Authors: M. Olek, T. Büsgen, J. van Embden, M. Hilgendorff, P. Mulvaney and M. Giersig
Affilation: CAESAR, Germany
Pages: 210 - 213
Keywords: carbon nanotubes, quantum dots, heterostructures, luminescence
The key advantage of our research is a noninvasive functionalization of carbon nanotubes, which ensures good dispersion and stability of carbon nanotubes (CNT) in a vast range of organic and inorganic solvents. The method can be efficiently applied for the large scale preparation of solubilized carbon nanotubes in a very simple way and further allows an easy attachment of various kinds of colloidal nanoparticles. In this manner, we present a new approach for the preparation of multiwall carbon nanotubes - quantum dots (MWNT/QDs) heterostructures with a highly defined morphology. The structural and optical properties of CNT/QD heterostructures are characterized by electron microscopy and photoluminescence (PL) spectroscopy. QDs on bare MWNT were found to exhibit no luminescence while the QD/SiO2/MWNT composites retained their luminescence. We assume that interactions between MWNTs and QDs involve charge transfer of photoexcited electrons from the conductive band of the donor (QDs) to the empty electronic states of the acceptor (MWNTs) resulting in non-radiative decay of the QD excited state.