Progressive advancement of ZnS-based quantum dot LED

Zn1-xCdxS1-ySey: x, y= 0-1 quantum dots (QDs) have been studied for their unique properties, which are: controllable size synthesis, tunable band gap, high quantum efficiency, narrow full width at half maximum (FWHM), high stability and easily tunable emission wavelength in the visible region. They are widely used for the synthesis of quantum dot light-emitting diodes (QLEDs) for display and lighting applications. In this review, general introduction of the development of ZnCdSSe QDs and their uses, synthesis methods of QLEDs, basic properties of ZnS, ZnSe, CdS, and CdSe QDs, the effect of exposure time and temperature on particle size and band gap, the effect of QDs size on the emission of light, basic terms for efficiency, core/shell structure-based QLEDs and doping of rare earth elements into the ZnCdSSe QDs are described.