1. School of Chemistry, South China Normal University, Guangzhou 510006, P. R. China
2. Laboratory of Beam Technology and Energy Materials, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, P. R. China
3. State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, P R. China
4. Department of Electrical and Electronic Engineering, The Hong Kong Polytechnic University Hung Hom, Kowloon, Hong Kong 999077, P. R. China
5. Institut National de la Recherche Scientifique (INRS), Centre Énergie Matériaux Télécommunications, Varennes J3X 1P7, Canada