Abstract
Intermolecular carbon nanotube junctions were formed by coupling chemically functionalized nanotubes with molecular linkers. An end-to-side or end-to-end heterojunction can be formed by reacting chloride terminated nanotubes with aliphatic diamine. The chemically modified nanotube mats were characterized by Raman spectroscopy. The peak shift in the tangential vibration mode reveals that the attached chemical functional groups can behave as either an electron donor or an acceptor, and facilitate charge transfer with the nanotube host. The charge transfer is also verified by transport measurements on individual end-to-side intermolecular junctions, which show diode-like behavior. The charge transfer can be attributed to amide functionality at the junction. © 2002 American Institute of Physics.