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A Photoresponsive Smart Covalent Organic Framework.

ABSTRACT: Ordered ?-columnar structures found in covalent organic frameworks (COFs) render them attractive as smart materials. However, external-stimuli-responsive COFs have not been explored. Here we report the design and synthesis of a photoresponsive COF with anthracene units as the photoresponsive ?-building blocks. The COF is switchable upon photoirradiation to yield a concavo-convex polygon skeleton through the interlayer [4?+4?] cycloaddition of anthracene units stacked in the ?-columns. This cycloaddition reaction is thermally reversible; heating resets the anthracene layers and regenerates the COF. These external-stimuli-induced structural transformations are accompanied by profound changes in properties, including gas adsorption, ?-electronic function, and luminescence. The results suggest that COFs are useful for designing smart porous materials with properties that are controllable by external stimuli.

SUBMITTER: Huang N

PROVIDER: S-EPMC4531826 | biostudies-other | 2015 Jul

REPOSITORIES: biostudies-other

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A Photoresponsive Smart Covalent Organic Framework.

Huang Ning N Ding Xuesong X Kim Jangbae J Ihee Hyotcherl H Jiang Donglin D

Angewandte Chemie (International ed. in English) 20150610 30

Ordered π-columnar structures found in covalent organic frameworks (COFs) render them attractive as smart materials. However, external-stimuli-responsive COFs have not been explored. Here we report the design and synthesis of a photoresponsive COF with anthracene units as the photoresponsive π-building blocks. The COF is switchable upon photoirradiation to yield a concavo-convex polygon skeleton through the interlayer [4π+4π] cycloaddition of anthracene units stacked in the π-columns. This cyclo ...[more]

PMID: 26095503

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