Method for fast preparing soluble near infrared CdTe quantum dots covered with mercaptan in aqueous phase

Abstract

A method for fast preparing soluble near infrared CdTe quantum dots covered with mercaptan in aqueous phase relates to the preparation field of quantum dot. The method comprises the following steps: (a) adding NaBH4 or KBH4 and Te powder, adding deionized water to react at the room temperature under magnetic stirring and prepare NaHTe or KHTe solution; (b) preparing cadmium salt or cadmium oxide, cadmium hydroxide and cadmium sulfhydryl compound solution; (c) adding the solution obtained in the step (b) in a three-necked bottle, protecting with argon, stirring; (d) adding fresh and oxygen-free NaHTe or KHTe solution prepared in the step (a) in the three-necked bottle of the step (c); and (e) heating and refluxing to react and obtain the near infrared CdTe quantum dots. The method of the invention has simple operations, mild conditions and low cost and toxicity. The synthetized mercaptan modified CdTe quantum dots have good water-solubility and stability; and the fluorescence quantum yield is high and the emission spectrum can be adjusted in the near infrared region.

Description

【Technical field】:

[0001] The invention relates to the field of preparation of quantum dots, in particular to a method for water-soluble CdTe quantum dots. 【Background technique】:

[0002] Quantum dots are semiconductor nanocrystals or microcrystals, composed of II-VI, III-V or IV-VI period elements, spherical substances with a diameter of 1-12 nanometers. At present, more studies are made on type II-VI quantum dots such as CdS, CdSe, CdTe, and ZnS. These nanoparticles exhibit different properties from macroscopic substances, including high quantum emission yields, size-tunable emission spectra, and narrow spectral bands. In addition, controlling the size can tune the position of the emission spectrum. The unique properties of quantum dots are based on their own quantum effects. When the particle size reaches the nanometer level, the size effect, quantum confinement effect, macroscopic quantum tunneling effect and surface effect are caused by the size confinement, thus der...