Achieving Color‐Tunable and Time‐Dependent Organic Long Persistent Luminescence via Phosphorescence Energy Transfer for Advanced Anti‐Counterfeiting

• Published in: Advanced functional materials 2023-01, Vol.33 (1), p.n/a
• Main Authors: Wang, Deliang, Gong, Junyi, Xiong, Yu, Wu, Hongzhuo, Zhao, Zheng, Wang, Dong, Tang, Ben Zhong
• Format: Article
• Language: English
• Subjects: advanced anti‐counterfeiting; Color; Counterfeiting; Doping; Energy transfer; Fluorescent dyes; Isomers; long persistent luminescence; Luminescence; Materials science; organic afterglow materials; Organic materials; Phosphorescence; phosphorescence energy transfer; Polyvinyl alcohol; Time dependence; ultralong room‐temperature phosphorescence
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202208895

Organic ultralong room‐temperature phosphorescence (RTP) materials have promising applications in anti‐counterfeiting. To improve the encryption level, the exploration of organic materials with tunable solid‐state long persistent luminescence is in urgent need. Herein, a series of organic ultralong RTP polymeric systems are prepared by doping versatile indolocarbazole isomers into the poly(vinyl alcohol) (PVA) matrix. Notably, the doping film 11,12‐ICz@PVA exhibits excellent RTP property with an ultralong lifetime of 2.04 s and a high phosphorescence quantum yield of 44.1%. Theoretical calculations reveal that this excellent RTP property can be attributed to the strong electrostatic attraction resulting from the synergistic double hydrogen‐bond between the isomer 11,12‐ICz and PVA matrix. More impressively, color‐tunable and time‐dependent long persistent luminescence is successfully achieved through efficient phosphorescence energy transfer between the indolocarbazole isomers with ultralong blue RTP emissions and commercially available fluorescent dyes with emission colors ranging from green to red doped into the PVA matrix. Besides, diversified encryption patterns are fabricated to demonstrate the promising applications of these water‐soluble doping PVA systems with tunable solid‐state persistent luminescence in advanced anti‐counterfeiting technology. Color‐tunable and time‐dependent organic afterglow materials are achieved via efficient phosphorescence resonance energy transfer within three‐component doping PVA systems, in which indolocarbazole isomers with ultralong blue RTP emissions act as energy donors while commercially available fluorescent dyes with emission colors ranging from green to red act as energy acceptors.