1. College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Jiangjun Avenue, 211106 Nanjing, China
2. Department of Physics, University of Okara, 2 KM Multan Road Renala Khurd By Pass, 401241 Okara, Pakistan
3. Department of Chemistry, University of Okara, 2 KM Multan Road Renala Khurd By Pass, 401241 Okara, Pakistan