Enhanced Tunneling in a Hybrid of Single-Walled Carbon Nanotubes and Graphene

Author(s)
Yongping Liao, Kimmo Mustonen, Semir Tulić, Viera Skákalová, Sabbir A. Khan, Patrik Laiho, Qiang Zhang, Changfeng Li, Mohammad R.A. Monazam, Jani Kotakoski, Harri Lipsanen, Esko I. Kauppinen
Abstract

Transparent and conductive films (TCFs) are of great technological importance. Their high transmittance, electrical conductivity, and mechanical strength make single-walled carbon nanotubes (SWCNTs) a good candidate for the raw material for TCFs. Despite the ballistic transport in individual SWCNTs, electrical conductivity of SWCNT networks is limited by low efficiency of charge tunneling between the tube elements. Here, we demonstrate that the nanotube network sheet resistance at high optical transmittance is decreased by more than 50% when fabricated on graphene. This is a comparable improvement as that obtained through gold chloride (AuCl3) doping. However, while Raman spectroscopy reveals substantial changes in spectral features of AuCl3 doped nanotubes, this does not occur with graphene. Instead, temperature-dependent transport measurements indicate that a graphene substrate reduces the tunneling barrier heights, while its parallel conductivity contribution is almost negligible. Finally, we show that combining the graphene substrate and AuCl3 doping, brings the SWCNT thin film sheet resistance down to 36 ω/.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
Aalto University, University of Copenhagen
Journal
ACS Nano
Volume
13
Pages
11522-11529
No. of pages
8
ISSN
1936-0851
DOI
https://doi.org/10.1021/acsnano.9b05049
Publication date
09-2019
Peer reviewed
Yes
Austrian Fields of Science 2012
103018 Materials physics
Keywords
ASJC Scopus subject areas
Materials Science(all), Engineering(all), Physics and Astronomy(all)
Portal url
https://ucris.univie.ac.at/portal/en/publications/enhanced-tunneling-in-a-hybrid-of-singlewalled-carbon-nanotubes-and-graphene(94b1282e-c76a-4bb6-8300-121f13c2b7d0).html