石墨烯纸的制备及电容特性

Preparation and Electrochemical Capacitive Properties of Graphene Paper

利用未经任何分散处理的氧化石墨溶胶在气-液界面自组装得到氧化石墨纸(=10 cm),将氧化石墨纸在不同温度下用水合肼蒸气还原制得石墨烯纸.采用扫描电子显微镜(SEM)、X射线衍射(XRD)、Raman光谱、X射线光电子能谱(XPS)及氮吸附对还原前后样品的微观结构、表面特性、元素组成及比表面积进行了表征,在此基础上考察了还原处理及还原温度对材料电容特性的影响.结果表明,在150℃下还原氧化石墨纸得到的石墨烯纸具有较好的电化学电容特性,其在1000 mA/g恒定充放电电流密度下,6 mol/L KOH电解质溶液中的质量比电容达到142 F/g,1000次充放电循环后电容保持率为99.8%.

Large-scale （φ=10 cm ） graphene paper （ GP ） was prepared by the reduction of graphite oxide paper（ GOP） self-assembled at the liquid/air interface with hydrazine hydrate vapor. The morphology, struc-ture, components and BET surface area of GOP and GP were characterized by scanning electron microscopy （ SEM ） , X-ray diffraction （ XRD ） , Raman spectroscopy, X-ray photoelectron spectroscopy （ XPS ） and nitrogen adsorption-desorption analysis. Furthermore, influence of reduction and reduction temperature on the super-capacitive properties was investigated. It is found that the graphene paper fabricated at 150 ℃ exhibits high capacitive behavior and long charge/discharge cycle life at a current density of 1000 mA/g. The discharge capacitance of the material in an aqueous electrolyte of 6 mol/L KOH is 142 F/g and the capaci-tance retention is 99. 8% after 1000 charge/discharge cycles.