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Large-scale polymeric carbon nanotube membranes with sub-1.27-nm pores.

ABSTRACT: We report the first characterization study of commercial prototype carbon nanotube (CNT) membranes consisting of sub-1.27-nm-diameter CNTs traversing a large-area nonporous polysulfone film. The membranes show rejection of NaCl and MgSO4 at higher ionic strengths than have previously been reported in CNT membranes, and specific size selectivity for analytes with diameters below 1.24 nm. The CNTs used in the membranes were arc discharge nanotubes with inner diameters of 0.67 to 1.27 nm. Water flow through the membranes was 1000 times higher than predicted by Hagen-Poiseuille flow, in agreement with previous CNT membrane studies. Ideal gas selectivity was found to deviate significantly from that predicted by both viscous and Knudsen flow, suggesting that surface diffusion effects may begin to dominate gas selectivity at this size scale.

SUBMITTER: McGinnis RL

PROVIDER: S-EPMC5844709 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Large-scale polymeric carbon nanotube membranes with sub-1.27-nm pores.

McGinnis Robert L RL Reimund Kevin K Ren Jian J Xia Lingling L Chowdhury Maqsud R MR Sun Xuanhao X Abril Maritza M Moon Joshua D JD Merrick Melanie M MM Park Jaesung J Stevens Kevin A KA McCutcheon Jeffrey R JR Freeman Benny D BD

Science advances 20180309 3

We report the first characterization study of commercial prototype carbon nanotube (CNT) membranes consisting of sub-1.27-nm-diameter CNTs traversing a large-area nonporous polysulfone film. The membranes show rejection of NaCl and MgSO<sub>4</sub> at higher ionic strengths than have previously been reported in CNT membranes, and specific size selectivity for analytes with diameters below 1.24 nm. The CNTs used in the membranes were arc discharge nanotubes with inner diameters of 0.67 to 1.27 nm ...[more]

PMID: 29536038

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