Preparation and performance study of dye-based carbon quantum dots

The preparation of Full-color carbon dots is well established, but the explanation of its mechanism is not only highly controversial, but partly even contradictory to the project. Therefore, to investigate the red-shift mechanism of Full-color carbon dots, citric acid and Nile blue with complex composition structure were selected as raw materials, and B-,G-,Y- and R-CQDs were prepared by changing the reaction solvent with quantum yields of 49.7 %,28.2 %,72.3 %,30.3 % and average particle sizes of mainly 2.7–3.2 nm, respectively. TEM and XPS tests show that the emission wavelength redshift is mainly attributed to the reduction of the energy band gap due to the sp2 conjugate size and the increase of graphitic nitrogen content. To examine the optical properties of dye-based F-CQDs, F-CQDs/PVA polymer films and LEDs were prepared, both of which showed unique optical properties.