Circular dichroism of surface complexes based on quantum dots and azo dye

May 22, 2018

Title

Circular dichroism of surface complexes based on quantum dots and azo dye

Author

Evgeny V. Kundelev, Anna O. Orlova, Vladimir G. Maslov, Alexander V. Baranov, Anatoly V. Fedorov

Year

2017

Journal

Chirality

Abstract

Chiral properties of surface complexes based on CdSe/ZnS quantum dots (QDs) and 1-(2-pyridylazo)-2-naphthol (PAN) azo dye were investigated by circular dichroism spectroscopy. The use of L-, D-cysteine (Lcys, Dcys) capping ligands allowed us to obtain water-soluble chiral QD-PAN complexes. The characterization of the complexes was performed by UV-vis, FTIR, and CD spectroscopy. Quantum chemical TDDFT calculated CD spectra reproduced the experimentally observed sign patterns, which originate from binding Lcys or Dcys and PAN molecules to the same Zn atom on the QD surface. The resulting complex is characterized by a large circular dichroism in comparison with an ordinary QD chirality induced by cysteine molecules. The pattern of CD signal is the same for Lcys and Dcys ligands in chiral QD-PAN complex.

Instrument

J-1500

Keywords

Circular dichroism, Nanostructures, Stereochemistry, Materials