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Indexed by:期刊论文

Date of Publication:2018-10-01

Journal:NANO LETTERS

Included Journals:SCIE

Volume:18

Issue:10

Page Number:6150-6156

ISSN No.:1530-6984

Key Words:Carbon nanotubes; composite membrane; biofuel; separation; pervaporation

Abstract:Synthetic membranes usually suffer from a ubiquitous trade-off between permeability and selectivity. Carbon nanotube (CNT)-based hybrid materials have shown attractive properties in high-performance membrane preparation; however, the aggregation of random CNTs in polymer remains a great challenge. Herein, the aligned and open-ended CNT/(polydimethylsiloxane) PDMS membranes are controllably fabricated to form a hamburger-like structure that possesses nanochannels (similar to 10 nm) in the intermediate layer as well as angstrom cavities in the embedded PDMS. These aligned CNT membranes surpass the filling content limitation of the nonaligned CNT/PDMS membrane (37.4 wt % versus similar to 10 wt %), leading to excellent mechanical properties and a multiplying performance increase of mass flux and selectivity for the separation of alcohols. The membranes break the permeability-selectivity trade-off with both parameters remarkably increasing (maximum 9 times) for bioalcohol separation. The established pervaporative-ultrafiltration mechanism indicates that the penetrant molecules preferentially pass through CNT internal nanochannels with increasing membrane permeability, thereby paving a way to nanoscale design of highly efficient channeled membranes for separation application.