Chiral CdTe Quantum Dots

Abstract

AbstractQuantum dots (QDs) are fluorescent semiconductor (e.g. II-VI) nanocrystals, which have a strong characteristic spectral emission. This emission is tunable to a desired energy by selecting variable particle size, size distribution and composition of the nanocrystals. QDs have recently attracted enormous interest due to their unique photophysical properties and range of potential applications in photonics and biochemistry.The main aim of our work is develop new materials based chiral quantum dots (QDs) and establish fundamental principles influencing the structure and properties of chiral QDs. Here we report the quantum efficiency control in cysteine capped CdTe quantum dots (QDs) by varying ratios of enantiomeric stabilizers. We also demonstrate that the circular dichroism (CD) of CdTe QDs can be introduced by utilizing the mixture of penicilamine and cysteine stabilizers of the same chirality. This approach results in QDs with the enhanced CD activity, but causes a decrease in the quantum yield and widening of the emission due to the presence of chiral defects at the nanoparticle surface. We believe that these new QDs could find important applications as fluorescent assays and sensors (or probes) in asymmetric synthesis, catalysis, enantioseparation, biochemical analysis and medical diagnostics.