Preparation And Luminescent Properties Of Cadmium Sulfur Selenide QDs Glass Ceramic

At present, phosphor was widely used in white Light Emitting Diode（LED）commodity on the market to convert electrical energy to visible light, and epoxy resinwas used for encapsulation. But there existed some disadvantages such as aging anddiscoloration of phosphor, decline of brightness, poor heat conduction of epoxy resinand so on in the practical application, which influenced the lifetime of white LED.Quantum dots (QDs) as one kind of the newest fluorescent material, the greatestadvantage was the tunableness of color. For any QDs material, it could emit differentcolors according to different size of quantum dots. Due to the flexibility of the glasssubstrate network, easy preparation and compatibility with fiber glass, so glass was anideal matrix material for semiconductor quantum dots.Borosilicate glass was used as matrix in this paper, the melting process ofCadmium Sulfur Selenide quantum dots glass ceramic was studied, namely theinfluence of the pretreatment of the sulfur cadmium selenide, melting temperature,feeding temperature on Cadmium Sulfur Selenide quantum dot glass ceramicpreparation. And on this basis, the influence of heat treatment system for the growthand distribution of quantum dots was discussed and the relationship between the sizeof Cadmium Sulfur Selenide quantum dots the luminescence properties was studied.Cadmium Sulfur Selenide quantum dots glass ceramic melting process was studiedthrough XRF, XRD, UV-vis spectrophotometer, the influence of the heat treatmentsystem on the growth and distribution of Cadmium Sulfur Selenide quantum dots wasexplored through DTA, TEM, XRD, the relationship between the size of CadmiumSulfur Selenide quantum dots the luminescence properties was studied through theabsorption spectrum, excitation spectra emission spectra and fluorescent lifetime. Theconclusion was summarized as follows:1. The fixing effect of CdS and Se and the growth of CdSe nanometer crystalwere the best when the ratio of Se/CdS is1:3, A3pretreatment, namely blending ZnO,CdS, Se uniformly first, then calcinating for2h at350℃, finally mixing with glassmatrix and melting at1250℃.melting temperature at1250℃, feeding temperature at900℃or1000℃. The color scope of the glass from yellow to red could be gainedthrough mixing different melting processes. 2. After heat treatment, no crystalline phase was observed through XRD test.TEM test observed that the size of quantum dots grew and the distribution extendedas the increment of heat treatment temperature and time, but the types of accuratequantum dots in the glass couldn’t be determined.3. There existed spectrum redshift trend overall in the excitation spectrum andemission spectrum as the increment of heat treatment temperature and time, whichshowed the average size of quantum dots increased as the increment of heat treatmenttemperature and time, consistent with TEM test results.4. Effective fluorescent lifetime increased firstly then decreased as the incrementof heat treatment temperature. Effective fluorescent lifetime was not obvious as theincrement of heat treatment time, but compared with blank sample, fluorescentlifetime increased obviously.