Digestive Ripening: A Fine Chemical Machining Process on the Nanoscale

Abstract

A comprehensive overview of the process of digestive ripening that is known to convert polydisperse nanocrystals to monodisperse ones is presented. Apart from highlighting the role of organic molecules (ligands) in achieving size control, the roles of other parameters such as the nanocrystal-ligand binding strength and the temperature at which the reaction is carried out in accomplishing size control are also delineated. The generality of the procedure is illustrated by providing examples of how it is used to prepare monodisperse nanocrystals of different metals, alloy systems, and ultrasmall nanocrystals and also to narrow the size distribution in complex binary and ternary nanocrystal systems. Finally, the current status as far as the theoretical understanding of how size control is being achieved by digestive ripening is laid out, emphasizing at the same time the necessity to undertake more systematic studies to completely realize the full potential of this practically very useful procedure.

Differences in self‐assembly features of thermoresponsive anionic triblock copolymers synthesized via one‐pot or two‐pot by atom transfer radical polymerization

“…This may be related to the high charge density observed for these moieties at high temperatures. This feature has been reported and discussed previously for uncharged and charged amphiphilic copolymers, and quite recently, an interesting review on this phenomenon was presented . The results for 1 wt% solutions of P2, both with and without salt, show a compression of the intermicellar complexes (R h,s ) as the temperature rises [Fig.…”

The role of nanoparticle size and ligand coverage in size focusing of colloidal metal nanoparticles

“…26,27 In this model (and other models based on LaMer's), 24,25 the temporal separation of nucleation and growth and the diffusion-controlled growth result in narrowing of the size distribution to near monodisperse. Other mechanisms such as oxidative etching (dissolution process due to the presence of structural defects) 28,29 and digestive ripening [30][31][32] (transformation of polydisperse nanoparticles into monodisperse ones, where ligands play major role in the etching process) could also result in controlling the morphology and focusing of the size distribution.…”

A Novel Strategy to Synthesize Dual Blue Fluorescent‐Magnetic EuCl2 Nanocrystals via One‐Pot Method with Controlled Morphologies Using Urea

“…Meanwhile, the evolution and crystallization course of Eu‐nucleus have been investigated deeply via tuning reaction time . TEM images and FFT patterns were used to analyze internal crystalline structure of EuCl 2 NCs at the prolonged reaction time at 260 °C, such as 0.5 min ( Figure A,B), 3 min (Figure C,D), 5 min (Figure E,F), 10 min (Figure G,H), 120 min (Figure I,J), and 180 min (Figure K,L).…”