| Abstract
| - Nanoporous films of crystalline anatase with intended application in dye-sensitized photovoltaic cells wereinvestigated by NMR cryoporometry, NMR diffusiometry, electron microscopy, and X-ray diffraction. Thenanoparticles from which the films were subsequently sintered were prepared in two ways, one with an acidicand one with a basic aqueous process environment and along different temperature regimes. The averagemorphology was similar in all films as indicated by the roughly identical 〈2κV/S〉 values where κ is the meancurvature of the pore surface and S/V denotes the surface-to-volume ratio. Self-diffusion of water in the poresis strongly reduced with respect to that of bulk and is influenced both by micrometer-scale obstructions tomolecular displacement and by pore-size effect in pore interconnectivity. The investigated samples exhibitdifferent transport regimes as concerning those phenomena. In this initial study performed on a limited set ofsamples, we found no linear correlation between particle and pore sizes. Instead, total porosity is controlledby particle−particle jamming which, together with particle size polydispersity, may also dominate the effectsthat lead to the observed pore size distributions for the different samples. The rich variation of structuraleffects and transport properties among the few prepared films call for further studies in order to find anoptimal film structure.
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