Real Time Hyperspectroscopy for Dynamical Study of Carbon Nanotubes

Photoluminescence excitation mapping used routinely to characterize semiconducting single-walled carbon nanotubes (sc-SWCNTs) is extended to provide time-dependent data. A hyperspectral method based on a supercontinuum light source and an imaging detector is demonstrated with excitation and emission wavelengths spanning 600-1000 and 1050-1650 nm, respectively, at time scales <100 ms. An example of a titration experiment is given to highlight the potential offered by the technique. Specifically, the dependence of luminescence yield on acceptor concentration is tracked for 18 different chirality assigned sc-SWCNT species. Dopant-induced quenching presents a simple dependence on nanotube diameter, with larger diameter being most affected, while chirality does not appear to be a dominant factor. In a second example, the successive addition of acceptor and donor molecules leads to a modulation of luminescence intensity upon hole doping and dedoping.