Stable CsPbX₃@SiO₂ Perovskite Quantum Dots for White-Light Emitting Diodes

Abstract

In this article, we reported the synthesis method of stable CsPbX 3 @SiO 2 quantum dots using cesium acetate instead of cesium carbonate. The results showed that CsPbX 3 @SiO 2 presents good crystallinity and excellent luminescence properties. The coating layer of SiO 2 on the CsPbX 3 quantum dots surface blocks the air and water contact and suppresses anion exchange between the quantum dots, which dramatically enhances the stability. White light-emitting diode devices are manufactured by integrating the green CsPbBr 3 @SiO 2 quantum dots and red CsPbBr 1 I 2 @SiO 2 quantum dots on the blue GaN chips. The devices show stable white light emission with Commission Internationale de L'Eclairage color coordinates (0.3511, 0.3437), and the white light intensity keeps unchanged after continuously working for 16 hours. The results indicate that CsPbX 3 @SiO 2 quantum dots can be an ideal down-conversion fluorescent material for white light-emitting diode devices.