1. Functional Devices Laboratory, Institute of Advanced Technology, Universiti Putra Malaysia (UPM), 43400 Serdang, Selangor, Malaysia
2. Department of Chemistry and Biology, Centre for Defense Foundation Studies, National Defense University of Malaysia, Sungai Besi Camp, 57000 Kuala Lumpur, Malaysia
3. Department of Chemistry, Faculty of Science, Universiti Putra Malaysia (UPM), 43400 Serdang, Selangor, Malaysia