title: Excellent capacitive performance of a three-dimensional hierarchical porous graphene/carbon composite with a superhigh surface area.
abstract: Three-dimensional hierarchical porous graphene/carbon composite was successfully synthesized from a solution of graphene oxide and a phenolic resin by using a facile and efficient method. The morphology, structure, and surface property of the composite were investigated intensively by a variety of means such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption, Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR). It is found that graphene serves as a scaffold to form a hierarchical pore texture in the composite, resulting in its superhigh surface area of 2034 m(2) g(-1), thin macropore wall, and high conductivity (152 S m(-1)). As evidenced by electrochemical measurements in both EMImBF4 ionic liquid and KOH electrolyte, the composite exhibits ideal capacitive behavior, high capacitance, and excellent rate performance due to its unique structure. In EMImBF4 , the composite has a high energy density of up to 50.1 Wh kg(-1) and also possesses quite stable cycling stability at 100 °C, suggesting its promising application in high-temperature supercapacitors. In KOH electrolyte, the specific capacitance of this composite can reach up to an unprecedented value of 186.5 F g(-1), even at a very high current density of 50 A g(-1), suggesting its prosperous application in high-power applications.
authors.affiliation: School of Science, State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580 (P.R. China), Fax: (+86) 533-86983579.
authors.forename: Xue Jin
authors.initials: XJ
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Xing
authors.forename: Jin
authors.initials: J
authors.lastname: Zhou
authors.forename: Gui Qiang
authors.initials: GQ
authors.lastname: Wang
authors.forename: Shu Ping
authors.initials: SP
authors.lastname: Zhuo
authors.forename: Zi Feng
authors.initials: ZF
authors.lastname: Yan
authors.forename: Qing Zhong
authors.initials: QZ
authors.lastname: Xue
authors.forename: Shi Zhang
authors.initials: SZ
authors.lastname: Qiao
keywords: carbon; conducting materials; graphene; supercapacitors; surface chemistry