1. School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
2. Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province, College of Physics Science and Technology, Hebei University, Baoding 071002, P. R. China
3. Institute of Sustainability for Chemicals, Energy and Environment, A*STAR, Singapore 627833, Singapore
4. State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
5. Institute of Materials Research and Engineering, A*STAR, Singapore 138634, Singapore