Component regulation and crystallization mechanism of CsPbBr3/Cs4PbBr6 perovskite composite quantum dots-embedded borosilicate glass for light emitting application

Cesium lead bromide CsPbBr3/Cs4PbBr6 perovskite composite QDs-embedded borosilicate glass (QDs@glass) have been prepared by using the conventional melting-quenching and heat-treatment technique. The effect of raw components and melting condition on the crystallization process, phase transition and crystal growth of CsPbBr3/Cs4PbBr6 QDs in the glass matrix were discussed in details. The formation of Cs4PbBr6 in glass has a significant impact on the optical properties of CsPbBr3 QDs. Excellent QDs@glass with high photoluminescence quantum yield (PLQY) of similar to 58% was achieved by optimizing the raw components and melting condition. The obtained QDs@glass shows outstanding thermal stability, photostability and water resistance stability. The PL intensity of QDs@glass remains 80% of the original one after being stored in a chamber with high-temperature and high-humidity (85 degrees C/RH 85%) for 70 h, and shows lithe decrease (2%) after being soaked into deionized water for 70 h. The white LED fabricated by using the as-synthesized green QDs@glass powder and red K2SiF6: Mn4+ phosphor on the surface of a blue LED chip displays luminous efficiency of 25 lm/W with CIE coordinates of (0.3328, 0.3442) at 100 mA and exhibits a wide color gamut (130% of the National Television System Committee standard).