Elevating red emission: Yb3+ doped CsPbBr1I2 nanocrystal glass for exceptional PLQY and stability in wide color gamut backlit displays

As display technologies progress towards enhanced visual performance, there was a growing demand for color conversion materials to meet increasingly stringent performance requirements. In recent years, all-inorganic perovskite CsPbX 3 (X = Cl, Br, I) nanocrystals (NCs) had gained attention in the field of wide color gamut backlight displays due to their tunable full spectrum, narrow-band emission, high color purity, and ease of processing. However, red-emitting perovskite NCs were still facing challenges with photoluminescence quantum yield (PLQY) and stability. In this study, Yb 3+ doped CsPbBr 1 I 2 perovskite nanocrystal glass (Yb 3+ @CsPbBr 1 I 2 PNG) was synthesized using a melt-quenching technique. Samples emitting at a narrow band centered at 630 nm, with a full width at half maximum(FWHM) of 31.8 nm, exhibited a high PLQY of 80.36 % and retained fluorescence intensity at 98.2 % of the initial value in water, maintaining to 92.6 % after continuous blue light irradiation for 60 days. Moreover, the optical conversion film Yb 3+ @CsPbBr 1 I 2 @CsPbBr 3 @PET developed in our study showcased color gamut coverage surpassing 132.9 % of the NTSC 1953 standard and 98.8 % of the Rec.2020 standard. In summary, the highly efficient and remarkably stable red-emitting Yb 3+ @CsPbBr 1 I 2 PNG composite material introduced in this study paved the way for future advancements in wide color gamut and ultra-high definition backlight display technologies.