1. School of Semiconductor and Chemical Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 561-756, Republic of Korea
2. Department of Energy Storage and Conversion Engineering, Chonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 561-756, Republic of Korea
3. Korea Institute
of Science and Technology, Jeonbuk 565-905, Republic of Korea