Zeolites microheterogeneity

What is the structure and the dynamics of hydrated/solvated electron in hot/supercritical water In dispersed clusters of polar liquids in nonpolar liquids In microheterogeneous media (e.g. water clusters in zeolite cavities) In mixed and complex solvents of practical importance (e.g. Ref. 107) on surfaces ... 

Electron-transfer Processes in Zeolites and Related Microheterogeneous Media... 

FIGURE 1.8 CV for a PIGE modified with a microheterogeneous deposit of zeolite Y. Potential scan rate, 50 mV/sec. 

Microheterogeneous electrocatalysis can be performed with zeolite-based catalysts using suspensions of such materials in organic solvents with low ionic strength by applying a DC voltage to suspensions of zeolite particles, as described by Rolison and Stemple (1993) for the Pd"-Cu"-NaY catalyzed oxidation of propene, but a wide variety of systems has been studied. 

Bessel, C.A., and Rolison, D.R. 1997b. Microheterogeneous dispersion electrolysis with nanoscale electrode-modified zeolites. Journal of Electroanalytical Chemistry 439, 97-105. 

In classical, continuum theories of diffusion-reaction processes based on a Fickian parabolic partial differential equation of the form, Eq. (4.1), specification of the Laplacian operator is required. Although this specification is immediate for spaces of integral dimension, it is less straightforward for spaces of intermediate or fractal dimension [47,55,56]. As examples of problems in chemical kinetics where the relevance of an approach based on Eq. (4.1) is open to question, one can cite the avalanche of work reported over the past two decades on diffusion-reaction processes in microheterogeneous media, as exemplified by the compartmentalized systems such as zeolites, clays and organized molecular assemblies such as micelles and vesicles (see below). In these systems, the (local) dimension of the diffusion space is often not clearly defined. 

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