1. School of Materials Science and Innovation, Faculty of Science, Mahidol University, Nakhon Pathom 73170, Thailand
2. Thai Carbon & Graphite Co., Ltd., 15/2 Phutthamonthon Sai IV Road, Kratumban District, Samutsakorn 74130, Thailand
3. Department of Physics, Faculty of Science, Mahidol University, 272 Rama VI Road, Ratchathewi District, Bangkok 10400, Thailand
4. Rubber Technology Research Centre, Faculty of Science, Mahidol University, Nakhon Pathom 73170, Thailand
5. Research Network of NANOTEC at Mahidol University, National Nanotechnology Center, Bangkok 10400, Thailand