Nucleation-growth type kinetic models of nanoparticle formation: ordinary and partial differential equations

2019. 04. 23. 12:15
Gábor Lente (University of Pécs)

Nanoparticles are widely used and studied in today's chemistry, especially in the field of catalysis. Recently, most of the research focus has been given to metal (mostly noble metals) or semiconductor (oxide or sulfide) nanoparticles, which usually contain a few hundred or a few thousand atoms. This size means that the number of particles on the overall surface is not negligible compared to the number of those inside the particles, which results in unique properties that do not resemble those of macroscopic phases or individual particles, either. From the point of view of applications, controlling the average size and the size distribution of nanoparticles is a key aspect during synthesis. As nanoparticles are generally thermodynamically unstable relative to the bulk solid state, the size is primarily governed by kinetic factors. Therefore, a rational, designed synthesis method must be based on a suitable kinetic model.

The lecture will introduce a class of deterministic kinetic models that rely on spontaneous or induced nucleation (the formation of a seed from a few monomeric units) and nanoparticle growth (the addition of a single monomeric unit to an existing nanoparticle). In one case, the solution of the resulting set of simultaneous ordinary differential equations was found. A general approximation strategy using partial differential equations will also be presented.  

Az előadás a Formális reakciókinetikai szeminárium előadása.