@article {45357, title = { Ligand-solvent compatibility: the unsung hero in the digestive ripening story}, journal = {Langmuir }, volume = {34}, year = {2018}, month = {NOV}, pages = {13680-13689}, type = {Article}, abstract = {

Digestive ripening (DR) is a process where a polydisperse nanocrystal (NC) system is converted into a monodisperse one with the aid of thermal heating of NCs in the presence of an excess surface-active organic ligand called digestive ripening agent (DRA) and a solvent. Here, we demonstrate that the solvent-DRA compatibility influences the final size and size distribution of the NCs in a significant manner. Accordingly, in this study, using the DR of gold NCs as the test case with alkanethiol (decanethiol/C10HT) and fluorinated thiol (1H,1H,2H,2H-perfluorodecanethiol/C10FT) as DRA{\textquoteright}s and toluene and alpha,alpha,alpha-trifluoro-toluene (TFT) and their combination as solvents, we clearly establish that alkanethiols result in best-quality NCs after DR in toluene while the fluorinated thiols provide reasonably monodispersed NCs in TFT. Our results also ascertain that even when DR is carried out in a mixture of solvents, as long as the compatible solvent is the major component, the DR process results in reasonably monodisperse NCs. As soon as the amount of uncompatible solvent exceeds a threshold limit, there is perceptible increase in the polydispersity of the NCs. We conclude that the polarity of the solvent, which affects the buildup of ligated atoms/clusters, plays a key role in controlling the size distributions of the NCs.

}, issn = { 0743-7463}, doi = {10.1021/acs.langmuir.8b02699}, author = {Shimpi, Jayesh R. and Chaudhari, Vijay Raman and Prasad, Bhagavatula L. V.} }