High performance of air plasma-exposed MgCo2O4 electrode material for rechargeable Mg batteries and supercapacitors

Abstract

Rechargeable magnesium batteries are attracting attention due to their high energy density, affordability, and the availability of magnesium. Among potential cathode materials, magnesium cobalt oxide (MgCo₂O₄) stands out for its promise and cost-effectiveness. This study enhances the electrochemical performance of MgCo₂O₄ nanoparticles by employing DC glow discharge plasma treatment. MgCo2O4 was synthesized using a hydrothermal process and then exposed to plasma, which altered the surface layers of the nanoparticles, improving properties such as wettability, adhesion, and surface area. Structural, morphological, and electrochemical studies revealed that the plasma-treated MgCo₂O₄ achieved a specific capacitance of 989 F/g at 0.3 mA/g and maintained a capacitive retention of around 90% over 3000 cycles, outperforming untreated MgCo₂O₄. These results highlight that the plasma treatment significantly enhances the electrochemical properties of MgCo₂O₄, making it a highly suitable material for energy storage applications in rechargeable magnesium batteries.