1. Faculty of Engineering; Multimedia University; Cyberjaya 63100 Selangor Malaysia
2. Nanotechnology and Catalysis Research Centre; University of Malaya; 50603 Kuala Lumpur Malaysia
3. Department of Chemistry; University Putra Malaysia; Serdang 43400 Malaysia
4. Lee Kong Chian Faculty of Engineering and Science; Universiti Tunku Abdul Rahman; Bandar Sungai Long 43000 Cheras Selangor Darul Ehsan Malaysia