Facile and fast microwave-assisted formation of reduced graphene oxide-wrapped manganese cobaltite ternary hybrids as improved supercapacitor electrode material

Abstract

Microwave-assisted, facile, fast and one pot method is reported for synthesis of ternary hybrids material containing manganese cobaltite (MnCo2O4) nanoparticles (MCO NPs) wrapped by microwave exfoliated-reduced graphene oxide nanosheets (ME-rGO NSs) for improved supercapacitor electrode materials. In synthesized ME-rGO NSs wrapped MCO NPs (GW-MCO) ternary hybrids material, MCO NPs are completely wrapped by ME-rGO NSs and provides a conductive scaffold constructed from wrinkled ME-rGO NSs. Owning to this unique GW-MCO ternary hybrids formation, the used ME-rGO NSs possesses high surface area (391.76 m2/g) with suitable pore size distribution, which can effectively accommodate the electrolyte ions migration inside hybrids. The interconnected GW-MCO ternary hybrids conducting network, as an adhesive, can maintain structural stability and promote charge transport by encapsulating agglomerated nanosized MCO NPs. The structural and morphological studies of synthesized GW-MCO ternary hybrids was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), Raman spectra, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area. Moreover, the GW-MCO ternary hybrids based electrode for supercapacitor delivers a high specific capacitance of 562 F/g (20 mV/s) and excellent long-term cycle stability (remain 92.3% after 2000 cycles). This study provides a new, simple and fast approach to wrap different kind of metal oxide NPs by ME-rGO NSs to fabricate electrode material for high performance supercapacitor.