title: Fine-Tuning the Surface of Forward Osmosis Membranes via Grafting Graphene Oxide: Performance Patterns and Biofouling Propensity.
abstract: Graphene oxide (GO) nanosheets were attached to the polyamide selective layer of thin film composite (TFC) forward osmosis (FO) membranes through a poly L-Lysine (PLL) intermediary using either layer-by-layer or hybrid (H) grafting strategies. Fourier transform infrared spectroscopy, zeta potential, and thermogravimetric analysis confirmed the successful attachment of GO/PLL, the surface modification enhancing both the hydrophilicity and smoothness of the membrane's surface demonstrated by water contact angle, atomic force microscopy, and transmission electron microscopy. The biofouling resistance of the FO membranes determined using an adenosine triphosphate bioluminescence test showed a 99% reduction in surviving bacteria for GO/PLL-H modified membranes compared to pristine membrane. This antibiofouling property of the GO/PLL-H modified membrane was reflected in reduced flux decline compared to all other samples when filtering brackish water under biofouling conditions. Further, the high density and tightly bound GO nanosheets using the hybrid modification reduced the reverse solute flux compared to the pristine, which reflects improved membrane selectivity. These results illustrate that the GO/PLL-H modification is a valuable addition to improve the performance of FO TFC membranes.
authors.affiliation: †Centre for Water Management and Reuse, University of South Australia, Adelaide SA 5095, Australia.|‡Institute of Advanced Technology and New Materials, City of Scientific Research and Technological Applications, Borg Elarab, Alexandria, Egypt.
authors.forename: Hanaa M
authors.initials: HM
authors.lastname: Hegab
authors.affiliation: §Genetic Engineering and Biotechnology Research Institute, University of Sadat City (USC), Sadat City, Egypt.|∥School of Chemical Engineering, University of Adelaide, Adelaide SA 5095, Australia.
authors.forename: Ahmed
authors.initials: A
authors.lastname: ElMekawy
authors.affiliation: ⊥Mawson Institute, University of South Australia, Adelaide, SA 5095, Australia.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Barclay
authors.affiliation: ⊥Mawson Institute, University of South Australia, Adelaide, SA 5095, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Michelmore
authors.affiliation: †Centre for Water Management and Reuse, University of South Australia, Adelaide SA 5095, Australia.|#Department of Chemical and Environmental Engineering, Masdar Institute of Science and Technology, Abu Dhabi, United Arab Emirates.
authors.forename: Linda
authors.initials: L
authors.lastname: Zou
authors.affiliation: †Centre for Water Management and Reuse, University of South Australia, Adelaide SA 5095, Australia.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Saint
authors.affiliation: ⊥Mawson Institute, University of South Australia, Adelaide, SA 5095, Australia.
authors.forename: Milena
authors.initials: M
authors.lastname: Ginic-Markovic
mesh_terms: D001419:Bacteria / Q000187:drug effects; D057219:Biofouling; D006108:Graphite / Q000737:chemistry*; D008567:Membranes, Artificial; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry / Q000633:toxicity; D010087:Oxides / Q000737:chemistry; D011107:Polylysine / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013818:Thermogravimetry; D014867:Water / Q000737:chemistry
chemical_list: D008567:Membranes, Artificial; D010087:Oxides; D014867:Water; D011107:Polylysine; D006108:Graphite
keywords: antifouling; forward osmosis; grafting; graphene oxide; thin film composite membrane