Quantum-dot nanometer particle containing hydrophobic interlayer and preparation method thereof

Abstract

The invention relates to a quantum-dot nanometer particle containing a hydrophobic interlayer and a preparation method thereof. The particle is composed of a core, a hydrophobic interlayer and a shell from inside to outside; the core is a quantum-dot nanometer particle or a magnetic quantum-dot nanometer particle; the hydrophobic interlayer has a compact hydrophobic structure, and comprises an intrinsic surface ligand molecule of the quantum-dot nanometer particle or the magnetic quantum-dot nanometer particle, an ionic surfactant containing a saturated aliphatic chain and a silicon precursor reagent containing a saturated aliphatic chain; the shell is a silicon dioxide shell; and the particle size of the core is more than 3 nm and less than 10 nm, and the shell thickness is 0.6-0.7 nm. The water-soluble quantum dot with high quantum yield is prepared for the first time, and the hydrophobic interlayer is capable of effectively preventing factors going against fluorescence emission in the environment, and therefore the quantum dot or magnetic quantum-dot nanometer particle with high fluorescent quantum yield is obtained.

Description

technical field [0001] The invention relates to a quantum dot nano particle, in particular to a high fluorescence quantum yield quantum dot nano particle containing a hydrophobic interlayer and a preparation method thereof. Background technique [0002] Quantum dots (quantum dots, QDs), also known as semiconductor nanocrystals (Semiconductor nanocrystals), are composed of II-VI or III-V elements and have very superior optical properties (wide excitation spectrum, narrow emission spectrum , tunable emission spectrum, not easily photobleached) nanomaterials. Common quantum dots can be divided into: [0003] 1) Dual-element quantum dots [0004] Group II-VI: [0005] CdS,CdSe,CdTe,ZnS,ZnSe,ZnTe,MgS,MgSe,MgTe,CaS,CaSe,CaTe,SrS, [0006] SrSe,SrTe,BaS,BaSe,BaTe,HgS,HgSe [0007] III-V family: [0008] InAs, GaAs, InP [0009] 2) Alloy quantum dots: [0010] CdSeS, CdSeTe, etc. [0011] 3) Doped quantum dots: [0012] Mn doped ZnS, Mn doped CdS, etc. [0013] Magnetic q...

AI Technical Summary

Problems solved by technology

[0020] There are technical difficulties in the above method, the most important of which is that the use of the above strategy will destroy the luminous efficiency of quantum dots: in the ligand replacement method, the new ligand destroys the original surface structure and causes the reduction of the fluorescence quantum efficiency. The problem also exists in the silica cladding

Although the block polymer encapsulation method does not damage the surface of quantum dots, its loose structure is difficult to block quenching factors such as metal ions and oxygen in the environment.

The fluorescence quantum efficiency of water-soluble quantum dots prepared by the above three traditional methods will be significantly reduced.

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