One-step synthesis of color-tunable carbon dots-based organic long persistent luminescence materials

The use of carbon dots (CDs) to construct binary donor–acceptor exciplex systems has been shown to be an effective method for obtaining organic long persistent luminescence (OLPL). However, such a system currently necessitates the prior synthesis of CDs before integration with the organic matrix, thus complicating the reproducibility and large-scale production of the materials. Furthermore, attaining color-tunable long persistent luminescence (LPL) is also a major challenge for the system. Here, we report a one-step synthesis strategy for color-tunable CDs-based OLPL material (named CDs@CA). CDs donors and CA acceptors in the material can be generated in a single step during the reaction. Under ambient conditions and even in aqueous media, the LPL color of CDs@CA can be changed by the excitation wavelength, enabling color tuning from blue to green emission. This is the first time for the color tuning to be achieved in CDs-based OLPL materials. Meanwhile, the strategy is applicable to a wide range of alternative carbon sources, which makes it possible to rapidly prepare a wide range of CDs-based OLPL materials with varying LPL performance by selecting different carbon sources. This work is greatly beneficial to the development and application of CDs-based OLPL systems.