1. University Malaya Centre for Ionic Liquids, Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
2. Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
3. Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia
4. Solar Energy Research Institute (SERI), University Kebangsaan Malaysia, UKM Bangi 43600, Selangor, Malaysia
5. Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok 16424, West Java, Indonesia