High capacitance of coarse-grained carbide derived carbon electrodes

作者：Dyatkin Boris; Gogotsi Oleksiy; Malinovskiy Bohdan; Zozulya Yuliya; Simon Patrice; Gogotsi Yury

来源：Journal of Power Sources, 2016, 306: 32-41.

DOI：10.1016/j.jpowsour.2015.11.099

• Supercapacitor
• Carbide-derived carbon
• Electrode material
• Energy density
• Grid storage
• Porous carbon

We report exceptional electrochemical properties of supercapacitor electrodes composed of large, granular carbide-derived carbon (CDC) particles. Using a titanium carbide (TiC) precursor, we synthesized 70-250 mu m sized particles with high surface area and a narrow pore size distribution. Electrochemical cycling of these coarse-grained powders defied conventional wisdom that a small particle size is strictly required for supercapacitor electrodes and allowed high charge storage densities, rapid transport, and good rate handling ability. The material showcased capacitance above 100 F g(-1), at sweep rates as high as 250 mV s(-1) in organic electrolyte. 250-1000 micron thick dense CDC films with up to 80 mg cm(-2) loading showed superior areal capacitances. The material significantly outperformed its activated carbon counterpart in organic electrolytes and ionic liquids. Furthermore, large internal/external surface ratio of coarse-grained carbons allowed the resulting electrodes to maintain high electrochemical stability up to 3.1 V in ionic liquid electrolyte. In addition to presenting novel insights into the electrosorption process, these coarse-grained carbons offer a pathway to low-cost, high-performance implementation of supercapacitors in automotive and grid-storage applications.

• 出版日期2016-2-29