Facile Synthesis of Modified MnO₂/Reduced Graphene Oxide Nanocomposites and their Application in Supercapacitors

Abstract

Herein, KH-550 was used as surface modifier to prepare modified MnO 2 /reduced graphene oxide (M-MnO 2 /rGO) composite electrode materials by utilizing electrostatic interaction at low temperature and normal pressure. X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy were adopted to characterize the material’s phase, morphology, and valence state of elements. The electrochemical properties of the material were measured using a three-electrode system. The results indicate a decrease in the size of the modified MnO 2 particles, and that they were uniformly distributed on the rGO sheets. The M-MnO 2 /rGO composite attained a specific capacitance of 326[Formula: see text]F[Formula: see text]g[Formula: see text] in a solution of 1[Formula: see text]mol[Formula: see text]L[Formula: see text] Na 2 SO 4 at a current density of 0.5[Formula: see text]A[Formula: see text]g[Formula: see text]. The specific capacitance of the material was 92.4% after 1000 cycles. The electrostatic self-assembly method effectively solved the problem of reducing the cycling stability while improving the specific capacitance of the composite materials, and further improved the possibility of applying MnO 2 /rGO in the field of supercapacitors.