Free-standing bilayered nanoparticle superlattice nanosheets with asymmetric ionic transport behaviors

Siyuan Rao, Kae Jye Si, Lim Wei Yap, Yan Xiang, Wenlong Cheng

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30 Citations (Scopus)


Natural cell membranes can directionally and selectively regulate the ion transport, which is critical for the functioning of living cells. Here, we report on
the fabrication of an artificial membrane based on an asymmetric nanoparticle superlattice bilayered nanosheet, which exhibits similar ion transport
characteristics. The superlattice nanosheets were fabricated via a drying-mediated self-assembly of polystyrene-capped gold nanoparticles at the
liquidair interface. By adopting a layer-by-layer assembly process, an asymmetric nanomembrane could be obtained consisting of two nanosheets with
different nanoparticle size. The resulting nanomembranes exhibit an asymmetric ion transport behavior, and diode-like currentvoltage curves were
observed. The asymmetric ion transport is attributed to the cone-like anochannels formed within the membranes, upon which a simulation map was
established to illustrate the relationship between the channel structure and the ionic selectivity, in consistency with our experimental results. Our superlattice nanosheet-based design presents a promising strategy for the fabrication of next-generation smart nanomembranes for rationally and selectively regulating the ion transport even at a large ion flux, with potential applications in a wide range of fields, including biosensor devices, energy conversion, biophotonics, and bioelectronics.
Original languageEnglish
Pages (from-to)11218 - 11224
Number of pages7
JournalACS Nano
Issue number11
Publication statusPublished - 2015

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