Expanding the Color Range of Photoresponsive Multicolor Luminescent System Through Host–Guest Interaction

Photoresponsive multicolor luminescent systems offer interesting functions, which have led to applications in anticounterfeiting and biological imaging. However, expanding the color range of these materials remains a challenging task. Herein, a carbazole-modified dithienylethene derivative (<b>DTE-CZ</b>) that exhibits modulated fluorescence color changes through the photocyclization reaction and photolysis reaction is synthesized. <b>DTE-CZ</b> emits orange fluorescence, and it can release a fluorophore which emits blue fluorescence by the photolysis reaction, resulting in the color change. Upon complexation of <b>DTE-CZ</b> with cucurbit[10]uril (CB[10]), the fluorescence wavelength will have a blue shift and the photolysis reaction will be inhibited. Benefiting from the influence of CB[10] and the photolysis reaction of free guests, the color range of the photoresponsive system which is composed of free guests and host-guest complexes is further extended. White light emission along with a color shift from yellow-green to blue was achieved by adjusting the ratio of free guests to host-guest complexes. Finally, the photoresponsive multicolor systems are utilized to construct a photostimulated PVA film and an information encryption system. This work provides an alternative strategy for the preparing of photoresponsive multicolor luminescent system and modulation of its color range.