Herein, a new carbon-based graphitic membrane composed of laminated graphitic nanoribbons with a nanometer-scale width and micrometer-scale length, the graphitic nanoribbon membrane, is reported. Compared to the existing graphitic membranes, such as those composed of graphene oxide and carbon nanotubes, the developed membrane exhibits several unique characteristics in pressure-driven systems. First, the short diffusion length through its interlayer and the free volume of its stacked nanoribbons result in high solvent flux regardless of solvent polarity (water: 25-250 L m-2 h-1 bar-1; toluene: ∼975 L m-2 h-1 bar-1; hexane: ∼240 L m-2 h-1 bar-1). The flux value for water is one order of magnitude higher, while that for nonpolar organic solvents is two to three orders of magnitude greater than the corresponding flux values obtained through commercially available nanofiltration membranes. Second, the membrane exhibits good separation performance, particularly with organic dye molecules (∼100%) and trivalent ions (∼60%), maintaining high solvent flux during extended filtration. Finally, the membrane exhibits high stability in various fluids, e.g., 1 M HCl solution, 1 M NaOH solution, toluene, ethanol, and water, as well as under hydraulic pressures of up to 50 bar. Electron microscopy observation and simulation results suggest that such distinctive features of the membrane are related to the entangled thin multilayers of the graphitic nanoribbons, which possibly originate from the high aspect ratio and narrow width of the nanoribbons.
Bibliographical noteFunding Information:
This research was supported by a grant funded by the Ministry of Science, ICT, and Future Planning (2015R1A2A1A05001844), the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (2015R1A6A3A04057367), and the Climate Change Research Hub of KAIST (grant no. N01150139).
© 2017 The Royal Society of Chemistry.
All Science Journal Classification (ASJC) codes
- Materials Science(all)