Photochromic supramolecular photonic crystals based on host-guest interactions

A novel photo-responsive supramolecular hydrogel inverse opal material was described in this communication. The inverse opal material contains a host component beta-cyclodextrin (beta-CD) and a guest component 3-(acryloyl)amino-1,1 ',5,5 '-tetramethoxyazobenzen (MAzo). trans-MAzo has stronger association with beta-CD than cis-MAzo. Under the irradiation of blue light (475 nm), the MAzo moieties transformed to the trans-configuration, resulting in blue-shift of the structural colour. In contrast, being irradiated with red light (620 nm) regulated MAzo to the cis-configuration and dissociated the host-guest pair; subsequently, the structural colour shifted to red. Therefore, in this system, the variation of the structural colour is in correspondence with the wavelength trend of the incoming light.

Automated summary

The novel photo-responsive supramolecular hydrogel inverse opal material described in this communication can shift its structural color towards blue or red under blue or red light irradiation, respectively.