| 초록 |
Graphene is considered a promising active material for electric double layer supercapacitors (EDLCs) due to its high electric conductivity and lightweight nature. However, for practical uses as a power source of electronic devices, porous structure is preferred to maximize gravimetric energy density . Here, we introduce a novel synthetic approach of mesoporous graphene (m-G), in which self-assembled mesoporous structures of poly(styrene)-b-poly(2-vinylpyridine) copolymer (PS-b-P2VP) are exploited as a catalytic template and a carbon source. The sequential heat treatment of carbonization and catalytic pyrolysis produces m-G without collapsing the preformed mesoporous structures, leading to well-defined graphene with mesopore (~4.0 nm) and high specific surface area (409 m2/g). As a result, m-G based EDLCs showed stable electrochemical behaviors in a wide range of operation voltage (0 ~ 4 V), a high specific capacitance (63 F/g at 0.2 A/g), a high- energy density of 35 Wh/kg at power density of 409 W/kg, and excellent cycle stability. These results showed that mesoporous graphene has high potential for high-performance energy storage devices. |
