Lifetime-tunable room-temperature phosphorescence of polyaniline carbon dots in adjustable polymer matrices

Despite the excellent room-temperature phosphorescence (RTP) property of carbon dot (CD)-based RTP composites, the development of these emerging materials with finely tunable afterglow lifetimes still remains a challenge. Herein, for the first time, we report a series of pure organic RTP composite materials based on adjustable polyaniline carbon dots (PACDs) and polymer matrices (polyacrylic acid, polyacrylamide, and polyvinyl alcohol) with tunable RTP lifetimes. By using different polymer matrices and adjusting the functional groups of PACDs, the strength of hydrogen bonding between each polymer matrix and PACDs was regulated, and green RTP emissions with a tunable average lifetime ranging from 184 ms to 652 ms were also realized. In addition, taking advantage of their different persistent afterglow lifetimes, naked-eye-observable and time-resolved anti-counterfeit and data encryption patterns were prepared using these PACDs/polymer composites, demonstrating the potential application of these materials.