Surfactant-free synthesis of a nanoperforated graphene/nitrogen-doped carbon nanotube composite for supercapacitors

Yeon Jun Choi, Hyun Kyung Kim, Suk Woo Lee, Young Hwan Kim, Hee Chang Youn, Kwang Chul Roh, Kwang Bum Kim

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

A nanoperforated graphene/carbon nanotube (PG/CNT) composite is fabricated by electrostatic interaction of graphene oxide (GO) and nitrogen-doped CNTs, and subsequent catalytic carbon gasification. The nitrogen-doped sites (pyridinic N sites) of the CNTs are protonated under acidic conditions owing to the lone pair electrons, rendering the CNTs positively charged. The nitrogen-doped CNTs are uniformly incorporated into PG to form the PG/CNT composite through electrostatic attraction between the positively charged CNTs and the negatively charged GO. The resulting PG/nitrogen-doped CNT (N-CNT) composite exhibits outstanding electrochemical properties, showing high specific capacitance (288 F g-1 at 0.5 A g-1) and high rate capability (267 F g-1 at 20 A g-1) as well as excellent cycling stability (99% capacitance retention after 30 000 charge/discharge cycles). This is attributable to not only the formation of a high concentration of edge sites in PG and improvements of cross-plane ion diffusion owing to the nanoperforations, but also the enhancements in the ion-accessible area and in-plane ion diffusion due to the incorporation of N-CNT nanospacers into PG.

Original languageEnglish
Pages (from-to)22607-22617
Number of pages11
JournalJournal of Materials Chemistry A
Volume5
Issue number43
DOIs
Publication statusPublished - 2017 Jan 1

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)

Cite this