Graphene oxide induced high dielectricity in CS/PMMA solid polymer electrolytes and the enhanced specific capacitance with Ag decorated MnCoFeO4 nanoparticles anchored graphene sheets in hybrid solid-state supercapacitors

Abstract

Enhanced specific capacitance with silver decorated manganese cobalt ferrite (MnCoFeO4) nanoparticles anchored onto graphene sheets as an electrode and graphene oxide (GO) grafted chitosan (CS)/ polymethyl methacrylate (PMMA) as solid electrolytes in hybrid solid-state supercapacitors has been reported here. GO doped CS/PMMA blended solid electrolytes exhibit high ionic conductivity (∼4.5 × 10−3 S/cm) and dielectric constant (∼4018) at room temperature. Thermal analysis suggests a significant reduction in crystallinity in GO grafted CS/PMMA electrolytes. The scaling of the ac conductivity and dielectric constant suggests that the relaxation phenomenon is independent of the CS/PMMA blending compositions but dependent on the GO doping. The interaction between Li+cation and the amide functional group is weakened remarkably on grafting the electrolytes with GO. An effective specific capacitance of ∼294 Fg−1 is obtained with Ag decorated MnCoFeO4 nanoparticles anchored onto rGO electrode which is ∼2.5 times enhanced compared to that with MnCoFeO4 electrode.