Environmental-Friendly Cs₃Mn_xZn_(1–x)Br₅@PS Films Used for Wide Color Gamut Backlight Displays

Abstract

In recent years, all-inorganic metal lead halide cesium perovskites (CsPbX 3 , X = Cl, Br, and I) have shown excellent luminescence performance in the field of wide color gamut backlight displays. However, Pb 2+ in CsPbX 3 easily leaks because of the unstable structure of CsPbX 3 , which seriously threatens human health. However, Mn-based metal halides (MHs) have unique environmentally friendly characteristics. In this work, Zn 2+ -doped Cs 3 MnBr 5 MHs were successfully prepared, which exhibited highly efficient green emissions at 520−522 nm. Moreover, Cs 3 Mn x Zn (1−x) Br 5 shows excellent stability at room temperature (25 °C) compared with Cs 3 MnBr 5 . More excitingly, when Cs 3 Mn x Zn (1−x) Br 5 was encapsulated in a polystyrene (PS) polymer, Cs 3 Mn x Zn (1−x) Br 5 @PS showed better water, acid, daylight, and blue light stabilities. In addition, the backlight display device was designed based on different green−red ratios and thicknesses of Cs 3 Mn x Zn (1−x) Br 5 @K 2 SiF 6 :Mn 4+ @PS light conversion films, and the color gamut was over 109% of the NTSC 1953 standard, which is better than that of the reported WLED devices based on Mn-based MHs thus far. This work undoubtedly shows that Mn-based MHs have great application potential in wide color gamut backlight displays and provide a practicable route to fabricate nontoxic, low-cost, and high-performance liquid crystal displays. KEYWORDS: Cs 3 Mn x Zn (1−x) Br 5 , PS, stability, color gamut, backlight display

Ag Nanoparticles Optimized the Optical Properties and Stability of CsPbBrI2 Glass for High Quality Backlight Display

“…In order to further improve the stability of CPBIG powder and adapt to the technical requirements of backlight display, CPBI QDs are double-coated with polymer materials. As the most promising polymer material, PS was selected for use in the industrial production of backlight films. , On the one hand, a series of Ag@CPBIG@PS films was prepared by dissolving PS masterbatch using toluene solvent and then adding 0.01, 0.03, 0.05, 0.07, and 0.09 g red glass powder to 1.0 g of PS masterbatch, respectively (see Figure S7a for sample images). The PL spectrum of the composite films prepared by SM is shown in Figure a.…”

Stability Enhancement of CsPbBrI2 Glass Powder in PS Film via a Heat-Water Cyclic Treatment for Backlight Display

“…As displayed in Figure b, the PL intensity of the film reaches the highest when the content of RGP6 is 4.00%. At this point, the RGP6 in PS polymer reaches the saturation state, and when the glass powder content is added to 5.00%, the RGP6 appears in film agglomeration, resulting in a decrease in the PL intensity of the film . Following this, a set of RGP@PS with a content of 4.00% was made.…”

Regulating the Optical Properties of Cs3MnBr5 Nanocrystals in Glasses for Narrow-Band Green Emission

“…Mn-based halides have attracted considerable interest for many photoelectronic applications, due to their superior properties such as a large Stokes shift, a long lifetime, high efficiency, non-toxicity, as well as multiple absorption bands and high absorption coefficient in the visible spectral range. , Recently, great progress has been made on organic–inorganic hybrid manganese halides with bright green PL featuring a high PL QY of ∼100%, tunable PL (510–550 nm), and a narrow PL band (30–50 nm). , The WLED fabricated using C 4 H 12 NMnCl 3 and (C 8 H 20 N) 2 MnBr 4 phosphors can generate a wide color gamut up to 104% of NTSC and a high luminous efficiency of 96 lm/W, confirming that Mn-based halides are competitive candidates for green light-emitting materials . However, due to the enhanced electronic interactions and non-radiative energy transfer between neighboring units induced by the high Mn 2+ concentration and the short separation between neighboring units, Mn-based halides usually undergo serious PL quenching. , Obviously, separation between neighboring units can be more easily adjusted for organic–inorganic hybrid manganese halides by selection of proper A-site cations and a spatial configuration, leading to enhanced PL QY. ,, However, it is difficult for all inorganic cesium manganese halides to find larger A-site cations to enlarge the separation between neighboring units, which makes PL QYs of all inorganic cesium manganese halides inferior to those of organic–inorganic hybrid Mn-based halides. − Incorporation of other B-site cations (such as Zn 2+ , Cd 2+ , and rare-earth ions) into cesium manganese halides, reducing the effective concentration of Mn 2+ ions in Mn-based halides, or building up an energy transfer channel from the host to luminescent dopants instead of neighboring units are useful strategies to enhance their PL QY. − At present, Cs 3 MnBr 5 phosphors and colloidal Cs 3 MnI 5 NCs have achieved efficient green PL with PL QYs of 49 and 73%, respectively. , However, due to the ionic structure, Mn-based halides are sensitive to humidity and oxygen, , hindering their potential applications. Postsynthetic encapsulation employed to improve the stability generally involves mixing nano- and microcrystalline compounds with organic polymers.…”