Triarylboron-Doped Polymer Matrix Ultralong Room-Temperature Phosphorescent Materials for Advanced Multidimensional Information Encryption

Constructing polymer-based ultralong organic room-temperature phosphorescence (UORTP) materials that exhibit time-dependent phosphorescent color variation holds profound significance. Triarylboranes, as a typical class of fluorophores, are widely used in the fabrication of various functional organic luminescent materials, and achieving UORTP materials from triarylboranes has become an important studied topic. In this study, a polymer-based UORTP material is fabricated by means of doping organic phosphor (NBC) composed of boronic acid-modified triarylborane unit into a poly(vinyl alcohol) (PVA) matrix, which is attributed to the hydrogen bonding between NBC and PVA, effectively suppressing the nonradiative decay. The experimental results show that the afterglow color of NBC@PVA film gradually changed from orange to green after irradiation with 365 nm UV light, thereby successfully realizing a polymer-doped phosphorescent material characterized by an ultralong lifetime and color variability. By employing two fluorescent dyes, namely, Rhodamine B and Fluorescein, as energy acceptors, we successfully engineered color-tunable UORTP emission. Furthermore, the excellent applicability of these materials in information encryption and anticounterfeiting has also been demonstrated.