Synthesis of CdSe/Zns green emitting 'giant' quantum dots by silar process

Green emitting 'giant' quantum dots are highly photostable, blinking free and show unique optical properties due to the quantum confinement effect. Due to excellent optical properties this material is used in different electrical devices e.g., LEDs, photo-detectors, photo-catalyst as well as photo-voltaic. These highly efficient quantum dots have been synthesized with gradient alloy approach. Furthermore, the ZnS shell was grown around the CdSe core using Successive Ionic Layer Adsorption and Reaction (SILAR) process. By using the gradient alloy synthesis, we have prepared four different size dependent quantum dot samples to investigate the shell thickness dependent photostability under UV irradiation till 48 hours and the temperature dependent photoluminescence properties from 10°C to 90°C. We investigated that there was a small change of the UV light irradiation on the photostability after a certain thickness of the shell. The diameter of quantum dots ≥ 8.5 nm showing improvement in the photostability under continuous UV irradiation while the diameter ≤ 7.12 nm showing dramatic change in the photostability in continuous irradiation under the strong UV light (8 W/cm², 365 nm). In the case of temperature dependent stability, there were no apparent changes in PL intensities observed for the QDs ≥ 8.5 nm, on the contrary, for example, QDs with < 8.5 nm in diameter (for -'7.12 nm) show a decrease in PL intensity at higher temperatures -'90°C. These synthesized green emitting "giant" quantum dots which showing superior optical properties can be used in fabrication and highly efficient green emitters