Synthesis method of ZnS/CdZnS/ZnS blue light quantum dot

Abstract

The invention provides a synthesis method of a ZnS / CdZnS / ZnS blue light quantum dot. Firstly, an oil-phase ZnS quantum dot is synthesized by utilizing a zinc source precursor and an S source precursorthrough a high-temperature thermal injection method; then, a ZnS quantum dot nucleus is obtained through purification; next, the ZnS quantum dot nucleus is coated with a CdZnS luminous shell layer and a ZnS inorganic modification layer through an epitaxial growth method; finally, the ZnS / CdZnS / ZnS blue light quantum dot is obtained through purification. According to the synthesis method of the ZnS / CdZnS / ZnS blue light quantum dot, materials with different bands are prepared through changing the thickness of different CdZnS layers, and ideal quantum yield is obtained through regulating the thickness of the luminous layer; the thickness of the middle luminous layer is selected to be synthesized under 300 DEG C, so that the crystal lattice fitness between the ZnS nucleus and the CdZnS luminous layer can be relieved; a CdZnS coherence strain layer can be crystallized well; the fluorescent quantum yield of the quantum dot is obviously improved along with the coating of the ZnS shell layer;meanwhile, flicker can be inhibited, and the quantum dot fluorescent yield is high.

Description

technical field [0001] The invention relates to a synthesis method of ZnS / CdZnS / ZnS blue light quantum dots, specifically belonging to the technical field of luminescent materials. Background technique [0002] Colloidal semiconductor nanocrystals have narrow luminescence spectra and high photoluminescence quantum yields, and have attracted extensive attention for applications in displays, lasers, and solar cells. However, many hole and electron defect states are formed on the surface of quantum dots, which affect the luminescent properties of quantum dots. There are two main ways to passivate the surface state of quantum dots and increase the luminous efficiency and photochemical stability of quantum dots: one is to modify the surface of quantum dots with organic ligands; the other is to coat the surface of quantum dots with an inorganic shell. Generally, the shell material can act as a passivation layer to reduce the dangling bonds on the surface, while a thick inorganic ...

AI Technical Summary

Problems solved by technology

[0003] At present, the existing researches all involve CdSe red light and green light quantum dots or quantum dot light-emitting diodes based on CdSe red light or green light. Due to the limitation of energy level structure, blue light quantum dots cannot be synthesized by CdSe. The present invention is a A synthetic method for preparing approximately spherical ZnS / CdZnS / ZnS blue light quantum dots based on an epitaxial growth method. The synthesis method of the present invention can overcome the shortcomings of blue light quantum dots such as low yield and poor photostability, and further satisfy people's demand for blue light quantum dots and its application needs