采用氨基芘、CTAB、芘羧酸等不同酸碱性的有机小分子使石墨纳米片表面功能化，其中，芘羧酸可以对石墨纳米片表面进行非共价键功能化，增大石墨纳米片间的间距，将其剥离成单层、双层或者多层；使MnO₂在石墨纳米片材料上的负载更加均匀。电化学测试结果显示，经芘羧酸修饰的石墨纳米片/MnO₂复合材料的比电容能达到215 F/g，相较于其他2种（Amin、CTAB）修饰的复合材料比电容能分别高出81%和44%，经4 000次循环后容量几乎无衰减，6 000次后电容保持率仍为81%。

The surface of graphite nanosheets is functionalized by three small organic molecules with different acidity or basicity, including aminopyrene, CTAB and pyrene carboxylic acid (PCA). Among them, PCA can make the surface of graphite nanosheets functionalize with noncovalent bond, which can increase the spacing between the graphite nanosheets and further strip them into monolayer, double or multi layers. Hence the loading of MnO₂ on the graphite nanosheets material is more uniform. The electrochemical test results show that the specific capacitance of the graphite nanosheets/MnO₂ composites modified by PCA can reach 215 F·g^-1, which is 81% and 44% higher than that of the composites modified by aminopyrene and CTAB, respectively. After 4 000 cycles, the capacitance has hardly changed. After 6 000 cycles, the capacitor retention rate is still as high as 81%.