1 School of Materials Science and Engineering, Nanyang Technological University Singapore, N4.1, 50 Nanyang Avenue, Singapore, 639798, Singapore.
2 School of Biological Sciences, Nanyang Technological University Singapore, 60 Nanyang Drive, Singapore, 637551, Singapore.
3 Environmental Chemistry and Materials Centre, Nanyang Environment and Water Research Institute, 1 CleanTech Loop, CleanTech One, Singapore, 637141, Singapore.
4 Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore.