One Hundred‐Nanometer‐Sized CsPbBr₃/m‐SiO₂ Composites Prepared via Molten‐Salts Synthesis are Optimal Green Phosphors for LCD Display Devices

Abstract

The exploitation of the optimal optical properties of lead halide perovskite nanocrystals in optoelectronic devices is mainly hindered by the low stability of such materials. Here, a molten‐salts approach is developed to encapsulate CsPbBr3 nanocrystals (together with KNO3, NaNO3, and KBr inorganic salts) inside different nanoscale mesoporous SiO2 host matrices, having sizes between 100 and 300 nm. The comparison between optical properties and stability of the products, including the previously reported ≥600‐nm‐sized CsPbBr3/m‐SiO2 composite, indicates that 100‐nm‐sized CsPbBr3/m‐SiO2 particles feature the best stability against humidity, light irradiation and heat, and exhibit a green (peaked at 517 nm) narrow photoluminescence (full width at half maximum of 18 nm) with high quantum yield (77%). Such properties make these composite particles optimal green phosphors for down conversion liquid crystal displays (LCDs). Indeed, the authors demonstrate that a proof‐of‐concept 7‐in. LCD in which the green color conversion layer is a polymer film loaded with 100‐nm‐sized CsPbBr3/m‐SiO2 particles, features an optimal white emission (with correlated color temperature of 6861 K), that is close to the reference white point of NTSC, and covers 92% of NTSC standard color gamut area of CIE1931, higher than that of a reference commercial LCD (Dell XPS 15 7590 laptop).

Green emission from trivalent cerium doped LaAlO3/MgO nano-composite for photonic and latent finger printing applications

“…where A is some constant. Plot of (7) in Fig. 8(f) gives slope −Q/3 which in present study yields Q to be 9.142 that is approximately equal to 10, predicting q-q multi-polar interaction to be the underlying plausible mechanism for CQ in Ce 3+ doped La 1−x -Ce x AlO 3 /MgO phosphors.…”

“…Recent years have witnessed the trend of developing and exploring nano-composite materials to solve innumerous inexorable problems including nano-phosphor composite materials. 6,7 However, the rate of research on composite phosphors is much less than the research being done on crystalline and glassy materials.…”

Near‐Infrared Persistent Phosphor‐Mediated Smart Sensing Light‐Emitting Diodes for Advanced Driver Assistance Systems

“…Phosphor‐converted light‐emitting diodes (pc‐LEDs) have recently attracted enormous attentions because of their applicability in the development of illumination sources, [ 1 ] signal lamps, [ 2 ] displays, [ 3 ] plant supplementary lightings, [ 4 ] and backlights. [ 5 ] The prerequisite for this application is the use of phosphors with high photoluminescent quantum yield (PLQY).…”

Facile Synthesis of Highly Emissive All-Inorganic Manganese Bromide Compounds with Perovskite-Related Structures for White LEDs

“…Recently, metal halide perovskites have gained enormous attention as luminescent materials for lighting and displays, owing to their high quantum yield, color tunability, and narrow emission features [ 17 , 18 , 19 , 20 , 21 ]. Despite these fascinating characteristics, nearly all high-performance perovskites contain heavy metal lead, which poses a great threat to the ecological environment and human health.…”