Light‐Switchable Single‐Walled Carbon Nanotubes Based on Host–Guest Chemistry

Abstract

A new type of light-switchable "smart" single-walled carbon nanotube (SWNTs) is developed by the reversible host-guest interaction between azobenzene-terminal PEO (AzoPEO) and pyrene-labeled host attached on the sidewalls of nanotubes via ππ stacking. The SWNTs hybrids not only are well dispersed in pure water, but also exhibit switchable dispersion/aggregation states upon the alternate irradiation of UV and visible light. Moreover, the SWNTs hybrids dispersion is preliminarily used as coating fl uid to form transparent conductive fi lms. The dispersant AzoPEO is removed by the contamination-free UV treatment, decreasing the resistance of the fi lms. This kind of light-switchable SWNTs hybrids, possessing a ''green'' trigger and intact structure of the nanotube, may fi nd potential applications in sensor of biomedicines, device fabrication, etc. Additionally, such a reversible hostguest interaction system may open up the possibility to control the dispersion state of SWNTs by other common polymers. Scheme 1 . The synthesis strategies for a) azobenzene-containing PEO (AzoPEO), and b) pyrene-labelled β -cyclodextrin (p-CD).

Folate-Chitosan Nanoparticles Loaded with Ursolic Acid Confer Anti-Breast Cancer Activities in vitro and in vivo

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Applications of Photoinduced Phenomena in Supramolecularly Arranged Phthalocyanine Derivatives: A Perspective

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