CdSe–stearates nanocrystal–
ligands complex as a whole possess strongly temperature- and size-dependent yet well-defined solubi
lity in small organic solvents, which shows
little solvent effects as long as the complexes remained intact. A quantitative thermodynamic model is developed to describe such solubi
lity behavior, which differs fundamentally from conventional models for micron colloids. The model reveals that the conformation entropy of the
n-alkanoate chain released in dissolution greatly stabi
lize the colloidal solution but the strong chain–chain interdigitation between adjacent particles in so
lid diminishes the solubi
lity. These understandings result in “entropic
ligands” (see full disclosure in another report (
10.1021/acs.nanolett.6b00730)) as the universal means to battle processability challenges of colloidal nanocrystals.