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We have developed a method based upon pulsed laser deposition to produce SrTiO3 nanocrystals embedded in amorphous Lu2O3 high-k dielectric. The high resolution transmission electron microscopy study revealed the complete isolation of SrTiO3 nanocrystals embedded in Lu2O3 matrix with 4 nm diameter and well distributed with an area density estimated to be about 8x 10^11 cm−2. A pronounced capacitance-voltage hysteresis is observed with a memory window of ~1.5 V under the 6 V programming. In addition, the retention characteristics are tested to be robust. Published version

A simple cell architecture that achieves enhanced light harvesting with less dye quantity while simultaneously improving the power conversion efficiency (PCE) of dye-sensitized solar cells is presented. Polystyrene (PS) spheres of sub-micrometer size were incorporated into the titanium dioxide paste resulting in photoanodes with bimodal pore size distribution. Scanning electron micrographs of TiO2 films revealed a mixture of mesoporous and macroporous morphology in which sub-micrometer cavities created by the combustion of PS increased the light scattering, enhancing the optical path length and hence the harvesting of photons by the sensitizer. The amount of dye uptake by these films is lower than that of standard films because the high porosity reduces the total surface area. Even with lower dye adsorption, the photovoltaic performance has been maintained and even improved, mainly due to better open circuit voltage and higher fill factor. Overall, better light harvesting has helped to maintain the efficiency of dye-sensitized solar cells while saving up to 30% of dye loading and replacing the conventional 400 nm scattering layer with voids. By employing these photoanodes, an efficiency of 6.9% was achieved in ionic liquid based dye sensitized solar cells.

The suckers that line the arms and tentacles of squid are equipped with rigid toothed ring-like elements that increase the gripping power during prey capture and handling. The sucker rings of the Humboldt squid Dosidicus gigas, are fully proteinaceous and contain nanotubules with diameters ranging from 100 to 250 nm. It has been shown previously that the ensuing porosity is a prime determinant of the local elastic modulus [A. Miserez et al., Adv. Mater. 21, 401 (2009)]. Here additional nanoindentation data are presented together with structural analyses. The nanomechanical data support our model that the measured modulus is determined by the local porosity. The dry moduli reach ca. 8 GPa and are reduced about two-fold in the hydrated state. This surprisingly small reduction is discussed in relation to possible chemistries responsible for assembly of these structures.