am5b01183_si_001.pdf (368.56 kB)
Voltage-Gated Transport of Nanoparticles across Free-Standing All-Carbon-Nanotube-Based Hollow-Fiber Membranes
journal contribution
posted on 2015-07-15, 00:00 authored by Gaoliang Wei, Xie Quan, Shuo Chen, Xinfei Fan, Hongtao Yu, Huimin ZhaoUnderstanding
the mechanism underlying controllable transmembrane
transport observed in biological membranes benefits the development
of next-generation separation membranes for a variety of important
applications. In this work, on the basis of common structural features
of cell membranes, a very simple biomimetic membrane system exhibiting
gated transmembrane performance has been constructed using all-carbon-nanotube
(CNT)-based hollow-fiber membranes. The conductive CNT membranes with
hydrophobic pore channels can be positively or negatively charged
and are consequently capable of regulating the transport of nanoparticles
across their pore channels by their “opening” or “closing”.
The switch between penetration and rejection of nanoparticles through/by
CNT membranes is of high efficiency and especially allows dynamic
control. The underlying mechanism is that CNT pore channels with different
polarities can prompt or prevent the formation of their noncovalent
interactions with charged nanoparticles, resulting in their rejection
or penetration by/through the CNT membranes. The theory about noncovalent
interactions and charged pore channels may provide new insight into
understanding the complicated ionically and bimolecularly gated transport
across cell membranes and can contribute to many other important applications
beyond the water purification and resource recovery demonstrated in
this study.