所属单位：化学工程学院

教研室：化工原理

发表刊物：RSC Advances

项目来源：其他课题

摘要：Graphenematerial prepared by reducing graphene oxide (GO, prepared by themodified Hummersmethod) has been considered as one of the most promising candidates for electrode materials for supercapacitors due to its mass producibility, high electrical conductivity, large specific surface area, and superior mechanical strength. However, it usually exhibits an unfavorable cycling performance, mainly large capacitance fading in the initial thousands of cycles, as shown but not discussed in some previous reports. In this paper, we not only find a similar phenomenon to a commercial graphene material, but also develop a very simple method to successfully enhance its electrochemical properties in terms of cycle life as well as high-rate performance, leakage current and alternating current impedance. For example, the relatively low capacitance retention of about 89.9% at the initial 1000th cycle was increased up to 99.7% after improvement, the capacitance retention was raised to 73% from 43% at a scan rate of 100 mV s-1 in cyclic voltammetry, and leakage current density was significantly more than halved (from 2.42 mA g-1 to 1.01 mA g-1). Additionally, the reasons for the improvement are also disclosed by analyzing the characterization results of X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and Raman spectroscopy. It is found that the optimization of the functional groups of doped nitrogen and oxygen atoms may contribute to the improvement of cycle life and decrease of leakage current density, and the enhanced rate performance can be attributed to the increase of electrical conductivity.

第一作者：李伟

论文类型：期刊论文

卷号：5

期号：17

页面范围：1

字数：4

是否译文：否

发表时间：2015-01-05