1. Department of Chemistry, Kookmin University, 77 Jeongneung-ro, Seongbuk-gu, Seoul 136-702, Republic of Korea
2. Applied Quantum Composites Research Center, Institute of Advanced Composite Materials, Korea Institute of Science and Technology, Joellabuk-do 565-905, Republic of Korea
3. Department of Energy Science, Sungkyunkwan University, 2066 Seobu-Ro,
Jangsan-Gu, Suwon 440-746, Republic of Korea