Preparation and Electrochemical Performance of Composite Electrode Material of Molecular Sieve Coated with Graphene

Abstract

A 3D composite electrode was prepared by ultrasonic dispersion of a suspension mixed proportionally with 4A molecular sieve (4A) and graphene oxide gel (GO). The structure, morphology and electrochemical property of the 4A/reduced graphene oxide (RGO) composite were investigated by X-ray diffraction, Raman spectra, pore analysis, scanning electron microscope (SEM) and electrochemical measurements. The result shows that 4A is firmly adhered on the surface of RGO sheets, which can effectively avoid the stacking of RGO sheets. The RGO sheets link with each other to form a 3D electric conductive network in which can increase the electrical conductivity of the composite. The specific capacitance of 4A/RGO composite can reach 450 F/g at current density of 4 A/g when the mass ratio of graphene oxide and 4A is 1:6. Furthermore, the specific capacitance of 4A/RGO remains at 85.7% after 800 cycles under the same current density. Therefore these results indicate that this new composite possesses good rate capability and cycle stability and its supercapacitive performance is better than that of pure RGO or 4A. The excellent performance of the 4A/RGO composite can be attributed to the synergy between RGO and 4A.