Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6613181 | Electrochimica Acta | 2014 | 48 Pages |
Abstract
Electrode properties of defect-introduced graphene sheets (GSs) in an acid aqueous electrolyte as an electrode material for electrochemical capacitors were investigated. Defects were successfully introduced into graphene structures through repeated oxidation of graphite followed by rapid thermal exfoliation. The specific surface area was increased up to 991 m2Â gâ1 by the defect introduction process. A GS electrode with a high amount of defects maintained a stable specific capacitance of 136 F gâ1 at a current density of 500 mA gâ1 for 1000 cycles, which is larger than that of GSs with a low amount of defects. A large specific capacitance of 115 F gâ1 was also exhibited at a high current density of 5000Â mAÂ gâ1. These capacitances were almost maintained even after the specific surface area was reduced by the sheet-restacking process, indicating that the large capacitance is derived from the defects introduced in the graphene structure.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Chemical Engineering (General)
Authors
Wonkyun Lee, Shinya Suzuki, Masaru Miyayama,