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Title: Band gap opening of metallic single-walled carbon nanotubes via noncovalent symmetry breaking
Covalent bonding interactions determine the energy–momentum (E–k) dispersion (band structure) of solid-state materials. Here, we show that noncovalent interactions can modulate theE–kdispersion near the Fermi level of a low-dimensional nanoscale conductor. We demonstrate that low energy band gaps may be opened in metallic carbon nanotubes through polymer wrapping of the nanotube surface at fixed helical periodicity. Electronic spectral, chiro-optic, potentiometric, electronic device, and work function data corroborate that the magnitude of band gap opening depends on the nature of the polymer electronic structure. Polymer dewrapping reverses the conducting-to-semiconducting phase transition, restoring the native metallic carbon nanotube electronic structure. These results address a long-standing challenge to develop carbon nanotube electronic structures that are not realized through disruption of π conjugation, and establish a roadmap for designing and tuning specialized semiconductors that feature band gaps on the order of a few hundred meV.  more » « less
Award ID(s):
2140249
PAR ID:
10531709
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Proceedings of the National Academy
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
121
Issue:
12
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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