Enhancement of OER activity by incorporating nickel nanoparticles into Co-MoS₂ composite electrodes and with the assistance of a magnetic field

Abstract In this study, we developed a cobalt-based composite electrode with enhanced oxygen evolution reaction (OER) performance by incorporating MoS 2 microparticles and nickel nanoparticles during electrode fabrication. Importantly, an external magnetic field was applied during the electrode preparation process, which contributed to improved microstructure and increased surface area of the resulting composite electrode. The pure Co electrode exhibited limited OER activity, which was significantly improved by the addition of MoS 2 to form a Co-MoS 2 composite. Further enhancement was achieved by doping with nickel nanoparticles, and the combination of these components with magnetic-field-assisted synthesis led to a dense distribution of active sites. The optimized Ni-Co-MoS 2 composite electrode exhibited excellent OER performance, with an overpotential of 275 mV at 10 mA·cm −2 when prepared under a magnetic field strength of 80 mT. The improved catalytic activity is attributed to the synergistic effects of MoS 2 and Ni nanoparticles, as well as the magnetic field-induced modification of electrode microstructure during synthesis.