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arXiv · 1307.4428

Selective nucleation in porous media

Lester O. Hedges·Stephen Whitelam
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Abstract

Geometrical arguments suggest that pore-mediated nucleation happens in general in a two-step fashion, the first step being nucleation within the pore, the second being nucleation from the filled pore into solution [Page & Sear, Phys. Rev. Lett. 97, 65701 (2006)]. The free energy barriers controlling the two steps of this process show opposite dependencies on pore size, implying that for given thermodynamic conditions there exists a pore size for which nucleation happens fastest. Here we show, within the two- and three-dimensional Ising lattice gas, that this preferred pore size tracks the size of the bulk critical nucleus, up to a numerical prefactor. This observation suggests a simple prescription for directing nucleation to certain locations within heterogeneous porous media.

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Lester O. Hedges, Stephen Whitelam. 2013-07-16. Selective nucleation in porous media. https://doi.org/10.1039/c3sm51946e

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