1. Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara, Medan 20155, Indonesia
2. Carbon and Frankincense Research Center, Universitas Sumatera Utara, Medan 20155, Indonesia
3. Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara, Medan 20155, Indonesia
4. Department of Chemistry, Faculty of Mathematics and Natural Sciences, Sam Ratulangi University, Jl. Kampus Unsrat Kleak, Manado 95115, Indonesia
5. Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
6. University Malaya Centre for Ionic Liquids (UMCiL), Universiti Malaya, Kuala Lumpur 50603, Malaysia
7. School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
8. Physics Department, Faculty of Science, Universiti Putra Malaysia, Seri Kembangan 43400, Malaysia
9. Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
10. Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Negeri Medan, Medan 20221, Indonesia
11. Faculty of Applied Sciences, Universiti Teknologi MARA Shah Alam, Shah Alam 40450, Malaysia
12. Research Center for Mining Technology, National Research and Innovation Agency, Jakarta Pusat 10340, Indonesia