Ultrastable glass-protected all-inorganic perovskite quantum dots with finely tunable green emissions for approaching Rec. 2020 backlit display

CsPbX3 (X = Cl, Br, I) perovskite quantum dots (PeQDs) have potential application in backlit display. However, they generally suffer from instability and shortage of ultrapure tunable green emissions owing to halogen phase separation. This work reports the realization of elaborately tunable green emissions in glass-protected CsPb(Br/I)3 PeQDs, which show the advantage of superior long-term stability and enable them to find promising application in ultra-high definition televisions. CsPbX3@glass composites are fabricated by a facile in-situ glass crystallization strategy and their emissions within the spectral range of 506–532 nm along with narrow full width at half maximum (FWHM) of ~21 nm can be well modified by simply varying Br-to-I ratio in precursor glass. Benefited from the protection of tight glass network, CsPbX3@glass retains 90% luminescence after immersing in water for one month, shows no any loss of luminescence after irradiation by 450 nm LED light and prevents anion-exchange and phase separation completely. As a proof-of-concept experiment, CsPbX3@glass-based on-chip white LED devices are constructed and applied in backlit display, covering up 123% and 92% color gamut of NTSC and Rec. 2020 standards in the CIE 1931 color space, respectively.