title: Reversible dispersion and release of carbon nanotubes using foldable oligomers.
abstract: Foldamers are synthetic and designable oligomers that adopt a conformationally ordered state in selected solvents. We found that oligo(m-phenylene ethynylene)s, which are single-stranded foldamers, can be made to reversibly disperse and release single-walled carbon nanotubes (SWCNTs) simply by changing the solvent, consistent with a change from an unfolded state to a folded state. Using absorption spectroscopy, atomic force microscopy, Raman spectroscopy, and electrical measurements, we observed that the foldamer-dispersed SWCNTs are individually well-dispersed and have a strong interfacial interaction with the foldamers. In contrast, the released SWCNTs appeared to be free of foldamers. Under illumination, transistors based on the foldamer-dispersed SWCNTs demonstrated significant photoresponse, apparently due to photoinduced charge transfer between the foldamers and SWCNTs. The reported nanocomposites may open an alternative way of developing optoelectronic devices or sensors based on carbon nanotubes.
authors.affiliation: Department of Materials Science and Engineering, The University of Utah, Salt Lake City, Utah 84108, USA.
authors.forename: Zengxing
authors.initials: Z
authors.lastname: Zhang
authors.forename: Yanke
authors.initials: Y
authors.lastname: Che
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Smaldone
authors.forename: Miao
authors.initials: M
authors.lastname: Xu
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Bunes
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Moore
authors.forename: Ling
authors.initials: L
authors.lastname: Zang