title: Hierarchical micro- and mesoporous carbide-derived carbon as a high-performance electrode material in supercapacitors.
abstract: Ordered mesoporous carbide-derived carbon (OM-CDC) materials produced by nanocasting of ordered mesoporous silica templates are characterized by a bimodal pore size distribution with a high ratio of micropores. The micropores result in outstanding adsorption capacities and the well-defined mesopores facilitate enhanced kinetics in adsorption processes. Here, for the first time, a systematic study is presented, in which the effects of synthesis temperature on the electrochemical performance of these materials in supercapacitors based on a 1 M aqueous solution of sulfuric acid and 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid are reported. Cyclic voltammetry shows the specific capacitance of the OM-CDC materials exceeds 200 F g(-1) in the aqueous electrolyte and 185 F g(-1) in the ionic liquid, when measured in a symmetric configuration in voltage ranges of up to 0.6 and 2 V, respectively. The ordered mesoporous channels in the produced OM-CDC materials serve as ion-highways and allow for very fast ionic transport into the bulk of the OM-CDC particles. At room temperature the enhanced ion transport leads to 75% and 90% of the capacitance retention at current densities in excess of ∼10 A g(-1) in ionic liquid and aqueous electrolytes, respectively. The supercapacitors based on 250-300 μm OM-CDC electrodes demonstrate an operating frequency of up to 7 Hz in aqueous electrolyte. The combination of high specific capacitance and outstanding rate capabilities of the OM-CDC materials is unmatched by state-of-the art activated carbons and strictly microporous CDC materials.
authors: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors: Marcus
authors: M
authors: Rose
authors: Yair
authors: Y
authors: Korenblit
authors: Emanuel
authors: E
authors: Kockrick
authors: Lars
authors: L
authors: Borchardt
authors: Martin
authors: M
authors: Oschatz
authors: Stefan
authors: S
authors: Kaskel
authors: Gleb
authors: G
authors: Yushin
mesh_terms: D002244:Carbon / Q000737:chemistry*; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D004573:Electrolytes; D016062:Porosity; D013059:Spectrum Analysis, Raman; D013464:Sulfuric Acids / Q000737:chemistry; D013696:Temperature
chemical_list: D004573:Electrolytes; D013464:Sulfuric Acids; D002244:Carbon; C033158:sulfuric acid