Carrier Doping into Single-Walled Carbon Nanotubes through Encapsulation of Fluorinated Fullerenes

This is the authors' abstract. We don't add key points for this paper.

The fluorinated fullerene C 60 F x ( x ≈ 42) was synthesized by heating C 60 fullerene in a fluorine gas atmosphere. Subsequently, the encapsulation of C 60 F x within single-walled carbon nanotubes (SWCNTs) was achieved by placing C 60 F x and SWCNTs inside a glass tube and subjecting them to further heat treatment under vacuum conditions. The formation of SWCNTs encapsulating C 60 F x (C 60 F x @SWCNT) was confirmed through various techniques, including transmission electron microscopy, X-ray diffraction experiments, Raman scattering experiments, and X-ray photoelectron spectroscopy. Furthermore, measurements of the electrical conductivity and the Seebeck coefficient of the C 60 F x @SWCNT revealed that SWCNTs were hole-doped as a result of the encapsulation of C 60 F x . Similar measurement was conducted for SWCNTs containing tetracyanoquinodimethane (TCNQ), and it was observed that C 60 F x had the larger hole-doping effect per molecule than TCNQ. Additionally, it was demonstrated that C 60 F x @SWCNT functions effectively as oxygen reduction electrodes.