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Updated: Jun 4, 2026
Compact Quantum Dots for Single-molecule Imaging
Published on: October 9, 2012
Role of surface ligands in optical properties of colloidal CdSe/CdS quantum dots
Zhijun Ning1, Matyas Molnár, Yun Chen
1Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, Stockholm, Sweden.
Abstract:
In order to study the role of surface ligands in determining optical properties of colloidal quantum dots (QDs), we have selectively fabricated and studied CdSe/CdS core-shell QDs with strongly confined electron and hole states attached with commonly used surface ligands. Optical properties, viz. absorption and fluorescence of these QDs, are characterized from which salient changes have been observed for different ligand substitutions which, through theoretical analysis, can be associated with electronic structure properties of the QD-ligand composite systems, in particular localization of wave functions of electrons and holes in the QDs and the band matching of the HOMO-LUMO gap of the ligands. The findings can be utilized to facilitate the understanding and optimization of properties of QD biomarkers with functionalizing surface ligands for targeting cellular objects.
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