Formation of Monodispersed Cadmium Sulfide Particles by Aggregation of Nanosize Precursors

TL;DR

This study investigates the formation of monodispersed cadmium sulfide particles through aggregation of nanosized precursors, combining experimental procedures with numerical simulations to confirm a two-stage growth mechanism.

Contribution

It introduces an efficient numerical simulation approach to model colloid formation and confirms the two-stage growth mechanism involving nucleation and aggregation.

Findings

Validated the two-stage growth mechanism

Developed numerical models fitting experimental data

Confirmed nucleation and aggregation as key processes

Abstract

Monodispersed spherical cadmium sulfide particles were used as a model system in order to explain the size selection in the formation of colloids by aggregation of nanosize subunits. Several procedures of mixing the reactants were employed to precipitate these solids and follow the kinetics of particle growth. Efficient numerical simulation techniques for the model rate equations were developed to fit the experimental results. Our results have confirmed the recently proposed mechanism of two-stage growth by nucleation of nanosize crystalline primary particles and their subsequent aggregation into polycrystalline secondary colloids.