Functionalization of single-wall carbon nanotubes with chromophores of opposite internal dipole orientation.
We report the functionalization of carbon nanotubes with two azobenzene-based chromophores with large internal dipole moments and opposite dipole orientations. The molecules are attached to the nanotubes noncovalently via a pyrene tether. A combination of characterization techniques shows uniform molecular coverage on the nanotubes, with minimal aggregation of excess chromophores on the substrate. The large on/off ratios and the subthreshold swings of the nanotube-based field-effect transistors (FETs) are preserved after functionalization, and different shifts in threshold voltage are observed for each chromophore. Ab initio calculations verify the properties of the synthesized chromophores and indicate very small charge transfer, confirming a strong, noncovalent functionalization.
Department of Physics, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
Yuanchun
Y
Zhao
Changshui
C
Huang
Myungwoong
M
Kim
Bryan M
BM
Wong
François
F
Léonard
Padma
P
Gopalan
Mark A
MA
Eriksson
D001391:Azo Compounds / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011721:Pyrenes / Q000737:chemistry; D014173:Transistors, Electronic
D001391:Azo Compounds; D037742:Nanotubes, Carbon; D011721:Pyrenes; C030984:pyrene; C009850:azobenzene