1. Centre for Advanced Materials and Renewable Resources, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia;
2. Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Malaysia;
3. School of Chemical Science, Universiti Sains Malaysia, Minden, Malaysia;
4. Unisza Science and Medicine Foundation Centre, Unversiti Sultan Zainal Abidin, Kampus Gong Badak, Kuala Nerus, Malaysia