Alloyed Green-Emitting CdZnSeS/ZnS Quantum Dots with Dense Protective Layers for Stable Lighting and Display Applications

Abstract

Alloyed green-emitting CdZnSeS/ZnS quantum dots (QDs) demonstrate potential applications in solid-state lighting and displays owing to their various advantages, such as high color purity, light conversion efficiency, and color rendering index. However, their applications in white light-emitting diodes (WLEDs) are limited by their poor photostabilities on blue-emitting gallium nitride (GaN) LED chips. In this study, the effect of the specific surface area (SSA) in the coating layers on the photostabilities of QDs was investigated. SSA was adjusted by controlling the proportions of dense aluminum oxide (AlO X ) layers and porous silica dioxide (SiO2) layers to fabricate QD protective layers via a catalyst-free sol–gel method. The results showed that the synthesized AlO X possessing the lowest SSA among the synthesis protective layers presented the best QD photostabilities on the LED chips. Moreover, they exhibited a 9.9-fold increase in the operational lifetime (T 80) compared to that of pristine QDs. In addition, the QD-based WLED achieved an excellent display performance with a wide color gamut (115%) of the National Television System Committee (NTSC) color gamut standard. This approach offers a promising strategy for enhancing the QD photostabilities for applications in solid-state lighting and displays by coating the protective layers on the QD surface.

Aluminum chloride assisted synthesis of near-unity emitting Mn2+-doped CsPbCl3 perovskite nanocrystals for bright white light-emitting diodes

“…5a). 59,60 The area of the Si-O-Al bond signal is 1.4 times larger than that of the Si-O-Si bond and is predominant in the Si 2p energy spectrum, indicating that SiO 2 has successfully coated NCs. This conclusion also coincides with the fact that the Si-O-Al signal in the Al 2p XPS spectrum only appears in AlCl 3 @Mn 2+ :CsPbCl 3 /SiO 2 NCs (Fig.…”

Stretchable and Thermally Responsive Semi‐Interpenetrating Nanocomposite Hydrogel for Wearable Strain Sensors and Thermal Switch

“…[ 44 ] The presence of a thermal protection system was important for the performances and the increase in the electronic devices lifetime. [ 45 ] In this work, the conductive hydrogel can serve as a new kind of smart switch that responded to changes in the temperature to protect the electrical circuit that is shown in Figure . Compared with the commercial smart switches that need strict environmental conditions, such as no water, no acid or alkali, which restricts their applications in some special fields, [ 46 ] our smart switch can be used in watery environment.…”

InP/ZnSeS/ZnS Quantum Dot-Embedded Alumina Microbeads for Color-by-Blue Displays

“…In addition, we demonstrated that the triply protected QD-embedded microbeads improve the scattering effect as well as the operation stability and the external quantum efficiency (EQE) of the InP-based QD-microbead-dispersed film for the use of QD color converters in color-by-blue displays. Usually, high index nanoparticles, including TiO 2 , SiO 2 , and ZnO, are used as scatterer materials to enhance the absorption and emission intensities of QDs in the film-type architecture. − , QD@Al&Hf microbeads can play roles of both emissive materials and scattering materials in QD-bead-dispersed films. Therefore, we obtained a 2.86 times enhancement of luminous efficacy (LE) from our QD-bead/QD-nanoparticle-dispersed film compared to the QD-nanoparticle-dispersed film.…”

“…In addition, we demonstrated that the triply protected QDembedded microbeads improve the scattering effect as well as the operation stability and the external quantum efficiency (EQE) of the InP-based QD-microbead-dispersed film for the [41][42][43]49 QD@Al&Hf microbeads can play roles of both emissive materials and scattering materials in QD-beaddispersed films. Therefore, we obtained a 2.86 times enhancement of luminous efficacy (LE) from our QD-bead/ QD-nanoparticle-dispersed film compared to the QD-nanoparticle-dispersed film.…”