A method for improving the stability of quantum dots in aqueous phase

Abstract

The invention discloses a method used for increasing the stability of a water phase quantum dot. According to the method, an ionic liquid and the water phase quantum dot are subjected to ligand exchange so as to obtain a modified quantum dot ionic liquid, wherein the boiling point of the obtained modified quantum dot ionic liquid is high, is usually higher than 200 DEG C, and the stability of the modified quantum dot ionic liquid is always better than that of small molecular ligands, such as mercaptoacetic acid, mercaptopropionic acid, and glutathione, used for conventional water phase quantum dot preparation. The ligand exchange of the ionic liquid with the water phase quantum dot is adopted, so that the ionic liquid is converted into a quantum dot coated by a ligand, and the stability of single quantum dot is improved; the ionic liquid is an ionic crystal, an inorganic salt crystal is also ionic crystal, the ionic liquid modified quantum dot is capable of matching growth process of inorganic salt crystal, after mixing with inorganic salt, agglomeration among quantum dot is not easily caused, and uniform dispersed solid state quantum dot with high stability is obtained; the particle size of the solid state quantum dot can be adjusted via grinding, so that solid state quantum dot of different optical properties can be obtained.

Description

technical field [0001] The invention relates to the field of lighting technology, in particular to a method for improving the stability of quantum dots in water phase. Background technique [0002] Semiconductor lighting technology is a new type of lighting technology based on high-efficiency white light emitting diodes (White Light Emitting Diode, WLED), which is recognized as one of the most promising high-tech fields in the 21st century. In terms of the domestic LED industry, the overall output value of my country's semiconductor lighting industry exceeded 500 billion yuan for the first time in 2016, and the industry scale reached 521.6 billion yuan, but most of it was concentrated in the downstream assembly process, and the production capacity of high-tech was low, and the main competitive technologies were still in the hands of Foreign patents. The nine major national key research and development plans in 2016 again mention the concept of nanometer and quantum, and the ...

AI Technical Summary

Problems solved by technology

However, the current conventional water-phase quantum dots, especially red quantum dots, have poor luminescence performance, wide half-peak width, and low quantum yield; at the same time, the preparation time is long and the stability is poor, so they cannot be directly used in high-efficiency LEDs, especially in the field of display backlighting.

[0006] However, the quantum dot crystal quality, luminous intensity, and stability obtained in the aqueous phase system are poor, and it is difficult to control the preparation of the core-shell structure, which is difficult to improve stability.

The existing application of water-phase quantum dots is mainly concentrated in the field of bioluminescent probes. At the same time, the quality of water-phase quantum dot crystals obtained by traditional preparation processes is poor, and there are relatively few research works on WLEDs, especially about wide color gamut. (>110% NTSC), high CRI (Ra>90, R9>90) show that the field of lighting is still blank

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