Transparent conductive single-walled carbon nanotube networks with precisely tunable ratios of semiconducting and metallic nanotubes.
We present a comprehensive study of the optical and electrical properties of transparent conductive films made from precisely tuned ratios of metallic and semiconducting single-wall carbon nanotubes. The conductivity and transparency of the SWNT films are controlled by an interplay between localized and delocalized carriers, as determined by the SWNT electronic structure, tube-tube junctions, and intentional and unintentional redox dopants. The results suggest that the main resistance in the SWNT thin films is the resistance associated with tube-tube junctions. Redox dopants are found to increase the delocalized carrier density and transmission probability through intertube junctions more effectively for semiconductor-enriched films than for metal-enriched films. As a result, redox-doped semiconductor-enriched films are more conductive than either intrinsic or redox-doped metal-enriched films.
Blackburn
Jeffrey L
JL
National Renewable Energy Laboratory, Golden, Colorado 80401, USA. jeffrey_blackburn@nrel.gov
Barnes
Teresa M
TM
Beard
Matthew C
MC
Kim
Yong-Hyun
YH
Tenent
Robert C
RC
McDonald
Timothy J
TJ
To
Bobby
B
Coutts
Timothy J
TJ
Heben
Michael J
MJ
D003198:Computer Simulation; D003460:Crystallization / Q000379:methods*; D004553:Electric Conductivity; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008670:Metals / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D012031:Refractometry; D012666:Semiconductors; D013499:Surface Properties
D046911:Macromolecular Substances; D008670:Metals; D037742:Nanotubes, Carbon