1. Pillar of Engineering Product and Development Singapore University of Technology and Design 8 Somapah Road Singapore 487372 Singapore
2. Science, Mathematics and Technology Singapore University of Technology and Design Somapah Road Singapore 487372 Singapore
3. College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges University Yichang 443002 P. R. China
4. Key Laboratory of Material Physics Ministry of Education School of Physics and Microelectronics Zhengzhou University Zhengzhou 450052 China