1. School of Chemical Engineering, Chonnam National University, Gwangju 61186, South Korea
2. Laser Research Center, Korea Photonics Technology Institute, Gwangju 61007, South Korea
3. Optoelectronics Convergence Research Center, Chonnam National University, Gwangju 61186, South Korea
4. Korea Institute of Ceramic Engineering and Technology, Chungmugong-dong, Jinju 52851, South Korea
5. Department of Materials Science and Engineering, Chungnam National University, Daejone 34134, South Korea