1. College of Materials and Chemical Engineering; China Three Gorges University; Yichang 443002 China
2. School of Physical and Mathematical Sciences; Nanyang Technological University; Singapore 637371 Singapore
3. Hubei Provincial Collaborative Innovation Center for New Energy Microgrid; China Three Gorges University; Yichang 443002 China
4. Research and Development Center for Solid State Lighting; Institute of Semiconductors; Chinese Academy of Sciences; Beijing 100083 China
5. School of Physics and Optoelectronic Engineering; Ludong University; Yantai 264025 China