Selective suspension in aqueous sodium dodecyl sulfate according to electronic structure type allows simple separation of metallic from semiconducting single-walled carbon nanotubes |
| |
Authors: | Kai Moshammer Frank Hennrich Manfred M Kappes |
| |
Affiliation: | 1. Forschungszentrum Karlsruhe, Institut für Nanotechnologie, D-76021, Karlsruhe, Germany 2. Institut für Physikalische Chemie, Universit?t Karlsruhe, D-76128, Karlsruhe, Germany
|
| |
Abstract: | Both density gradient centrifugation and gel electrophoresis have been reported to allow high throughput separation of metallic
from semiconducting single-walled carbon nanotubes (SWNTs) when using aqueous sodium dodecyl sulphate (SDS) suspensions. We
show here that both methods rely on an initial dispersion-by-sonication step, which is already selective with respect to electronic
structure type. The corresponding aqueous SDS “starting” suspensions obtained after sonication and purification by simple
centrifugation (70,000 g, 1 h) contain semiconducting SWNTs primarily in the form of small bundles whereas metallic SWNTs are predominantly suspended
as individual tubes. Density gradient centrifugation then separates the bundles from the individual tubes on the basis of
differences in their overall buoyant densities. Gel electrophoresis separates the longer bundles from the shorter individual
tubes on the basis of their different mobilities. We also demonstrate that such starting suspensions can be fractionated according
to electronic structure type by even simpler techniques such as size exclusion chromatography or gel filtration, thus opening
the way for simple scale-up.
|
| |
Keywords: | Single-walled carbon nanotubes metallic-semiconducting separation electrophoresis density gradient centrifugation size exclusion chromatography |
本文献已被 SpringerLink 等数据库收录! |
|