Surface and Structures

De-agglomeration and stabilization of nanoparticles
Nanoparticles, because of their extraordinary surface-driven properties, have found applications in a large number of fields. High surface-to-volume ratio and high activity due to the free atoms on their surfaces cause interesting changes in material properties; however, these features are a double-edged sword and often lead to the formation of undesired agglomerates. When agglomerated, nanoparticles lose their outstanding properties; hence, it is essential to break them up prior to use, and to ensure that “de-agglomerated” particles do not re-agglomerate.

This project aims to develop an approach for producing stable core-shell nanoparticles from supplied agglomerated metal oxide nanopowders in a controllable and scalable manner. Core-shell nanoparticles have high potential in heterogeneous catalysis, energy storage, and medical applications. However, on a fundamental level there is currently a poor understanding of how to produce such nanostructured particles in a way that can be controllable and scalable.

Innovatively, the project will be the first study into the breakup of nano agglomeration along with encapsulation of nanoparticles in the gas phase using a continuous PICVD technique in order to produce stable nanoparticles with a sharp size distribution. In this work, an impactor-assisted fluidized bed will be applied to break up the agglomerates, and immediately encapsulate nanoparticles in the gas phase with photoinitiated chemical vapor deposition (PICVD); a technique from the semi-conductor industry combined with the photopolymerization that can deposit a range of organic materials. PICVD used for flat substrates and submicron-droplets offers good control over the polymerization reaction occurs on the surface.