Thesis
Antifouling properties of graphene oxide and molybdenum disulfide
Washington State University
Master of Science (MS), Washington State University
2017
Handle:
https://hdl.handle.net/2376/102070
Abstract
Fouling remains one of the biggest challenges in membrane technology as fouling seriously hampers the performance of any membrane. There is, therefore, a critical need to develop antifouling membranes. Nanomaterials such as graphene oxide (GO) and molybdenum disulfide (MoS2) can also be beneficial to membrane applications as these materials have shown antibacterial properties. These materials can also be modified with a conductive polymer support such as polypyrrole for electrochemical filtration. The first objective of the study is to assess the antifouling properties of GO and MoS2 by observing the deposition kinetics of bacteria and natural organic matter (NOM) using an electrochemical quartz crystal microbalance with dissipation monitoring (EQCM-D). Results indicate that both the materials perform well as antifouling surfaces than bare polymer surfaces as foulants attaches 15 to 80% slowly on material surfaces than bare polymer poly-L-lysine (PLL) surfaces depending on solution chemistry. Results also show that overall MoS2 shows better antifouling properties over GO in most of the cases. However, presence of divalent cations (Ca2+, Mg2+) reduces the antifouling properties of both MoS2 and GO due to salt bridging effect and reduced energy barrier. Another objective of the study is to investigate whether changing the surface charge of these materials by applying external voltage can delay the attachment of the foulants on material surfaces. Bovine serum albumin (BSA) and sodium alginate (SA) were used as model foulants and polypyrrole (PPy) was used as bare polymer surface for this study. As polypyrrole (PPy) is a conducting polymer, it was used to make the GO and MoS2 surfaces conductive for voltage application. Results of this study show that it is possible to delay the attachment of the foulants on GO-PPy and MoS2-PPy surfaces upon the application of -0.5 VAg/AgCl and both the GO-PPy and MoS2-PPy surfaces perform better than bare PPy surfaces under all conditions. Results from this study are expected to be used for the development of the next-generation antifouling membranes and coatings.
Metrics
Details
- Title
- Antifouling properties of graphene oxide and molybdenum disulfide
- Creators
- Iftaykhairul Alam
- Contributors
- Indranil Chowdhury (Chair)Richard J. Watts (Committee Member)Yuehe Lin (Committee Member) - Washington State University, Mechanical and Materials Engineering, School of
- Awarding Institution
- Washington State University
- Academic Unit
- Civil and Environmental Engineering, Department of
- Theses and Dissertations
- Master of Science (MS), Washington State University
- Publisher
- Washington State University; [Pullman, Washington] :
- Identifiers
- 99900525145701842
- Language
- English
- Resource Type
- Thesis