Unlocking Multi-photoresponse in Phenothiazine Derivatives Through Photoinduced Radical and Keto-Enol Tautomerism

Achieving photochromism, photodeformation, and photoinduced room-temperature phosphorescence (RTP) simultaneously in a single type of molecule-doped film is a complex and challenging task. Here, we introduce an efficient design strategy that utilizes dicarbonyl as a bridge linking between phenothiazine (PTZ) units, thereby enabling a synergistic multi-photoresponse upon photoactivation. Our study reveals that thin films of polyvinyl alcohol (PVA) doped with five PTZ derivatives (DPTZCn: n = 1–5) show photoactivated RTP. Notably, the DPTZC1 variant in PVA film uniquely undergoes photoactivated macroscopic deformation and displays enhanced photoluminescence efficiency compared to its PTZ counterparts (DPTZCn: n = 2–5) in PVA films. Further photophysical analysis indicates that the exceptional performance of DPTZC1 stems from the combined effects of keto-enol tautomerism and matrix rigidification, which also facilitate the generation of photoinduced radicals in DPTZC1 in the PVA film. We investigate the potential bionic applications of the versatile DPTZC1, providing insights into the design of intelligent, photodriven materials based on RTP. (Figure Presented).