Preparation And Charaterization Of Indium Phosphide Multilayer Core Shell Quantum Dots And Their Incorperating Into Silica Glass

Semiconductor quantum dots(QDs)are used in the fields of photoelectric display devices and fluorescence imaging due to their narrow emission spectrum,tunable emission color and high quantum yield.At present,the research on cadmium selenide(Cd Se)QDs is the most mature,but the toxicity of cadmium limits its application.Indium phosphide(InP)QDs have become alternative candidates for Cd Se QDs due to their low toxicity.However,the synthesis of InP QDs is relatively difficult.Therefore,it is necessary to form a shell on its surface for surface passivation to improve its luminescence efficiency and stability.Designing suitable core-shell structures is one of the main research directions for synthesizing InP QDs.In addition,in order to better apply InP QDs in the field of optoelectronic displays,it is necessary to embed InP QDs into suitable solid substrates to further improve their luminescence stability.The main research content and achievements of this paper are as follows:1)A multi-layer core-shell structure of InP/zinc selenide(ZnSe)/zinc selenide sulfide(ZnSeS)/zinc sulfide(ZnS)was designed to reduce lattice mismatch and internal stress between the core and each shell layer.InP nuclei were prepared using indium chloride and tri(dimethylamino)phosphine.InP multilayer core-shell QDs were synthesized in one pot with different compositions.The alloy shell of ZnSeS with composition transition was introduced between the inner shell of ZnSe and the outer shell of ZnSe.InP core-shell QDs with a half wave width of 56 nm and a luminescence efficiency of up to 70 % was obtained.2)By mixing metal ion solutions with QDs with different shell structures,the fluorescence characteristics of QDs with different shell structures were investigated,and the reasonable and effective multi-layer core-shell structure of QDs designed in this paper was successfully verified.3)Using various InP core-shell QDs with different surface ligands,the surface of QDs was ligand exchanged with 3-aminopropyl trimethoxysilane,and the effect of ligand exchange on the fluorescence properties of QDs was investigated.The silica gel glass containing InP core-shell QDs was prepared.The QDs in the gel glass still maintain their original fluorescence characteristics,and the stability has been improved.