Preparation of cdsezns/zns/zns core/shell/shell quantum dots

Abstract

The invention provides preparation of a CdSeZnS / ZnS / ZnS core / shell / core quantum dot. The preparation comprises following steps: reacting a cadmium source and a zinc source with oleic acid and 1-octadecene to prepare a cation precursor; reacting a selenium source and a sulfur source with trioetyl phosphine to prepare an anion precursor; rapidly injecting the anion precursor into the cation precursor at a certain temperature to carry out reactions to obtain a quantum dot core; using an injection pump, controlling the shell growth temperature, the shell precursor injection amount, and injection speed, growing a first layer prepared from zinc oleate and octyl mercaptan, and growing a second layer prepared from oleylamine zinc and oleylamine sulfur to obtain the CdSeZnS / ZnS / ZnS green light core / shell / core quantum dot. The prepared quantum dot has the advantages of uniform size and morphology, low half-width, high fluorescence efficiency, and low cadmium content, is widely applied to the fields of illumination and display, is especially suitable for a full solution inverted device structure, and is capable of largely improving the device efficiency and prolonging the service life.

Description

technical field [0001] The invention relates to the field of quantum dot preparation, in particular to the preparation of green light CdSeZnS / ZnS / ZnS core / shell / shell quantum dots for an inverted light-emitting diode with high efficiency and long life. Background technique [0002] Quantum dots are semiconductor nanoparticles with a particle size between 1-20nm, and their properties are mainly determined by their composition, size, and shape. When the radius of the quantum dot is smaller than the Bohr radius, it exhibits a strong quantum confinement effect. By adjusting the particle size of quantum dots, the emission wavelength can be adjusted. By performing ligand exchange and shell growth on the surface of quantum dots, the stability and luminescent performance of the material can be improved. After the improvement of the synthesis method, quantum dot materials with luminous efficiency of 100% have been reported. Quantum dots have broad application prospects in liquid c...

AI Technical Summary

Problems solved by technology

Although the maximum external quantum efficiencies of inverted red, green, and blue quantum dot diodes reach 20.74, 22.4, and 8.38% respectively, the lifetimes of current devices are less than 300h, which cannot meet the requirements of use.

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