Regulating isolated-molecular and aggregated state phosphorescence for multi-color afterglow by photo-activation.

Abstract

Ultralong organic phosphorescence (UOP) materials have attracted considerable attention in recent years. Herein, a new type of flexible films was fabricated by doping amphipathic pyrene tetra sulfonic acid sodium salts into amorphous poly(vinyl alcohol) matrix, which enabled the realization of color-tunable UOP spanning from orange-red to green after excitation light switched off. Interestingly, we demonstrated precise control of the proportion of isolated-molecular and aggregated state phosphorescence for colorful afterglow using photo-activation. A 2.19-fold increase in the dynamic phosphorescence lifetime of isolated molecules was observedfrom 752.94 to 1650.46 ms following an 8-minute irradiation under ambient conditions. This flexible and processable film exhibited versatile applications in multi-color afterglow displays, ultraviolet detection, multilevel information encryption, etc. Our study not only provides a strategy for the rational regulation of UOP colors but also expands the application potential of color-tunable UOP materials. This article is protected by copyright. All rights reserved.