Correlating Interlayer Spacing and Separation Capability of Graphene Oxide Membranes in Organic Solvents
| Autor: | Jeffrey J. Urban, Sunxiang Zheng, Baoxia Mi, Monong Wang, Qingsong Tu |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Oxide General Physics and Astronomy 02 engineering and technology organic solvent nanofiltration 010402 general chemistry 01 natural sciences law.invention solubility distance swelling chemistry.chemical_compound law medicine General Materials Science Nanoscience & Nanotechnology Solubility membrane Graphene General Engineering 021001 nanoscience & nanotechnology 0104 chemical sciences Hexane Solvent Hildebrand solubility parameter interlayer spacing Membrane chemistry Chemical engineering graphene oxide Swelling medicine.symptom 0210 nano-technology |
| Zdroj: | ACS nano, vol 14, iss 5 |
| ISSN: | 1936-086X 1936-0851 |
| DOI: | 10.1021/acsnano.0c01550 |
| Popis: | Membranes synthesized by stacking two-dimensional graphene oxide (GO) hold great promise for applications in organic solvent nanofiltration. However, the performance of a layer-stacked GO membrane in organic solvent nanofiltration can be significantly affected by its swelling and interlayer spacing, which have not been systematically characterized. In this study, the interlayer spacing of the layer-stacked GO membrane in different organic solvents was experimentally characterized by liquid-phase ellipsometry. To understand the swelling mechanism, the solubility parameters of GO were experimentally determined and used to mathematically predict the Hansen solubility distance between GO and solvents, which is found to be a good predictor for GO swelling and interlayer spacing. Solvents with a small solubility distance (e.g., dimethylformamide, N-methyl-2-pyrrolidone) tend to cause significant GO swelling, resulting in an interlayer spacing of up to 2.7 nm. Solvents with a solubility distance larger than 9.5 (e.g., ethanol, acetone, hexane, and toluene) only cause minor swelling and are thus able to maintain an interlayer spacing of around 1 nm. Correspondingly, GO membranes in solvents with a large solubility distance exhibit good separation performance, for example, rejection of more than 90% of the small organic dye molecules (e.g., rhodamine B and methylene blue) in ethanol and acetone. Additionally, solvents with a large solubility distance result in a high slip velocity in GO channels and thus high solvent flux through the GO membrane. In summary, the GO membrane performs better in solvents that are unlike GO, i.e., solvents with large solubility distance. |
| Databáze: | OpenAIRE |
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