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.