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Updated: Mar 12, 2026

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles
Published on: March 2, 2016
In situ spectroscopic characterization of a solution-phase X-type ligand exchange at colloidal lead sulphide quantum
D M Kroupa1, N C Anderson2, C V Castaneda2
1Chemistry & Nanoscience Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA. matt.beard@nrel.gov and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309, USA.
Abstract:
We employed quantitative NMR spectroscopy and spectrophotometric absorbance titration to study a quantum dot X-type ligand exchange reaction. We find that the exchange is highly cooperative, where at low extents of exchange the change in free energy of the reaction, ΔGXC, is ∼11 kJ mol-1 while at higher extents of exchange ΔGXC saturates to ∼-4 kJ mol-1. A modified Fowler binding isotherm is developed to describe the reaction.

