Tungsten-inert gas welding electrodes as low-cost, green and pH-universal electrocatalysts for hydrogen evolution reaction

Large-scale electrolytic production of hydrogen, as the most important energy carrier, requires low-cost and easily available electrocatalysts. Herein, different tungsten-inert gas (TIG) welding electrodes, namely, pure tungsten (W), zirconiated tungsten (W-Zr), ceriated tungsten (W-Ce) and lanthanated tungsten (W-La) electrodes, are introduced as low-cost, green and pH-universal electrocatalysts for the hydrogen evolution reaction (HER). The morphology, microstructure and composition of these electrodes have been investigated using field emission scanning electron microscope (FE-SEM), energy dispersive X-ray (EDX) and elemental mapping. The electrocatalytic activity of the electrodes have been studied under acidic, basic and neutral conditions using linear sweep voltammetry (LSV), open circuit potential (OCP) measurments and electrochemical impedance spectroscopy (EIS) and the values of onset potential (Eonset), overpotential at 10 mA cm-2 (η10), Tafel slope, OCP and charge transfer resistance (Rct) have been obtained for each electrode under acidic, basic and neutral conditions. It can be claimed that among all the studied electrodes, the W-La electrode shows the best electrocatalytic performance according to the values of Eonset, η10, OCP, and Rct.