Abstract The tri-doped (chromium, fluorine and nitrogen) graphene sheets (CFNG) have been prepared using quinolinium fluorochromate (QFC) as the single and novel source. Graphene oxide (GO) and CFNG were synthesized by modified Hummers method and simple hydrothermal method, respectively, and their electrochemical properties towards supercapacitor were studied. The HR-TEM images provide the crumpled sheet like morphology of CFNG. XPS reveals the presence of Cr, F and N in CFNG. The electrochemical studies such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge (GCD) were carried out using 1 M H2SO4 to evaluate the capacitive behaviour in three-electrode cells. A better storage capacitive behaviour of about 363 F/g at a current density of 0.5 A/g was achieved by CFNG. The capacitive performance of CFNG was also tested in two electrode cells, in which, a symmetric device was fabricated with CFNG, which exhibited specific capacitance of 160 F/g for 0.5 A/g. The symmetric CFNG supercapacitor device further delivers respective energy density and power density of 14.23 Wh/kg and 300 W/Kg with excellent capacitance retention of 98.8% and coulombic efficiency of 98.3% for over 1000 charge-discharge cycles. The electrochemical results were indicating that CFNG would be a potential candidate as an active electrode material for supercapacitors.

中文翻译：

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铬、氟和氮三掺杂石墨烯片作为对称超级电容器的活性电极材料

摘要 以氟铬酸喹啉 (QFC) 为单一来源，制备了三掺杂（铬、氟和氮）石墨烯片（CFNG）。分别采用改进的 Hummers 法和简单水热法合成了氧化石墨烯 (GO) 和 CFNG，并研究了它们对超级电容器的电化学性能。HR-TEM 图像提供了 CFNG 的皱折片状形态。XPS 揭示了 CFNG 中存在 Cr、F 和 N。使用 1 M H2SO4 进行循环伏安法 (CV)、电化学阻抗谱 (EIS) 和恒电流充放电 (GCD) 等电化学研究，以评估三电极电池的电容行为。CFNG 在 0.5 A/g 的电流密度下实现了约 363 F/g 的更好的存储电容行为。CFNG 的电容性能也在两个电极电池中进行了测试，其中，用 CFNG 制造了一个对称器件，其在 0.5 A/g 下表现出 160 F/g 的比电容。对称 CFNG 超级电容器装置进一步提供 14.23 Wh/kg 和 300 W/Kg 的能量密度和功率密度，在超过 1000 次充放电循环中具有 98.8% 的优异电容保持率和 98.3% 的库仑效率。电化学结果表明，CFNG 将成为超级电容器活性电极材料的潜在候选材料。23 Wh/kg 和 300 W/Kg，在超过 1000 次充放电循环中具有 98.8% 的出色电容保持率和 98.3% 的库仑效率。电化学结果表明，CFNG 将成为超级电容器活性电极材料的潜在候选材料。23 Wh/kg 和 300 W/Kg，在超过 1000 次充放电循环中具有 98.8% 的出色电容保持率和 98.3% 的库仑效率。电化学结果表明，CFNG 将成为超级电容器活性电极材料的潜在候选材料。