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High solar performance Zr-ZrO 2 cermet solar coatings were designed using a numerical computer model and deposited experimentally. The layer thickness and Zr metal volume fraction for the Zr-ZrO 2 cermet solar selective coatings on a Zr or Al reflector with a surface ZrO 2 or Al 2 O 3 anti-reflection layer were optimized to achieve maximum photo-thermal conversion efficiency at 80˚C under concentration factors of 1-20 using the downhill simplex method in multi-dimensions in the numerical calculation. The dielectric function and the complex refractive index of Zr-ZrO 2 cermet materials were calculated using Sheng's approximation. Optimization calculations show that Al 2 O 3 /Zr-ZrO 2 /Al solar coatings with two cermet layers and three cermet layers have nearly identical solar absorptance, emittance and photo-thermal conversion efficiency that are much better than those for films with one cermet layer. The optimized Al 2 O 3 /Zr-ZrO 2 /Al solar coating film with two cermet layers has a high solar absorptance value of 0.97 and low hemispherical emittance value of 0.05 at 80˚C for a concentration factor of 2. The Al 2 O 3 /Zr-ZrO 2 /Al solar selective coatings with two cermet layers were deposited using dc magnetron sputtering technology. During the deposition of Zr-ZrO 2 cermet layer, a Zr metallic target was run in a gas mixture of argon and oxygen. By control of oxygen flow rate the different metal volume fractions in the cermet layers were achieved using dc reactive sputtering. A solar absorptance of 0.96 and normal emittance of 0.05 at 80˚C were achieved.

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Ag/TiO 2 nano thin films was found to be efficient and green heterogeneous catalyst for the synthesis of dihydropyrano [2,3-c]pyrazole derivatives via a one-pot three-component reaction between 3-methyl-1H-pyrazol-5(4H)-one or 3-methyl-1(phenyl)-pyrazol-5(4H)-one, aldehydes and malononitrile at room temperature. Ag/TiO 2 and TiO 2 films were prepared by spray pyrolysis technique and the effect of substrate temperature and silver incorporation on optical, morphological and structural properties were investigated by XRD, AFM, spectrophotometry and photoluminescent spectroscopy. The results of this study shows adding of Ag to TiO 2 films increased the optical absorption due to plasmonic behavior of Ag free electrons. XRD analysis was revealed the Hexagonal structure with Anatase phase and 101 prefer crystal orientation which is prefer phase for photocatalyst applications.