1. Optical Materials and Bioimaging Research Laboratory, Department of Applied Physics
2. Indian Institute of Technology (Indian School of Mines)
3. Dhanbad-826004
4. India
5. Department of Physics
6. Nano Photonics Laboratory, Department of Applied Physics
7. Indian Institute of Technology Guwahati
8. Guwahati-781039
9. University of Free State
10. Bloemfontien-9300
11. South Africa
12. School of Chemistry and Chemical Engineering
13. Yulin University
14. Yulin 719000
15. P. R. China
16. Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization