Edge-Oriented Graphene on Carbon Nanofiber for High-Frequency Supercapacitors

• Published in: Nano-micro letters 2018-01, Vol.10 (1), p.9-8, Article 9
• Main Authors: Islam, Nazifah, Warzywoda, Juliusz, Fan, Zhaoyang
• Format: Article
• Language: English
• Subjects: AC filtering; Aqueous electrolytes; Carbon fibers; Carbon nanofiber; Electric converters; Electric power supplies; Electrodes; Electrolytic capacitors; Electrolytic cells; Engineering; Filtration; Graphene; High-frequency supercapacitor; Kilohertz supercapacitor; Nanofibers; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Nonaqueous electrolytes; Supercapacitors; Vertical graphene
• ISSN: 2311-6706; 2150-5551
• DOI: 10.1007/s40820-017-0162-4

High-frequency supercapacitors are being studied with the aim to replace the bulky electrolytic capacitors for current ripple filtering and other functions used in power systems. Here, 3D edge-oriented graphene (EOG) was grown encircling carbon nanofiber (CNF) framework to form a highly conductive electrode with a large surface area. Such EOG/CNF electrodes were tested in aqueous and organic electrolytes for high-frequency supercapacitor development. For the aqueous and the organic cell, the characteristic frequency at − 45° phase angle was found to be as high as 22 and 8.5 kHz, respectively. At 120 Hz, the electrode capacitance density was 0.37 and 0.16 mF cm −2 for the two cells. In particular, the 3 V high-frequency organic cell was successfully tested as filtering capacitor used in AC/DC converter, suggesting the promising potential of this technology for compact power supply design and other applications.