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A nanosilver (nano-Ag)/poly(vinyl alcohol) (PVA) hydrogel device was synthesized with c irradiation because it is a highly suitable tool for enhanced nano-Ag technologies and biocompatible controlled release formulations. The amount of the Ag 1 ions released in vitro by the nano-Ag/PVA hydrogel device was in the antimicrobial parts per million concentration range. The modeling of the Ag 1 ion release kinetics with the elements of the drug-delivery paradigm revealed the best fit solution (R 2 > 0.99) for the Kopcha and Makoid-Banakar's pharmacokinetic dissolution models. The term A/B, derived from the Kopcha model, indicated that the nano-Ag/PVA hydrogel was mainly an Ag 1 -ion diffusion-controlled device. Makoid-Banakar's parameter and the short time approximated Ag 1 -ion diffusion constant reflected the importance of the size of the Ag nanoparticles. However, it appeared that the cell oxidation potential of the Ag nanoparticles depended on the diffusion characteristics of the fluid penetrating into the Ag/PVA nanosystem.

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Producing green and efficient energy sources is a major challenge. As a consequence, the use of photovoltaic devices for conversion of light into electricity is growing worldwide. A lot of effort had been invested to create high-efficient solar cells, but their durability, stability, flexibility and efficiency at low light intensities are still unexplored. Here, we built a flexible solar cell made of p-doped, amorphized a-undoped and n-doped Sb 2 S 3 solid carrier loaded with electrolyte. Indium tin oxide glass was the working electrode, and aluminium was the counter electrode. Every (p-a-n) flexible Sb 2 S 3 /solid carrier layers were obtained using a cheap casting/solvent evaporation technique, from a blend consisted of chitosan, polyethylene glycol and electrolyte containing 0.5 M potassium iodide and 0.05 M iodine, and corresponding synthesized amorphized a-undoped and p and n-doped Sb 2 S 3 semiconductor.Results show that flexible Sb 2 S 3 solar cell possesses good stability and efficiency of about 10% at 5% sun. Overall, our findings demonstrate for the first time that flexible solar cell can be made and used for low light intensity applications.

To produce well‐defined metal clusters stabilized in protective matrix, poly(N‐isopropylacrylamide) (PNiPAAm) hydrogel with different initial concentration of polymer was used as nanoreactor. The in situ synthesis of well dispersed silver nanoparticles (AgNPs) was performed by gamma irradiation. The obtained AgNPs are spherical in shape with the diameter less than 20 nm. Crystalline properties of nanoparticles such as size, texture coefficient, strain, stress, lattice parameter, d‐spacing, and dislocation density have been calculated using XRD data. Results confirm that the changes of lattice parameter of crystalline AgNPs sensitively reflect their state of strain and stress depending on the formation conditions (i.e., on the concentration of PNiPAAm) and on the diameter of AgNPs. The negative lattice strain and compression stress were observed for the smaller AgNPs (lattice contraction), while for the larger AgNPs are positively strained and under tensile stress (lattice expansion). XPS spectra revealed the donor‐acceptor type of interaction between carbonyl oxygen from PNiPAAm and AgNPs (positive shift of high BE component of O 1s and negative shift of Ag 3d BE). The greater dislocation density of smaller AgNPs incorporated in more concentrated PNiPAAm, resulted in more binding sites and stronger interaction with polymer. POLYM. COMPOS., 38:1014–1026, 2017. © 2015 Society of Plastics Engineers

Summary We present here a novel solar cell made of ITO/composite p‐doped Sb2S3 + P3HT + PANI+TiO2/amorphous Sb2S3 + P3HT + PANI + TiO2/n‐doped Sb2S3 + P3HT + PANI + TiO2/solid carrier/aluminum as counter electrode. With spraying technique, the layers were deposited and the thickness of films was 1 μm. A new solid carrier of electrolyte was a blend consisted of chitosan (low MW), polyethylene glycol and electrolyte. X‐ray diffraction was recorded to confirm the amorphous nature of the blend. Information about the surface appearance and roughness of a solid carrier dry and soaked in the electrolyte was given by atomic force microscopy. The solar cell was examined at very low and low light intensity (5% and 35% of sun, respectively), and at standard test conditions (100% of sun) using different light sources. The whole cell surface was 7.5 cm2 while the illuminated part was 3 cm2. Obtained results expressed for the illuminated surface showed the highest efficiency of 23.1% at 5% of sun while the efficiency of the cell was 2.9% at 35% of sun and only 0.75% at intensity of 100% of sun.