Synthesis and characterization of metal chalcogenide modified graphene oxide sandwiched manganese oxide nanofibers on nickel foam electrodes for high performance supercapacitor applications

Nanoparticles of metal chalcogenide (MoS₂) are incorporated on reduced graphene oxide nano sheet rolled mesoporous manganese oxide were prepared by feasible ultrasonic assisted deposition technique. The above prepared nanocomposite is further coated on Nickel foam substrate for direct application towards high performance supercapcitor energy storage application. The detailed studies of surface and textural property such as crystalline phase stability, surface structure, particle size, zeta potential measurements have been explained for all prepared nanocomposite samples. The crystalline phase of as prepared mesoporous manganese oxide is forms the mixed phase of Mn₂O₃ bixbyite phase. The thermal stability of as prepared sample improved up to 400 °C in oxygen atmosphere and negative zeta potential obtained for all prepared nanocomposite sample. The different amount of MoS₂ nanoparticle (10 mg −100 mg range) was utilized to study the effect of molybdenum sulphide (additive) addition on graphene oxide rolled mesoporous manganese oxide nanofiber matrix. Increased quantity of MoS₂ addition increase the electrochemical supercapacitance value of the nanocomposite coated nickel foam based electrode. Nanofibers morphology of mesoporous manganese oxide with reduced graphene oxide is visibly seen in the TEM images. Needle like metallic rich shapes are also obtained due to MoS₂ nanoparticle existence and it inserted in the Nanofiber/graphene sheet structure. The higher supercapacitance values are obtained for Nickel foam modified MoS₂ deposited graphene oxide rolled MnO_x nanocomposite (980 and 788 F/g) under acidic electrolyte medium and charge/discharge cycle stability have also been studied for all prepared nanocomposites.