Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, Hunan University, Changsha, 410082, PR China.
Nanoscale. 2012 Dec 21;4(24):7810-6. doi: 10.1039/c2nr31902k. Epub 2012 Nov 12.
Electrochemical supercapacitors have drawn much attention because of their high power and reasonably high energy densities. However, their performances still do not reach the demand of energy storage. In this paper β-cobalt sulfide nanoparticles were homogeneously distributed on a highly conductive graphene (CS-G) nanocomposite, which was confirmed by transmission electron microscopy analysis, and exhibit excellent electrochemical performances including extremely high values of specific capacitance (~1535 F g(-1)) at a current density of 2 A g(-1), high-power density (11.98 kW kg(-1)) at a discharge current density of 40 A g(-1) and excellent cyclic stability. The excellent electrochemical performances could be attributed to the graphene nanosheets (GNSs) which could maintain the mechanical integrity. Also the CS-G nanocomposite electrodes have high electrical conductivity. These results indicate that high electronic conductivity of graphene nanocomposite materials is crucial to achieving high power and energy density for supercapacitors.
电化学超级电容器因其高功率和合理的高能量密度而受到广泛关注。然而，它们的性能仍未达到储能的要求。在本文中，β-硫化钴纳米粒子均匀分布在高导电性的石墨烯（CS-G）纳米复合材料上，这通过透射电子显微镜分析得到了证实，并且表现出优异的电化学性能，包括在 2 A g(-1) 的电流密度下极高的比电容值（~1535 F g(-1))，在 40 A g(-1) 的放电电流密度下具有高的功率密度（11.98 kW kg(-1))和优异的循环稳定性。优异的电化学性能可归因于石墨烯纳米片（GNSs），其可保持机械完整性。此外，CS-G 纳米复合材料电极具有高导电性。这些结果表明，对于超级电容器而言，高导电性的石墨烯纳米复合材料对于实现高功率和能量密度至关重要。
