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 super-continuum light source and an imaging detector is demonstrated with excitation and emission wavelengths spanning 600-1000 nm and 1050-1650 nm, respectively, at timescales less than 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 of addition of acceptor and donor molecules leads to a modulation of luminescence intensity upon hole doping and de-doping.