Testing and Assessment of Various Catalysts for Uniquely Designed Cathodes for Hydrogen Evolution Reactions

Abstract

This study reports the electrodeposition of unique catalysts for 3D-printed cathodes for alkaline water electrolysis. This paper explores hydrogen evolution reaction performance for various nickel, nickel-copper, nickel-iron, and nickel-molybdenum 3D-printed electrodes. In particular, this study reports a novel electrodeposition of nickel-iron and nickel-molybdenum on conductive PLA 3D-printed electrode surfaces. The performance of the electrodes is assessed through electrochemical models including cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS). The results of the study show considerable differences, at a particular current density of 10 mA/cm2, nickel-iron, and nickel-copper coated 3D-printed electrodes are found to have an overpotential of 270 mV and 275 mV respectively. The nickel-copper and nickel-iron coated electrodes also showed to have a low resistance. The amount of metal deposited also showed to have an important role. At a potential of -2.5V, nickel coated electrode Ni4x with four times the nickel mass deposition (0.178 g/cm2) of another nickel coated electrode Ni1x (0.044 g/cm2) is found to have a current density of -106 mA/cm2 in comparison to -44 mA/cm2 respectively. These findings provide important insights for optimizing additive manufacturing for electrochemical systems.