Xiaojuan Liang

Perovskite quantum dots (PQDs) are widely used in the backlight field of liquid crystal displays (LCDs) due to their narrow-band emission and high color purity. However, their high cost and insufficient stability seriously restrict the industrialization process. This study innovatively adopted the environmentally friendly Pb(OH)₂ to replace the traditional PbBr₂ lead source, successfully reducing the raw material cost by nearly 50%. At the same time, it significantly improved the optical performance of CsPbBr₃@glass by reducing the formation of bromine vacancies. By further introducing La³⁺, the prepared La³⁺@CsPbBr₃@glass achieved a PLQY increase from 48 to 86%, and maintained a PL intensity of 87% under harsh conditions (60 °C, 90% RH, and continuous exposure to 8000 nit blue light for 40 days), breaking through the stability bottleneck. The color gamut of the CsPbBr₃&CsPbBr₁I₂@glass@PET light conversion film developed on this basis is 94.75% of the NTSC 1953 standard and 70.74% of the Rec.2020 standard. When they are applied to LCD screens, they significantly enhance color performance. It provides an efficient, stable, and low-cost industrial solution for quantum dot film technology.

This study innovatively proposes an optically coated sapphire-based composite structure, in which a multi-functional anti-reflection/high-reflection (AR/HR) optical coating is constructed to achieve breakthrough performance in photothermal management for high-power laser lighting. The designed AR/HR coating maintains a high blue light transmittance of 94.5%, while suppressing fluorescence-band stray light by 98.82% and significantly increasing fluorescence reflectivity to 80% (compared to 15% before coating). We further developed a coated sapphire-based phosphor-in-glass film (CS-PiF). Under 450 nm blue laser excitation, this structure demonstrates an ultra-high luminous flux of 1582.7 lm, which is 1.9 times that of conventional uncoated phosphor-in-glass films (PiF), along with a peak luminous efficacy of 239 lm W⁻¹ and a thermal conductivity improved to 16.9 W m⁻¹ K⁻¹. In laser lighting application tests, the CS-PiF achieved an illuminance of 39 580 lux at a 2-meter distance, outperforming the conventional solution by a factor of 1.9. This technology breaks through the light extraction limitations of traditional phosphor converters and provides a novel solution for high-brightness solid-state laser lighting.

In this work, CsPbBr₃/Cs₄PbBr₆@glass composites were synthesized by incorporating lead carbonate (PbCO₃) into a lithium-aluminum-silicate-boron (Li-Al-Si-B) glass matrix. PbCO₃ decomposes to PbO, which reacts in situ with melt Br to form PbBr₂, triggering CsPbBr₃/Cs₄PbBr₆ nucleation in Br-rich microdomains; CO₂ release concurrently creates stress-relieving micropores, outperforming direct PbBr₂ addition. This composite exhibited remarkable photoluminescence properties, with a photoluminescence quantum yield (PLQY) reaching as high as 86.71%. In an accelerated aging experiment conducted over 120 h, the fluorescence intensity was maintained at 95% of its original value. Even after 60 days of immersion in water, the luminescence intensity remained at 94% of the initial intensity, demonstrating its outstanding resistance to environmental degradation. To further explore its potential for display applications, we prepared a CsPbBr₃/Cs₄PbBr₆/CsPbBrI₂@glass@polystyrene (PS) film. This film exhibited an impressive color gamut, covering 123% of the National Television System Committee (NTSC) 1953 standard and 91.3% of the ITU-R Recommendation BT.2020 (Rec.2020) standard. The high PLQY and excellent stability of CsPbBr₃/Cs₄PbBr₆@glass make it highly suitable for LCD applications and offer broad prospects for industrial-scale production.

The GeO₂ additive has a ‘network breaking’ effect on the network structure of silicate glass, which promotes the in situ nucleation/growth of PNCs in the glass. This effect is beneficial for reducing surface defects, and the prepared CsPbBr₃@glass has a PLQY of up to 90%.