Scientific Achievement
For reshaping of facetted metal nanocrystals, involving nucleation and growth of new outer layers, we show that classical nucleation theory (CNT) fails to describe behavior. Instead a successful master equation theory is developed.
Significance and Impact
Shape stability is critical for nanocrystals synthesized with facetted non-equilibrium shapes to optimize performance for catalysis, etc. This prompted our development of an appropriate theory for the cooperative many-atom reshaping process to elucidate behavior & aid experiment.
Research Details
- KMC simulation of a stochastic model for nanocrystal reshaping mediated by surface diffusion quantifies reshaping.
- Constrained equilibrium MC simulation for the free energy profile during reshaping reveals the failure of CNT.
- Our master equation treatment incorporating key nanocrystal configurations succeeds in describing the reshaping barrier.
Article Link: https://doi.org/10.1063/5.0138266