title: Studies on supercapacitor electrode material from activated lignin-derived mesoporous carbon.
abstract: We synthesized mesoporous carbon from pre-cross-linked lignin gel impregnated with a surfactant as the pore-forming agent and then activated the carbon through physical and chemical methods to obtain activated mesoporous carbon. The activated mesoporous carbons exhibited 1.5- to 6-fold increases in porosity with a maximum Brunauer-Emmett-Teller (BET) specific surface area of 1148 m(2)/g and a pore volume of 1.0 cm(3)/g. Both physical and chemical activation enhanced the mesoporosity along with significant microporosity. Plots of cyclic voltammetric data with the capacitor electrode made from these carbons showed an almost rectangular curve depicting the behavior of ideal double-layer capacitance. Although the pristine mesoporous carbon exhibited a range of surface-area-based capacitance similar to that of other known carbon-based supercapacitors, activation decreased the surface-area-based specific capacitance and enhanced the gravimetric specific capacitance of the mesoporous carbons. A vertical tail in the lower-frequency domain of the Nyquist plot provided additional evidence of good supercapacitor behavior for the activated mesoporous carbons. We have modeled the equivalent circuit of the Nyquist plot with the help of two constant phase elements (CPE). Our work demonstrated that biomass-derived mesoporous carbon materials continue to show potential for use in specific electrochemical applications.
authors.affiliation: Materials Science and Technology Division, ‡Chemical Sciences Division, and §Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37931-6053, United States.
authors.forename: Dipendu
authors.initials: D
authors.lastname: Saha
authors.forename: Yunchao
authors.initials: Y
authors.lastname: Li
authors.forename: Zhonghe
authors.initials: Z
authors.lastname: Bi
authors.forename: Jihua
authors.initials: J
authors.lastname: Chen
authors.forename: Jong K
authors.initials: JK
authors.lastname: Keum
authors.forename: Dale K
authors.initials: DK
authors.lastname: Hensley
authors.forename: Hippolyte A
authors.initials: HA
authors.lastname: Grappe
authors.forename: Harry M
authors.initials: HM
authors.lastname: Meyer
authors.forename: Sheng
authors.initials: S
authors.lastname: Dai
authors.forename: M Parans
authors.initials: MP
authors.lastname: Paranthaman
authors.forename: A K
authors.initials: AK
authors.lastname: Naskar