Low dimensional metal halide perovskites (MHPs) have a soft lattice, leading to strong exciton phonon coupling and exciton localization. Microstructural stiffness engineering is an effective tool for modulating the mechanical and electrical properties of materials, but its complex effects on the luminescence of low dimensional MHPs remain lacking. Here, we report microstructural stiffness engineering of low dimensional MHPs by halogen replacement in Ag-X bonds and [AgX] (X = Br, Cl) units to increase the Young's modulus from 15.
View Article and Find Full Text PDFEnergy-efficient white light-emitting diodes (LEDs) are in high demand across the society. Despite the significant advancements in the modern lighting industry based on solid-state electronics and inorganic phosphor, solid-state lighting (SSL) continues to pursue improved efficiency, saturated color performance, and longer lifetime. Here in this article, robust, narrow emission band nanorods (NRs) are disclosed with tailored wavelengths, aiming to enhance the color rendering index (CRI) and luminous efficacy (LE).
View Article and Find Full Text PDFQuantum dot (QD) light-emitting diodes (QLEDs) have attracted extensive attention due to their high color purity, solution-processability, and high brightness. Due to extensive efforts, the external quantum efficiency (EQE) of QLEDs has approached the theoretical limit. However, because of the efficiency roll-off, the high EQE can only be achieved at relatively low luminance, hindering their application in high-brightness devices such as near-to-eye displays and lighting applications.
View Article and Find Full Text PDFInorganic multicolour perovskite nanocrystals (NCs) of CsPbX (X = Cl, Br, I) with high photoluminescence (PL) quantum yield (QY) and saturated colours are considered promising candidates for a high-performance colour conversion layer. However, integration of these materials into industrial applications still faces a significant challenge due to their tendency for aggregation and quenching of the emission during deposition and processing. In this work, we explore a new ink composition with oleylamine (OLA) and hexylphosphonic acid (HPA) ligands in combination with a liquid crystal monomer (LCM) composing a superior solution for an inkjet-printed colour conversion layer.
View Article and Find Full Text PDFACS Appl Mater Interfaces
April 2022
Solution-processed semiconductor nanocrystals are evolving as potential candidates for future display and lighting applications owing to their size-tunable emission, ultrasaturated colors, and compatibility with large-area flexible substrates. Among them, quantum rods (QRs) are emerging materials for optoelectronic applications, offering polarized emission, high light outcoupling efficiency, color purity, and better stability in solid films. However, synthesizing QRs covering the full visible wavelength region has been a big challenge, particularly in the blue range.
View Article and Find Full Text PDFEfficient white light-emitting diodes (LEDs) with an efficacy of 200 lm W are much desirable for lighting and displays. The phosphor-based LEDs in use today for display applications offer poor color saturation. Intensive efforts have been made to replace the phosphor with quantum-dot-based downconverters, but the efficiency and stability of these devices are still in their infancy.
View Article and Find Full Text PDFCesium-lead halide perovskite nanoparticles are a promising class of luminescent materials for color and efficient displays. However, material stability is the key issue to solve before we can use these materials in modern displays. Encapsulation is one of the most efficient methods that can markedly improve the stability of perovskite nanoparticles against moisture, heat, oxygen, and light.
View Article and Find Full Text PDFRecently, quantum rods (QRs) have been studied heavily for display and lighting applications. QRs offer serious advantages over the quantum dots such as higher light out-coupling coefficient, and polarized emission. The QR enhancement films double liquid crystal display efficiency.
View Article and Find Full Text PDF