Huge enhancement of energy storage capacity and power density of supercapacitors based on the carbon dioxide activated microporous SiC-CDC. (10th April 2015)

• Record Type: Journal Article
• Authors: Tee, Ester; Tallo, Indrek; Kurig, Heisi; Thomberg, Thomas; Jänes, Alar; Lust, Enn
• Is Part Of: Electrochimica acta. Volume 161(2015)
• Page Start: 364
• Page End: 370
• Publication Date: 2015-04-10
• Subjects: Supercapacitor -- Carbide derived carbon -- SiC-CDC -- Carbon dioxide activation -- High power density; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2015.02.106
• Languages: English
• ISSNs: 0013-4686

Abstract

Graphical abstract: Abstract: Nanostructured carbide-derived carbons (CDC) were synthesized from SiC powders (SiC-CDC) via gas phase chlorination within the temperature range from 1000 °C to 1100 °C. Thereafter the CDCs were additionally activated by CO2 treatment method, resulting in nearly two-fold increase in specific surface area. The results of X-ray diffraction, high-resolution transmission electron microscopy and Raman spectroscopy showed that the synthesized CDC materials are mainly amorphous, however containing small graphitic crystallites. The low-temperature N2 sorption experiments were performed and the specific micropore surface areas from 1100 m 2 g −1 up to 2270 m 2 g −1 were obtained, depending on the extent of CO2 activation. The energy and power density characteristics of the supercapacitors based on 1 M (C2 H5 )3 CH3 NBF4 solution in acetonitrile and SiC-CDC as an electrode material were investigated using the cyclic voltammetry, electrochemical impedance spectroscopy, galvanostatic charge/discharge and constant power discharge methods. The electrochemical data indicated two-times increase in specific capacitance. Most importantly, the activation of SiC-CDC with CO2 significantly increases the performance (energy density, power density, etc.) of the supercapacitors especially at higher potential scan rates and at higher power loads.