Ternary Chalcogenide-Based Quantum Dots and Carbon Nanotubes: Establishing a Toolbox for Controlled Formation of Nanocomposites

Abstract

A general procedure based on electrostatic self-assembly for preparing nanocomposites based on carbon nanotubes (CNTs) and ternary chalcogenide semiconductor nanoparticles is shown. This was achieved by surface functionalization of the single components through well-established protocols, for CNTs, and a transferable general strategy for the nanoparticles. Heterostructures were then synthesized through electrostatic interaction between oppositely charged components. Structural, colloidal, and optical properties were characterized by transmission electron microscopy, X-ray diffraction, infrared spectroscopy, dynamic light scattering, ζ-potential, and absorption- and (time-resolved) photoluminescence measurements. Interestingly, the nanocomposites showed a blue shift in their excitation and emission spectra when compared to the pure nanoparticles but only when analyzed in powder form. Further investigations in the form of density functional theory (DFT) calculations were performed to evaluate the origin of the change in the optical properties.