Phosphine-free synthesis and optical stabilities of composition-tuneable monodisperse ternary PbSe1−xSx alloyed nanocrystals via cation exchange

摘要: Compared to binary PbSe or PbS nanocrystals (NCs), ternary PbSe1−xSx alloyed NCs have unique electronic and optical properties such as high quantum efficiency, narrow band edge, fast response time, are widely used in infrared optoelectronic devices. In this work, high-quality composition-tunable monodisperse were synthesized by employing cation exchange from host CdSe1−xSx NCs, which pre-fabricated using cadmium oxide, myristic acid 1-octadecene (ODE) solutions of selenium/sulphur powders (Se/S-ODE), excluding toxic phosphine-containing solvents. The nature was confirmed powder X-ray diffraction (XRD). XRD patterns field emission transmission electron microscopy (FETEM) images demonstrated that the average diameters resulting not more than 5 nm, ultraviolet-visible-near (UV-vis-NIR) absorption spectra indicated NC size, hence gap, bared a linear relationship with first peak position. temporal evolution revealed air-stable due hybrid surface passivation Cl− Cd2+. fluorescence results slight stoichiometric deviations occurred but never exceeded 15% expected composition, based on amount introduced hosts.