1. Center for Advanced Materials, Qatar University, Doha, Qatar
2. Department of Civil and Environmental Engineering, Materials Engineering Centre, University of Perugia, Terni, Italy
3. Department of Physics, S. B. College, Changanacherry, Kerala, India
4. School of chemical sciences & International and Interuniversity Centre for Nanoscience and Nanotechnology, Mahatma Gandhi University, Kottayam, Kerala, India