1. School of Materials Science and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
2. Department of Chemistry, DDU Gorakhpur University, Gorakhpur 273009, India
3. Department of Chemistry, K. N. Govt. P. G. College Gyanpur, Bhadohi 221304, India
4. Department of Physics, National Institute of Technology, Jamshedpur 832109, India