Thick-shell core-shell quantum dots are widely used due to their high stability and large Stokes shifts LED display , Solar energy and biological applications; especially red, green, blue, three primary colors, in Q LED backlight , display Etc. However, it is reported that the thick shell nucleus shell quantum dots, mainly the red CdSe / CdS core shell quantum dots, are still difficult to prepare green and narrow half-width quantum dots.
So far, a few companies and schools have devoted themselves to the preparation of thick-shell core-shell quantum dots, such as the Monaco Institute of Advanced Technology reported a green-emitting CdSe / ZnS / CdSZnS alloy core-shell quantum with a quantum yield of 100% The initial luminescence intensity of 71% can still be retained after the composite of silicone resin is obtained, but its cost is high because it is used in the preparation of alkylphosphoric acid used in the core.A well-known university in the world reported efficient green luminescent Cd1xZnxSe / ZnSe / ZnS quantum dots, Wide and no wavelength tunable results reported.A well-known professor of domestic research team reported the red light-emitting thick shell CdSe / CdS core-shell quantum dots preparation, but its preparation method is more difficult to apply to the green light-emitting core quantum dots. Therefore, the disadvantages of the existing methods largely limit the wide application of the thick core quantum dots.
The present invention for incomplete reaction of CdSe (< 530nm) 量子点, 可以有效的除去未完全反应的Cd2+ Plasma , And then can effectively control the core-shell quantum dot emission peak.Therefore, the present invention has a wider range of use and can be applied to the preparation of thick shell core-shell quantum dots with multi-wavelength ranges such as green, red, etc. Particularly suitable for thick shell green The preparation of quantum dots, as well as the incomplete growth of the quantum dot nuclei (ie, the system contains a large amount of unreacted core matrix, which can greatly affect the shell growth if not removed).
Compared with the existing preparation method, has the following advantages:
1, low cost
2, adjustable wavelength, half width and width, high quantum yield.
3, quantum dot emission peak without redshift.
4, the efficient and stable green quantum dots in the present invention are conducive to industrial mass production.
The invention provides a simple and economical method for preparing high-efficiency green luminescent core-shell quantum dots. The method is based on an organic phosphine reagent-assisted quantum dot extraction and purification process, and can be used for preparing a material with controlled wavelength, full width at half maximum, quantum yield High thick shell core quantum dots, compared with other preparation methods, this method can greatly enhance the stability of quantum dots.
