1. School of Chemical and Biomedical Engineering Nanyang Technological 62 Nanyang Drive Singapore 637459 Singapore
2. Cambridge Centre for Advanced Research and Education in Singapore Ltd. CREATE Tower Singapore 138602 Singapore
3. Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130012 P. R. China
4. Hubei Engineering Technology Research Center of Environmental Purification Materials Institute of Materials Research and Engineering Hubei University of Education Wuhan 430205 P. R. China
5. Department of Chemical Engineering and Biotechnology University of Cambridge Cambridge CB2 3RA UK