1. Laboratory Physical-Chemistry of Solid State, University of Sfax, Faculty of Sciences of Sfax, Tunisia, BP 802, Route de Soukra, 3018 Sfax, Tunisia
2. Unit of Materials and Environment (UR15ES01), IPEIT, University of Tunis, 2 rue Jawaher Lel Nahru, 1089 Montfleury, Tunisia
3. Laboratory of Spectroscopic Characterization and Optical Materials, Faculty of Sciences, University of Sfax, B.P. 1171, Sfax 3000, Tunisia
4. Univ. Bordeaux, CNRS, Bordeaux INP, ICMCB, UMR 5026, F-33600 Pessac, France