Colourful organic afterglow materials with super-wide color gamut and scaled processability from cellulose

Multi-colour afterglow materials have attracted widespread attention recently, because they not only can eliminate the interference of scattered light and background fluorescence, but also store the richer information. In this work, the phosphorescence emission of cellulose-based nitrogen-doped carbon dots (CDs) was transferred to the rhodamine derivatives via an efficient radiative energy transfer process, because of the strong electrostatic attraction interactions between the positive charged CDs and the negative charged rhodamine derivatives. As a result, multi-color afterglow luminescence with tunable emission and wide color gamut was realized from blue-green to green, yellow, orange and red. With the contribution of the excellent processability of polymer materials, multi-color afterglow films, coatings, fibers and patterns were readily obtained, indicating a practical application in advanced anti-counterfeiting and multiple-mode information encryption. Such a facile, universal and efficient strategy to construct multi-colour afterglow materials inspires us to understand the luminescence process and design novel afterglow materials. Multi-colour afterglow luminescence with tunable emission and wide color gamut was realized via an efficient energy transfer. • Phosphorescent nitrogen-doped carbon dots were fabricated from cellulose. • Multi-colour afterglow luminescence with tunable emission and wide color gamut was realized. • An efficient radiative energy transfer process was demonstrated.