a b s t r a c tThe nanocrystalline ZnO:Fe semiconductor oxides were successfully synthesized via the sol-gel calcination method. Structural, optical and electrical properties of the investigated samples were characterized by various techniques such as atomic force microscopy (AFM), UV-vis absorption and electrical transport measurements. The optical band gap for undoped ZnO (3.19 eV) decreases (2.75 eV) with increasing Fe-doped ZnO (20%). The temperature dependences of the electrical conductivities of undoped ZnO and Fe-doped ZnO were measured and analyzed by Arrhenius equation. The electrical conductivity of the samples decreases with the increase of Fe doping ratio; hence, the electrical conductivity mechanism is controlled by thermally activated processes. To support the nanostructure of Fe-doped ZnO, AFM micrographs were performed.

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a b s t r a c tLuminescent solar concentrator (LSC) films based on Polymethylmethacrylate (PMMA) nanohybrids were prepared using free radical polymerization of MMA incorporated with oxide nanoparticles; SiO 2 , ZnO and TiO 2 . The effect of nano-oxide type was studied by Fourier transform infrared spectroscopy (FT-IR), UV eVis absorption and fluorescence spectroscopy measurements. The performance of LSC nanohybrid films was evaluated and optimized for photoselective greenhouse cladding applications in order to increase the plant productivity by changing the solar spectrum. It was found that ZnO nanohybrid LSC film had offered the best spectral properties for photosynthetic active radiation besides their excellent resistance to photo and thermal degradation especially in hot countries like KSA. Regarding thermal efficiency, the highest infrared (IR) efficiency has been found for silica nanohybrid LSC film, which reached about 83%. This result is promising to improve thermal efficiency in greenhouse claddings in cold regions and thermal covering systems like solar dryers and solar desalination systems.