Opening the internal structure for transport of ions: improvement of the structural and chemical properties of single-walled carbon nanohorns for supercapacitor electrodes

Wojciech Zieba; Piotr Olejnik; Stanislaw Koter; Piotr Kowalczyk; Marta E Plonska-Brzezinska; Artur P Terzyk

doi:10.1039/d0ra07748h

Opening the internal structure for transport of ions: improvement of the structural and chemical properties of single-walled carbon nanohorns for supercapacitor electrodes

RSC Adv. 2020 Oct 19;10(63):38357-38368. doi: 10.1039/d0ra07748h. eCollection 2020 Oct 15.

Authors

Wojciech Zieba¹, Piotr Olejnik², Stanislaw Koter³, Piotr Kowalczyk⁴, Marta E Plonska-Brzezinska², Artur P Terzyk¹

Affiliations

¹ Faculty of Chemistry, Physicochemistry of Carbon Materials Research Group, Nicolaus Copernicus University in Toruń Gagarin Street 7 87-100 Toruń Poland aterzyk@chem.uni.torun.pl.
² Department of Organic Chemistry, Faculty of Pharmacy with the Division of Laboratory Medicine, Medical University of Bialystok Mickiewicza 2A 15-222 Bialystok Poland marta.plonska-brzezinska@umb.edu.pl.
³ Faculty of Chemistry, Department of Physical Chemistry, Nicolaus Copernicus University in Toruń Gagarin Street 7 87-100 Toruń Poland.
⁴ College of Science, Health, Engineering and Education, Murdoch University WA, 6150 Australia.

Abstract

We investigated the electrochemical performance of single-walled carbon nanohorns (SWCNHs) for use as supercapacitor electrodes. For the first time, we used acid-treatment for oxidation of SWCNHs and hole creation in their structure. A detailed study was performed on the correlation between the oxidation of SWCNHs via acid treatment and variable acid treatment times, the structural properties of the oxidized carbon nanostructures, and the specific capacitance of the SWCNH electrodes. We showed that simple functionalization of carbon nanostructures under controlled conditions leads to an almost 3-fold increase in their specific capacitance (from 65 to 180 F g^-1 in 0.1 M H₂SO₄). This phenomenon indicates higher accessibility of the surface area of the electrodes by electrolyte ions as a result of gradual opening of the SWCNH internal channels.