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

ABSTRACT: 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.

SUBMITTER: Islam N

PROVIDER: S-EPMC6199059 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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

Islam Nazifah N Warzywoda Juliusz J Fan Zhaoyang Z

Nano-micro letters 20171026 1

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 cha ...[more]

PMID: 30393658

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