Facile synthesis of reduced graphene oxide/NiMn2O4 nanorods hybrid materials for high-performance supercapacitors

Abstract

We report a mild strategy to synthesize reduced graphene oxide/spinel nickel manganese oxide (rGO/NiMn2O4) nanorods composites. The rGO/NiMn2(C2O4)3 precursors were prepared via coprecipitation method in ethanol-water system and the composites were obtained by calcining the precursors in air. The hybrid materials have been characterized by X-ray powder diffraction, Raman spectra, X-Ray photoelectron spectroscopy, high-resolution transmission electron microscopy and field emission scanning electron microscopy. Different electrochemical measurements have been used in a three electrode system to study the electrochemical performance such as cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy. The typical hybrid materials (30wt% rGO) display a high specific capacitance (693.00Fg−1 at 1Ag−1) and prominent cycling stability (91.38% capacitance retention after 2000 cycles at 5Ag−1), indicating that the composites possess potential application as excellent electrode material.