Predicting the particle size distribution of silver nanoparticles: coupled PBM-CFD simulations and experimental study*

Extensive experimental and computational work has been performed over the last decades to elucidate the effect of different chemical reagents and reaction operating conditions on the properties of silver nanoparticles (AgNPs) for different applications.  However, despite all these efforts, it is still very challenging to predict the final properties of AgNPs. 

In this work, the synthesis of AgNPs is investigated via a coupled population balance model and computational fluid dynamics (PBM-CFD) approach which aims to predict the temporal evolution and particle size distribution (PSD) for two different synthesis protocols in a well-mixed reactor and a T-junction microfluidic device.  The nucleation and growth kinetic constants were calculated from UV-vis measurements at 400 nm, characteristic for AgNPs through the Finke-Watzky two-step mechanism, typically used to describe metal-nanoparticles synthesis. PBM results are validated against experiments, in terms of silver ion concentration and PSD at different operating conditions. It is shown that under perfect mixing conditions, the PSD can be reliably predicted.