A simple method is demonstrated to prepare spongy adenine-functionalized graphene (SFG) as interconnected, porous 3-dimensional (3D) network crinkly sheets. Such 3D network structure provides better contact at the electrode/electrolyte interface and facilitates the charge transfer kinetics. The fabricated SFG was characterized by X-ray diffraction (XRD), FTIR, scanning electron microscopy (FESEM), Raman spectroscopy, thermogravimetric analysis (TGA), UV−vis absorption spectroscopy, and transmission electron microscopy (TEM). The synthesized materials have been evaluated as supercapacitor materials in 0.5 M H2SO4 using cyclic voltammetry (CV) at different potential scan rates, and galvanostatic charge/discharge tests at different current densities. The SFG electrodes showed a maximum specific capacitance of 333 F/g at scan rate of 1 mV/s and exhibited excellent cycling retention of 102% after 1000 cycles at 200 mV/s. The energy density was 64.42 Wh/kg with a power density of 599.8 W/kg at 1.0 A/g. Those figures of merit are much higher than those reported for graphene-based materials tested under similar conditions. The observed high performance can be related to the synergistic effects of the spongy structure and the adenine functionalization.
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机译：演示了一种简单的方法将海绵状腺嘌呤功能化石墨烯（SFG）制备为相互连接的多孔3维（3D）网络皱褶片。这种3D网络结构在电极/电解质界面处提供了更好的接触，并促进了电荷转移动力学。通过X射线衍射（XRD），FTIR，扫描电子显微镜（FESEM），拉曼光谱，热重分析（TGA），紫外可见吸收光谱和透射电子显微镜（TEM）对制成的SFG进行了表征。使用循环伏安法（CV）在不同的电位扫描速率下以及在不同的电流密度下进行恒电流充电/放电测试，已将合成的材料评估为0.5 M H2SO4中的超级电容器材料。 SFG电极在1 mV / s的扫描速率下显示最大比电容为333 F / g，并在200 mV / s的1000次循环后表现出102％的出色循环保持率。能量密度为64.42 Wh / kg，功率密度为1.0 A / g时为599.8 W / kg。这些性能指标远高于在类似条件下测试的基于石墨烯的材料的性能指标。观察到的高性能可能与海绵状结构和腺嘌呤功能化的协同效应有关。
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