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CSP technology has a huge potential. However, all the components used in the energy generation process are not yet optimized. Reflectors are one of the most important devices to improve, as the efficiency of the power plant is directly linked to their high performance. Because reflectors are costly and cannot be changed frequently, their reflectivity should be maintained as long as possible. For this reason it is important to study their durability under real operation weather conditions. Natural ageing allows the determination of real lifetime mirrors characteristics and better understanding of their degradation mechanisms. For this investigation, polymeric and glass mirrors were exposed in two Moroccan sites with characteristic weather conditions, one close to the ocean and one in the desert, for more than one year of natural ageing. Different characterization techniques such as optical microscopy and UV-Visible-NIR spectophotometry were used to detect and analyze degradation mechanisms. The obtained results are shown in this paper and a comparison of mirrors behavior is proposed depending on the outdoor exposure sites. It can be noted that the desertic conditions are less aggressive than coastal conditions regarding to physico-chemical degradation of both investigated mirror materials.

C@Na3V2(PO4)2F3 samples were obtained by using Cetyl Trimethyl Ammonium Bromide (CTAB) as a surfactant. The optimization of the added amount allowed controlling the eventual nanometric morphology of the particles. The morphological and structural properties of these samples were discussed in the light of solid-state techniques as X-ray diffraction, Raman and XPS spectroscopies, and electron microscopy. Galvanostatic test in sodium half-cells revealed that the nanometric spherical and porous particles provided by the addition of intermediate amounts of CTAB showed excellent cycling stability and superior high rate capability reflected in the minimization of the cell polarization and the determination of a high apparent diffusion coefficient.

The synthesis, structural characterization, and electrochemical evaluation as potential anode material for Li ion battery of new materials based on tin phosphate are studied. Hydrothermal treatments of tin halides are used for the preparation of phosphate oxysalts. 119 Sn Mo ¨ssbauer spectroscopy is used to discern the oxidation state of tin in the synthesized materials. Samples prepared with SnCl 2 have better electrochemical properties than those prepared with SnF 2 . Also, low concentration favors the formation of nanostructured materials with an improved capacity retention and high specific capacity. Capacities higher than 500 mAhg -1 are observed after 40 cycles for the ex-SnCl 2 nanoparticulate sample.

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