Preparation and luminescent modulation of yellow carbon dots for electroluminescent device

Carbon dots have become the strong competitive materials for the light-emitting layer material of electroluminescent devices due to their lower toxicity and without heavy metal ions. In this experiment, bright yellow-orange fluorescent carbon dots have been synthesized by one-step solvent thermal method and the fluorescence is increased by adjusting the pH, which has excitation independent characteristics. Simultaneously, the solvent effect relating to the polarity of the solvent and the surface functional groups are investigated by the variety of emission peaks in different solvents. Based on its excellent optical properties, the electroluminescent devices were prepared using the mixture of as-prepared carbon dots and PVK as an emissive layer. The photoelectronic properties of the carbon dots-based device were measured and the luminance can reach 220 cd/m2, and the color coordinate was located at (0.30, 0.65), which provided a solid foundation for the application of carbon dots in photoelectric devices.