Expanding the Color\nRange of Photoresponsive Multicolor\nLuminescent System Through Host–Guest Interaction

Photoresponsive multicolor luminescent\nsystems offer\ninteresting\nfunctions, which have led to applications in anticounterfeiting and\nbiological imaging. However, expanding the color range of these materials\nremains a challenging task. Herein, a carbazole-modified dithienylethene\nderivative (<b>DTE-CZ</b>) that exhibits modulated fluorescence\ncolor changes through the photocyclization reaction and photolysis\nreaction is synthesized. <b>DTE-CZ</b> emits orange fluorescence,\nand it can release a fluorophore which emits blue fluorescence by\nthe photolysis reaction, resulting in the color change. Upon complexation\nof <b>DTE-CZ</b> with cucurbit[10]uril (CB[10]), the fluorescence\nwavelength will have a blue shift and the photolysis reaction will\nbe inhibited. Benefiting from the influence of CB[10] and the photolysis\nreaction of free guests, the color range of the photoresponsive system\nwhich is composed of free guests and host–guest complexes is\nfurther extended. White light emission along with a color shift from\nyellow–green to blue was achieved by adjusting the ratio of\nfree guests to host–guest complexes. Finally, the photoresponsive\nmulticolor systems are utilized to construct a photostimulated PVA\nfilm and an information encryption system. This work provides an alternative\nstrategy for the preparing of photoresponsive multicolor luminescent\nsystem and modulation of its color range.