Electrocatalytic Performance of Micro–Nano-Nickel Electrodes via Magnetic Field-Assisted Jet Electrodeposition Method

Abstract

Hydrogen production from water electrolysis using transition metal-based catalysts is a hot research topic at present, and the oxygen evolution reaction (OER) will directly affect the efficiency of water electrolysis. In this work, nickel metal electrodes with micro−nanostructures were rapidly prepared on the surface of a stainless steel substrate by magnetic field-assisted jet electrodeposition (MAJE) and the OER performance of the micro−nanonickel electrode in electrolytic water was mainly studied. By adding magnetic nano-nickel particles to the electrolyte, the nano-nickel particles reached the electrode surface and were firmly adsorbed by the magnetic field with the flow of the electrolyte. The results showed that the surface morphologies and the preferred growth orientation of nickel electrodes changed in MAJE. In MAJE, when the amount of nano-nickel particles was 2 g/L, the micro−nano-nickel electrode exhibited excellent OER catalytic performance with an overpotential of 274 mV at a current density of 10 mA•cm −2 and a lower Tafel slope of 33.2 mV dec −1 under alkaline conditions. This study confirmed that MAJE had certain advantages in the preparation of metal-based catalytic electrodes, which provided an idea for the research of catalytic electrodes for hydrogen production by electrolysis of water.

Magnetic Field-Assisted Electrodeposition of Fe3O4 Nanoparticles on Ni as Bifunctional Electrocatalyst for Overall Water Splitting

“…Figure shows the surface morphology of the Ni electrode under different auxiliary magnetic fields before and after the addition of Fe 3 O 4 nanoparticles. From the scanning electron microscopy (SEM) image (Figure b), it can be seen that the surface of the Ni electrode without the addition of a magnetic field has a smoother surface relative to the Ni electrode assisted by a single magnetic field (Figure a), and there are no protruding crystals, similar to the current research . The surface morphology of the Ni/Fe 3 O 4 electrode under the influence of the magnetic field is shown in Figure c and d, which is rougher as compared to the Ni electrode without the addition of a magnetic field with nanoparticles.…”