中文摘要：

将石墨烯电极与离子液体N-甲基-N-丙基吡咯烷氰酸盐（[C3mpyr][OCN]）/碳酸丙烯酯（PC）混合电解液组装成超级电容器,采用循环伏安（CV）、交流阻抗（EIS）、恒电流充放电（GCD）等方法研究了其在50、60、70℃环境下的电化学性能。结果表明：该体系在较高温度下的电化学性能优异,70℃下其比容量最高可达295 F·g（-1）,能量密度可达118 W·h·kg（-1）,且恒电流充放电循环稳定性较好。

英文摘要：

Supercapacitors were constructed with graphene as electrodes and ionic liquid N-methyl-Npropylpyrrolidinium cyanate（[C3mpyr] [OCN]）/propylene carbonate（PC） as the mixed electrolytes. The electrochemical properties of constructed supercapacitors were tested at 50, 60 and 70℃ by cyclic voltammetry（CV）, electrochemical impedance spectroscopy（EIS） and galvanostatic charge/discharge（GCD）. The results indicated that the constructed supercapacitors exhibited good electrochemical properties at high operating temperatures. The supercapacitors gave the specific capacity of 295 F·g（-1） and delivered an energy density as high as 118 W·h·kg（-1） at 70℃ with the current density of 0.5 A·g（-1）. Additionally, the constructed supercapacitors showed a good cycling stability.