Studies On The Key Technology Of Pbse Quantum Dot Doped Glasses With High Concentration By A Melting Method

Semiconductor nanocrystal is a quasi-zero-dimensional system. They hasattracted wide spread attention due to its applications in electronic andoptical communications as a result of quantum confinement effect, surfaceeffect and macroscopic quantum tunneling effect. Particularly, narrowbandgap IV-VI materials, such as PbSe, have attracted much considerationin the word. In recent years, devices for the wavelength of1.3-1.55um inoptical communication have been widespread concerned. One simple wayto realize1.3μm laser emissions is to use semiconductor quantumdot-doped glasses, which can be synthesized by using a melting method.PbSe QDs with diameter in the range of4.5-9nm have strong PL peakswith the typical FWHM of100-200nm and potential application value inoptical fiber communication. Therefore, it is necessary to study thesynthesize of PbSe quantum dots in glass matrix. In this dissertation, the sodium-aluminum-borosilicate glasses(SiO_<sup>2-B₂O₃-Na₂O-Al₂O₃-ZnO-AlF₃) containing PbSe quantum dots （QDs）with high concentrations are synthesized by using a high-temperaturemelting method. Effect of thermal treatment condition, host glassescomposition and Pb²⁺and Se^2-precursor on concentration and size of PbSeQDs are investigated by XRD, TEM, PL spectra and IR absorption spectrua.Obtained results are described as follows.1. The QDs synthesized in the glass are with a uniformdistribution,⁶.5-nm diameter, high concentration, enhancedPL intensity peaking at1790nm and widened FWHM of296nm, upon the condition of the mass ratio （ratio of ZnO to totalbatching） of9.4%.2. Different precursors of synthesized PbSe QDs （i.g., PbO, ZnSeand PbSe powders） have great effect on the PbSe QDconcentration formed in the glass. The PbSe powder as aprecursor to form PbSe QD by a reaction of Pb²⁺and Se^2-caneasily synthesize high concentrated PbSe QDs.3. the Se oxidized in the glass can be reduced by adding thecarbon powder appropriately. There is evidence to show that itis impossible to form high concentrated PbSe QDs when thecarbon content in the glass is more than2%, while that can beeasily achieved if the carbon powder content in the glass batching is0.5%.4. Compared with conventional heat-treatment method, theheat-reatment method presented in this dissertation can beeasily synthesize high concentraiotnal PbSe QDs in thesodium-aluminum-borosilicate glass.