In situ precipitation of high efficiency and high thermostability CsPbBr3 quantum dots in borosilicate glass for wide color gamut display

Abstract

In situ precipitation of CsPbBr3 quantum dots (QDs) in glass is considered as one of the effective methods to overcome its instability and to achieve practical applications. However, it still faces the great challenges of low photoluminescence quantum yield (PLQY), poor thermostability and photostability at present. Herein, we successfully prepared CsPbBr3 QDs in situ within a well-designed glass matrix (CsPbBr3 QDs@glass), which exhibits symmetric narrowband emission at 523 nm with a full width at half maximum (FWHM) of 25 nm, giving a PLQY of up to 52.15 % under 455 nm excitation. Meanwhile, it can keep 45.25 % of the initial luminescence intensity at 373 K, better than that of most reported CsPbBr3 QDs@glass materials. As a demonstration of a conceptual application, a white LED backlight strip was fabricated at home by encapsulating CsPbBr3 QDs@glass composite and K2SiF6:Mn4+ red phosphor on blue chips with silicone, achieving a wide color gamut of 128.6 % and 95.8 % of NTSC and Rec. 2020 color gamut, respectively. The assembled CsPbBr3 QDs@glass-based LCD screen exhibits excellent color reproduction and color saturation. All these results demonstrate that this CsPbBr3 QDs@glass composite material is a promising green emitter for wide color gamut LCD display.