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Electrophoretic deposition (EPD) is a facile technique to deposit quantum dots (QDs) films, which can be used as the color conversion layers for display applications. To better understand the EPD process, researchers have built many models of the EPD process. However, most of these models lack solid experimental support. Here, by adopting simple yet effective solvent engineering and well-designed experiments, this study proves the Cordelair-Greil model on EPD processes. Moreover, some supplements about this model are made according to practical experiments. The experimental verification of the Cordelair-Greil model is a solid step toward revealing the dynamics of the EPD process. Furthermore, the formation of cracks in EPD deposited QD films is prevented through solvent engineering. This work proves that besides modifying the intrinsic properties of QDs, solvent engineering is also a simple, effective, and low-cost way to study the EPD process and improve the QD film qualities deposited., (© 2022 Wiley-VCH GmbH.)

Quantum dot light‐emitting diodes (QLEDs) is one of the most important components in the display field, and different structures have a certain impact on the final performance of the device. Previous QLEDs mainly use ZnO nanocrystals as the electron transport layer (ETL), but the chemical activity of ZnO nanocrystals under electric fields and moisture is not stable enough. To solve this problem, this paper studies the effects of TiO2 films with different thicknesses on the luminescence, current density and external quantum efficiency of QLED devices by using magnetron sputtered TiO2 as a new ETL. The experimental results show that the 50nm TiO2 film achieves the highest external quantum efficiency while maintaining favorable current density and brightness. [ABSTRACT FROM AUTHOR]

This paper introduces a flexible and uniformly‐dispersed quantum dot (QD) color filter (QDCF) fabricated for micro‐LED by photolithography. We studied the condition of PET films and concentration of QDs, the optimized QDCF exhibited high quantum yield (QY) up to over 70%, and a high optical density (OD) over 1.2. The QY increased and then decreased with the increase of the concentration. [ABSTRACT FROM AUTHOR]

In this report, ZnSeTe‐based blue bottom‐emitting quantum dot light‐emitting diodes (QLEDs) with optical microcavity design were demonstrated. The microcavity is formed by the top reflective Ag electrode and the bottom semi‐transparent multilayer electrode, ITO/Ag/ITO. The conventional normal QLED device structure is sandwiched between microcavity. The results show the full width at half maximum (FWHM) of the device emission spectrum is reduced to 50% compared to the device without microcavity, and the tail at longer emission wavelengths is notably suppressed. [ABSTRACT FROM AUTHOR]

Quantum dot light‐emitting diodes (QLEDs) have recently demonstrated great potential for next‐generation displays. By optimizing the device structure and film thicknesses, we achieved top‐emitting QLED devices with good performance metrics, including high brightness, efficiency, and low turn‐on voltage. Furthermore, we successfully fabricated single‐color active‐matrix quantum dot light emitting diode (AMQLED) micro display devices by integrating QLED with a Complementary Metal–Oxide– Semiconductor (CMOS) backplane. These devices exhibit high resolution, brightness, and image quality, underscoring the significant commercial value of QLED micro display devices in head‐mounted augmented reality/virtual reality (AR/VR) systems. [ABSTRACT FROM AUTHOR]

We report a 0.39‐in. quantum dot light‐emitting diode (QLED) microdisplay with full high‐definition (FHD, 1920 × 1080) resolution by integrating a red top‐emitting QLED on a complementary metal–oxide–semiconductor (CMOS) backplane. By optimizing the microcavity structure and constructing a suitable energy‐level structure for the QLED devices, the performance of the large‐area (4.9 × 8.7 mm2) top‐emitting device with normal structure reached 13,936 cd/m2 of brightness at 5‐V bias with 13.3% external quantum efficiency (EQE). Notably, the optimal device showed a low turn‐on voltage of 1.7 V, which matched well the voltage output of the CMOS backplane. Our work demonstrates the great promise of QLED microdisplays for applications in head‐mounted augmented reality/virtual reality (AR/VR). [ABSTRACT FROM AUTHOR]

Inkjet printing as an effective patterning deposition technology is very suitable for the fabrication of quantum dot light‐emitting diodes in next‐generation displays. However, there are still many challenges in achieving high efficiency and stability of the printed device. Herein, we reported the inkjet‐printed quantum dot light‐emitting diodes with an external quantum efficiency of over 20% and half lifetime at 1000 cd/m2 of 27,000 h for the first time. Such excellent performance is owing to the successfully optimal thickness (seven monolayers) of the extra ZnS shell, which improves the balance of the carries injection to suppress the nonradiative process for inkjet‐printed devices. Overall, this performance from inkjet‐printed quantum dot light‐emitting diodes accelerates the printed device to meet the requirements of practical display and lighting applications. [ABSTRACT FROM AUTHOR]

This work demonstrated color-conversion layers of red and green quantum dots color filter for full-color display arrays. Ligands exchange using (3-glycidyloxypropyl) trimethoxysilane with epoxy functional groups to treat QDs in the liquid phase was performed for photolithography use. The combination of ligands of QDs with photo-initiator played a protective role on QDs. Moreover, the pixel size of green QDCF can be reduced to 50 μm, and a high optical density (OD) of 1.2 is realized. [ABSTRACT FROM AUTHOR]

This article discusses the aging behavior of Quantum Dot Light-Emitting Diodes (QLEDs) that use sputtered TiO2 as the Electron Transport Layer (ETL). The authors explain that while there have been advancements in improving the efficiency and lifetime of QLEDs, controlling and predicting device characteristics during storage and operation remains challenging. To address this issue, the authors introduced a sputtered TiO2 film as an alternative ETL, which offers promise in resolving these challenges. The findings indicate that devices incorporating a sputtered TiO2 film as the ETL exhibit a controllable and predictable aging curve, with a lower acceleration factor compared to conventional QLEDs. [Extracted from the article]

The emergence of optical Internet of Things (optical-IoT) for sixth-generation (6G) networks has been envisaged to relieve the bandwidth congestion in the conventional radio frequency (RF) channel, and to support the ever-increasing number of smart devices. Among the plethora of device innovations deemed essential for fortifying the development, herein we report on the visible-to-near-infrared color-conversion luminescent-dyes based on lead sulphide quantum dots (PbS QDs), so as to achieve an eye-safe high-speed optical link. The solution-processed PbS QDs exhibited strong absorption in the visible range, radiative recombination lifetime of 6.4 μs, as well as high photoluminescence quantum yield of up to 88%. Our proof-of-principle demonstration based on an orthogonal frequency-division multiplexing (OFDM) modulation scheme established an infrared data transmission of 0.27 Mbit/s, readily supporting an indoor optical-IoT system, and shed light on the possibility for PbS-integrated transceivers in supporting remote access control of multiple nodes. We further envisaged that our investigations could find applications in future development of solution-processable PbS-integrated luminescent fibers, concentrators, and waveguides for high-speed optical receivers. [ABSTRACT FROM AUTHOR]

Using blue Micro‐LED back light and red‐green quantum dot (QD) color converter (QDCC) is a full color display technology with great potential to achieve high resolution, color purity and luminous efficiency. In this work, we try a new method of ligands exchange, using 3‐Mercaptopropionic acid (MPA) ligands with two functional groups to treat QDs in the liquid phase. The modified QDs can be sufficiently dispersed in the negative‐tone molecular resists. In our current process, the pixel size can be reduced to 5 fim and the large‐area ultra‐high‐resolution QDCC with great uniformity is realized. [ABSTRACT FROM AUTHOR]