1. School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore
2. Energy Research Institute @ NTU (ERI@N) Nanyang Technological University 50 Nanyang Drive Singapore 637553 Singapore
3. School of Computer Science and Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore
4. Department of Electrical Engineering City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong SAR 00000 Singapore