1. Qatar Environment and Energy Research Institute, Hamad bin Khalifa University,Doha,Qatar
2. Institute for Nanostructures, Nanomodelling and Nanofabrication, University of Aveiro,Department of Physics and i3N,Aveiro,Portugal,3810-193
3. Indian Institute of Technology Roorkee,Department of Physics,Roorkee,Uttarakhand,India,247667