1. Department of Chemistry and Centre for Research and Development, KPR Institute of Engineering and Technology, Coimbatore 641407, Tamilnadu, India
2. National Centre for Nanoscience and Nanotechnology, University of Madras, Chennai 600025, India
3. Department of Physics, Bharathiar University, Coimbatore 641046, India
4. DRDO-Life Sciences, Bharathiar University, Coimbatore 641046, India