title: Efficient spectrofluorimetric analysis of single-walled carbon nanotube samples.
abstract: A new method and instrumentation are described for rapid compositional analysis of single-walled carbon nanotube (SWCNT) samples. The customized optical system uses multiple fixed-wavelength lasers to excite NIR fluorescence from SWCNTs individualized in aqueous suspensions. The emission spectra are efficiently captured by a NIR spectrometer with InGaAs multichannel detector and then analyzed by a computer program that consults a database of SWCNT spectral parameters. The identities and relative abundances of semiconducting SWCNTs species are quickly deduced and displayed in graphs and tables. Results are found to be consistent with those based on manual interpretation of full excitation-emission scans from a conventional spectrofluorometer. The new instrument also measures absorption spectra using a broadband lamp and multichannel spectrometers, allowing samples to be automatically characterized by their emission efficiencies. The system provides rapid data acquisition and is sensitive enough to detect the fluorescence of a few picograms of SWCNTs in ~50 μL sample volumes.
authors.affiliation: Department of Chemistry and Richard E. Smalley Institute for Nanoscale Science and Technology, Rice University, 6100 Main Street, Houston, Texas 77005, USA.
authors.forename: John-David R
authors.initials: JD
authors.lastname: Rocha
authors.forename: Sergei M
authors.initials: SM
authors.lastname: Bachilo
authors.forename: Saunab
authors.initials: S
authors.lastname: Ghosh
authors.forename: Sivaram
authors.initials: S
authors.lastname: Arepalli
authors.forename: R Bruce
authors.initials: RB
authors.lastname: Weisman
mesh_terms: D001152:Arsenicals / Q000737:chemistry; D005453:Fluorescence; D005708:Gallium / Q000737:chemistry; D007204:Indium / Q000737:chemistry; D007834:Lasers; D037742:Nanotubes, Carbon / Q000032:analysis*; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation / Q000379:methods
chemical_list: D001152:Arsenicals; D037742:Nanotubes, Carbon; D007204:Indium; C043055:gallium arsenide; D005708:Gallium