One-step hot injection synthesis of gradient alloy CdxZn1-xSySe1-y quantum dots with large-span self-regulating ability

Abstract

CdSe-derived quantum dots (QDs) materials are highly luminescent and have been promisingly implementing a wide range of applications. However, CdSe-derived QDs with controllable emission wavelength and composition always require a highly complicated synthetic process, which badly hinders its mass production. Here, we present a simple one-step hot injection method to synthesize the versatile CdxZn1-xSySe1-y (x = 0.12, 0.17, 0.23, 0.33, y = 0, 0.64, 1) QDs with controllable composition and large-span emission wavelengths. Only by varying the molar ratios of Cd to Zn and Se to S, the emission wavelength span of the as-obtained gradient alloyed CdxZn1-xSySe1-y QDs is widely closed to 200 nm (445–643 nm), and the narrow full width at half-maximum surprisingly emerges down to 14 nm, evidently revealing that excellent self-regulating ability and superior monochromaticity. Using these different coloured QDs, we fabricate the typical red, yellow and blue light emitting diode (LED) lamps integrated with the ultraviolet chip (365 nm), showing steady and bright emission. The above results afford an efficient method to control the optical properties of QDs and ensure their processibility for further purposes in variable optoelectronics.