Synthesis and characterization of CoMn2O4 spinel onto flexible stainless-steel mesh for supercapacitor application
Souha Aouini, Afrah Bardaoui, A.M. Botelho do Rego, Ana M. Ferraria, Diogo M.F. Santos, R. Chtourou
Abstract
CoMn2O4 spinel was synthesized on stainless steel mesh through a hydrothermal process, controlling the reaction time (6 h, 12 h, 18 h, and 24 h). Characterization techniques included XRD, ATR-FTIR, XPS, and SEM-EDS. The 24-h reaction time led to CoMn2O4 spinel with the desired structure, stoichiometry, and good crystallinity. The sample exhibited a tetragonal structure, with Co–O and Mn–O vibrational bands, and manganese (Mn3+) and cobalt (Co2+) metal oxides on the surface. It had a sheet-like shape with an average particle size of 1.92 ± 0.28 μm. Electrochemical tests showed high CV-specific capacitance of 1014.15 F g−1 at 1 mV s−1 and 764.84 F g−1 at 5 mV s−1, aligned with GCD-specific capacitance at 5 A g−1 (724.61 F g−1) and a charge-transfer resistance of 7.71 Ω. The synthesized electrode holds promise for practical energy storage devices, namely for supercapacitor applications.