Hydrogen Evolution Reaction by Gd-Doped Transition Metal Dichalcogenide VSe2 Nanoflowers

Abstract

The renewable energy source, such as hydrogen, is helpful in reducing the dependence on fossil fuels. Electrocatalytic water splitting produces hydrogen, which is a cleaner and more reliable energy source than fossil fuels. The number of exposed active sites in a catalyst considerably affects its catalytic activity. Recently, transition metal dichalcogenides have been widely investigated for electrochemical performance. In this context, we have prepared Gd-doped VSe2 nano composites V1-xGdxSe2 (x= 0, 0.2, 0.3) by using a simple and inexpensive hydrothermal method for catalytic Hydrogen evolution reaction (HER). The nano flower-like surface morphology possessed by the prepared sample with an increase in bandgap from 2.6 to 3.6 eV by Gd doping. The higher Gd-doping sample shows significantly better electrochemical characterizations than the pure VSe2 sample. The higher Gd-doped sample shows higher electrochemical performances with an onset potential around 210 mV, and a low value of the Tafel plot of around 60 mV/decade with respect to other samples. The sample also shows a low charge transfer resistance value of around 1.30 kΩ, calculated from impedance data, which shows good agreement with the HER polarization and Tafel plot.

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