High-Power Actuation from Molecular Photoswitches in Enantiomerically Paired Soft Springs (original) (raw)
2017, Angewandte Chemie International Edition
Motion in plants often relies on dynamic helical systems as seen in coiling tendrils,spasmoneme springs,and the opening of chiral seedpods.D eveloping nanotechnology that would allow molecular-level phenomena to drive such movements in artificial systems remains as cientific challenge. Herein, we describe asoft device that uses nanoscale information to mimic seedpod opening. The system exploits af undamental mechanism of stimuli-responsive deformation in plants, namely that inflexible elements with specific orientations are integrated into as timuli-responsive matrix. The device is operated by isomerization of al ight-responsive molecular switch that drives the twisting of strips of liquid-crystal elastomers.T he strips twist in opposite directions and work against eacho ther until the pod pops open from stress.T his mechanism allows the photoisomerization of molecular switches to stimulate rapid shape changes at the macroscale and thus to maximizea ctuation power.
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