Single-Walled Carbon Nanotubes Wrapped by Cationic Nitrogen-Doped Carbon for Electrocatalytic Applications
Sangwoo Chae, Phu Quoc Phan, Gasidit Panomsuwan, Maria Antoaneta Bratescu, Takeshi Hashimoto, Katsuya Teshima, Nagahiro Saito
Abstract
The exploration of novel carbon material systems has emerged as a promising strategy for yielding unique and unconventional functional properties. In this study, a cationic nitrogen-doped carbon-wrapped single-walled carbon nanotube (CN–C@SWCNT) was synthesized for the first time via solution plasma (SP) by using an aniline aqueous solution with the SWCNT dispersion under ambient conditions. The reactive species produced from SP led to the formation of cationic nitrogen-doped carbon (CN–C) completely wrapped around SWCNT. Raman spectroscopy, electron diffraction, and X-ray photoelectron spectroscopy confirmed the presence of cationic nitrogen. CN–C@SWCNT exhibited an excellent electrical conductivity of 120.30 S cm–1. Room-temperature hall-effect measurements revealed p-type semiconducting behavior for CN–C@SWCNT, with a carrier concentration of 4.6 × 1020 cm–3. The electrical conductivity and carrier concentration of p-type CN–C@SWCNT were greater than those reported previously for carbon-based materials. The high electrical properties of CN–C@SWCNT were synergistically related to a conducting bridge between CN–C and SWCNT conducting domains and the presence of doped cationic nitrogen. The SP-synthesized CN–C@SWCNT demonstrates immense potential as an emerging class of p-type carbon materials in advanced electrocatalytic applications.