2015年

High performance graphene composite microsphere electrodes for capacitive deionisation

发文时间:2018-11-06

Graphene oxide/resorcinol-formaldehyde microsphere (GORFM) was synthesised by a simple-inverse suspension polymerisation under ambient pressure drying and the graphene composite microsphere (GCM) was obtained by carbonisation in a nitrogen atmosphere. The morphologies and microstructures of GORFM and GCM samples were characterised by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and surface area ****ysis. The results showed that the diameters of GORFM were controlled in the range of 5-10 mu M with perfect sphericity. The inner layer of GORFM was composed of resorcinol-formaldehyde (RF) particles, and the outer layer was the wrinkled GO sheets intercalated with RF through chemical and physical interactions. The GCM-1.5 sample achieved the highest specific surface area of 1128 m(2)/g and the mesopore area was 699 m(2)/g. The electrochemical behaviours of GCM as an electrode were investigated by cyclic voltammograms, electrochemical impedance spectroscopy and capacitivedeionisation (CDI). The specific capacitance and electrosorption capacity of GCM-1.5 was 290.2 F/g and 33.52 mg/g, respectively. The current efficiencies were in the range of 77.75-81.41%. These results implied that GCM had a potential application in CDI due to its low-cost and high performance. (C) 2015 Elsevier Ltd. All rights reserved.