ag-CF precursor, which reduces the impedance of nanocomposite from 15.6 to 6.7 Ohms. Studies of electrocatalytic properties demonstrate a decrease in the overpotential of HER from -210 to -80 mV with an increase in the exchange current density (logarithm value from -5 to -2.5) in comparison with Ni-CF without silver particles.