We demonstrated for the first time that inkjet printing can be a low-cost, easy, fast, and scalable method for depositing ultrathin (7.5–60 nm) uniform graphene oxide (GO) nanofiltration membranes on polymeric supports for highly effective water purification. A large area (15 × 15 cm 2 ) GO nanofiltration membrane was printed successfully on a modified polyacrylonitrile (M-PAN) support. Water permeance and rejection of small organic molecules (<1 nm, charged and uncharged) of printed GO membranes can be adjusted by controlling the GO “ink” concentration and/or printing time. Compared with commercial polymeric nanofiltration membranes, printed GO membranes, after optimization, showed approximately one order of magnitude higher water permeance and much higher rejection (>95%) of small organic molecules. Printed GO membranes also showed excellent performance in removing pharmaceutical contaminants, with ∼95% rejection and <10% water permeance decline over extended-period permeation testing. We believe that inkjet printing could be an effective method for preparing ultrathin GO membranes for effective water nanofiltration purification.
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Emulsion Assembly of Graphene Oxide/Polymer Composite Membranes
Graphene oxide/polymer composite water filtration membranes were developed via coalescence of graphene oxide (GO)
stabilized Pickering emulsions around a porosity-generating polymer. Triptycene poly(ether ether sulfone)-CH2NH2:HCl polymer interacts with the GO at the water−oil interface, resulting in stable Pickering emulsions. When they are deposited and dried on polytetrafluoroethylene substrate, the emulsions fuse to form a continuous GO/polymer composite membrane. X-ray diffraction and scanning electron microscopy demonstrate that the intersheet spacing and thickness of the membranes increased with increasing polymer concentration, confirming the polymer as the spacer between the GO sheets. The water filtration capability of the composite membranes was tested by removing Rose Bengal from water, mimicking separations of weak black liquor waste. The composite membrane achieved 65% rejection and 2500 g m−2 h−1 bar−1. With high polymer and GO loading, composite membranes give superior rejection and permeance performance when compared with a GO membrane. This methodology for fabrication membranes via GO/polymer Pickering emulsions produces membranes with a homogeneous morphology and robust chemical separation strength.
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- Award ID(s):
- 2207299
- PAR ID:
- 10517316
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Applied Materials & Interfaces
- Volume:
- 15
- Issue:
- 17
- ISSN:
- 1944-8244
- Page Range / eLocation ID:
- 21384 to 21393
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsami.3c02636
