1. Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link Singapore 637371 Singapore
2. Institute of Materials Research and Engineering Agency for Science, Technology and Research (A*STAR) 2 Fusionopolis Way, Innovis, #08-03 Singapore 138634 Singapore
3. Division of Biological and Environmental Sciences & Engineering Water Desalination and Reuse Center King Abdullah University of Science and Technology Thuwal 23955-6900 Saudi Arabia