The electrical properties of nanostructured, heavily yttria‐ or samaria‐doped ceria ceramics are studied as a function of grain size using electrochemical impedance spectroscopy (EIS). A remarkable enhancement in the total ionic conductivity of about one order of magnitude is found in nanostructured samples, compared with the intrinsic bulk conductivity of conventional microcrystalline ceramics. This effect is attributed to the predominance of grain‐boundary conduction in the nanostructured materials, coupled with an increase in the grain‐boundary ionic diffusivity with decreasing grain size.

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Expanding mesopore size beyond a 10 nm diameter is a big challenge for developing applications based on mesostructured-mesoporous thin films, especially in nanobiotechnology. This triggers the need of new multipore materials produced by reproducible soft chemistry routes. We present here a novel and simple one-pot synthesis method that allows the creation of a new kind of hierarchically porous thin film using a combination of supramolecular templating and phase separation. Accurate tuning of pore size distribution (bimodal, with small mesopores 13-18 nm diameter, and large pores 20-150 nm diameter) is attained by controlling the solubility of a pore enhancement agent, poly (propylene glycol), in the presence of a co-solvent. The reported strategy permits the in situ tuning of the processes that govern the pore generation at different length scales; this opens a path for fabrication of multimodal mesoporous films, which represents an important breakthrough in the field.

The fluid-front dynamics resulting from the coexisting infiltration and evaporation phenomena in nanofluidic systems has been investigated. More precisely, water infiltration in both titania and silica mesoporous films was studied through a simple experiment: a sessile drop was deposited over the film and the advancement of the fluid front into the porous structure was optically followed and recorded in time. In the case of titania mesoporous films, capillary infiltration was arrested at a given distance, and a steady annular region of the wetted material was formed. A simple model that combines Lucas-Washburn infiltration and surface evaporation was derived, which appropriately describes the observed filling dynamics and the annulus width in dissimilar mesoporous morphologies. In the case of wormlike mesoporous morphologies, a remarkable phenomenon was found: instead of reaching a steady infiltration-evaporation balance, the fluid front exhibits an oscillating behavior. This complex filling dynamics opens interesting possibilities to study the unusual nanofluidic phenomena and to discover novel applications.