Preparation of highly luminescent BaSO4 protected CdTe quantum dots as conversion materials for excellent color-rendering white LEDs

Abstract

The incorporation of colloidal CdTe quantum dots into an inorganic matrix, BaSO₄, through a handy and rapid co-precipitation method is demonstrated for the first time. Owing to the protection of the BaSO₄ matrix, the resulting composites show stronger luminescence, longer fluorescent lifetime, and higher photo- and thermal stability as well as being more anti-acid compared to the parental CdTe QDs. Moreover, the composites hold several advantages for industrial applications. White light-emitting diodes (WLEDs) utilizing the composites as a red color conversion layer are fabricated, and produce bright white light with high color-rendering properties including a CIE coordinate of (0.34, 0.33), an R_a of 88, and a T_c of 5112 K at 20 mA, suggesting their great potential application in a solid-state lighting system with high color-rendering properties.