Synthesis of flower-like Mn-Co-MoS₂ compounds for high-performance asymmetric supercapacitors

This study aimed to intercalate manganese (Mn) and cobalt (Co) ions in molybdenum disulfide (MoS₂) to synthesize Mn-Co-MoS₂ compounds using a simple one-step hydrothermal process. Surface morphologies, material properties, and electrochemical characteristics of the synthesized Mn-MoS₂, Co-MoS₂, and Mn-Co-MoS₂ compounds were investigated. The Mn-Co-MoS₂ electrode demonstrated excellent pseudocapacitive characteristics compared to the Mn-MoS₂ and Co-MoS₂ electrodes that had a high specific capacitance of 268.7 F/g at a current density of 1 A/g, low charge transfer resistance of 10.4 Ω, and good capacitance retention of 81.2% after 5000 charge-discharge cycles at a current density of 10 A/g. The Mn-Co-MoS₂ composite and activated carbon (AC) were selected as cathode and anode electrodes for asymmetric supercapacitors, respectively. Furthermore, asymmetric Mn-Co-MoS₂//AC supercapacitors achieved good cycle stability, retention performance, specific capacitance of 24.18 F/g, discharge time of 40 s, energy density of 20.51 Wh/kg, and power density of 819.71 W/kg. Additionally, the assembled asymmetric Mn-Co-MoS₂//AC supercapacitors were used to test the green light emitting diode lights, which exhibited excellent charge storage capacity. The results confirmed that Mn-Co-MoS₂ compounds with flower-like structures had high active sites, excellent specific capacitance, and good cycle stability and were suitable for use in energy storage devices.