Li Jing, Xie Huaqing, Li Yang, Wang Jifen
School of Urban Development and Environmental Engineering, Shanghai Second Polytechnic University, Shanghai 201209, China.
J Nanosci Nanotechnol. 2013 Feb;13(2):1132-5. doi: 10.1166/jnn.2013.6004.
Composite films of graphene and polyaniline nanofibers are prepared by in situ polymerization of aniline monomer in graphene suspension. The morphology and microstructure of samples are examined by scanning electron microscopy (SEM), transition electron microscopy (TEM), and X-ray diffraction (XRD). Electrochemical performances are characterized by cyclic voltammetry (CV) and galvanostatic charge/discharge measurements. Graphene is homogeneously coated by polyaniline nanofibers with diameter of 40 nm. Supercapacitors based on the graphene/polyaniline conductive composite films exhibit large electrochemical capacitance (994 F/g) at a discharge rate of 2.0 A/g in 1 M H2SO4 solution, which is much higher than the graphene (320 F/g) and polyaniline electrode (210 F/g). The excellent performance is not only due to the graphene which can provide more active sites for nucleation of polyaniline, but also associated with a good redox activity of ordered polyaniline nanofibers. Moreover, the composite films exhibit excellent long cycle life during charge/discharge processes. After 1000 cycles, the specific capacitance decreases 11% of initial capacitance compared to 28% for polyaniline nanofibers. The resulting composite is a promising electrode material for high-performance electrical energy storage devices.
通过在石墨烯悬浮液中原位聚合苯胺单体来制备石墨烯和聚苯胺纳米纤维的复合薄膜。通过扫描电子显微镜（SEM）、透射电子显微镜（TEM）和X射线衍射（XRD）对样品的形态和微观结构进行了研究。通过循环伏安法（CV）和恒电流充/放电测量对电化学性能进行了表征。石墨烯被直径为40nm的聚苯胺纳米纤维均匀包覆。基于石墨烯/聚苯胺导电复合薄膜的超级电容器在1M硫酸溶液中以2.0A/g的放电速率表现出较大的电化学电容（994F/g），这远高于石墨烯（320F/g）和聚苯胺电极（210F/g）。优异的性能不仅归因于能够为聚苯胺成核提供更多活性位点的石墨烯，还与有序聚苯胺纳米纤维良好的氧化还原活性有关。此外，复合薄膜在充/放电过程中表现出优异的长循环寿命。经过1000次循环后，与聚苯胺纳米纤维的28%相比，比电容降低了初始电容的11%。所得复合材料是一种用于高性能电能存储装置的有前景的电极材料。
