Aqueous supercapacitors based on carbonized silk electrodes. Issue 39 (15th June 2018)

• Record Type: Journal Article
• Authors: Zhang, Limei; Meng, Zhaohui; Qi, Qiaoyun; Yan, Wen; Lin, Naibo; Liu, Xiang Yang
• Is Part Of: RSC advances. Volume 8:Issue 39(2018)
• Page Start: 22146
• Page End: 22153
• Publication Date: 2018-06-15
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c8ra01988f
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : An aqueous symmetrical supercapacitor was achieved by assembling SC-850 electrodes, which possess a specific energy of 14.33 W h kg −1 at a power density of 251 W kg −1 operated over the wide voltage range of 2.0 V in aqueous neutral Na2 SO4 electrolyte. Abstract : Graphitic nitrogen-doped hierarchical porous carbon nanosheets for supercapacitor application were derived from an easily obtained and green silk by simultaneous ZnCl2 activation and FeCl3 graphitization at different heating temperatures. By increasing the heating temperature from 700 to 850 °C, the degree of graphitization and BET surface area rose to their highest levels, while the nitrogen doping content was maintained at 2.24 wt%. Carbonized silk at 850 °C displays a nanosheet morphology and a considerable specific surface area (1285.31 m 2 g −1 ), and it was fabricated into a supercapacitor as an electrode material, exhibiting superior electrochemical performance with a high specific capacitance of 178 F g −1 at 0.5 A g −1 and an excellent rate capability (81% capacitance retention ratio even at 20 A g −1 ) in 1 mol L −1 H2 SO4 electrolyte. A symmetric supercapacitor using carbonized silk at 850 °C as the electrodes has an excellent specific energy of 14.33 W h kg −1 at a power density of 251 W kg −1 operated over a wide voltage range of 2.0 V in aqueous neutral Na2 SO4 electrolyte.