1. School of Materials Science and EngineeringGwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Buk-gu Gwangju 500-712 South Korea
2. Fire Protection LaboratoryChemistry DivisionInstitution National Institute for Standards, 136 Giza 12211 Egypt
3. Department of Nanobio Materials and Electronics (WCU)Gwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Buk-gu Gwangju 500-712 South Korea