Hydrogen bonding evolution and efficient blue light emission in a series of Zn-based organic–inorganic hybrid metal halide crystals

Science China Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 17, 2025

Language: Английский

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High-efficiency perovskite light-emitting diodes enabled by introducing a LiF modification layer

Applied Physics Letters, Journal Year: 2025, Volume and Issue: 126(1)

Published: Jan. 2, 2025

Surface defect passivation and exciton regulation remain a critical challenge in perovskite light-emitting diodes (PeLEDs). Organic molecules are widely used to solve these issues. However, the high sensitivity of films molecular groups concentration limited their commercialization applications. Here, we develop facile low-cost strategy that is compatible with traditional fabrication processes PeLEDs. By depositing thin LiF layer using vacuum thermal evaporation technique, defects film effectively passivated. Simultaneously, protects excitons formed from quenching by electron-transport layer. Due synergistic effect LiF, an efficient green PeLED achieved maximum current efficiency 47.0 cd/A luminance 30 280 cd/m2, representing respective 65% 166% increase than control device without modification (28.5 11 380 cd/m2). Our work provides effective deep understanding interface for achieving high-performance

Language: Английский

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Highly Efficient Blue Light-Emitting Diodes Enabled by Gradient Core/Shell-Structured Perovskite Quantum Dots

ACS Nano, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 10, 2025

Room temperature (RT) synthesized mixed bromine and chlorine CsPbBrxCl3–x perovskite quantum dots (Pe-QDs) offer notable advantages for blue dot light-emitting diodes (QLEDs), such as cost-effective processing narrow luminescence peaks. However, the efficiency of QLEDs using these RT-synthesized QDs has been limited by inferior crystallinity deep defect presence. In this study, we demonstrate a precise approach to constructing high-quality gradient core–shell (CS) structures QD through anion exchange. Characterization shows that CS-QDs exhibit type-I band alignment with high concentration in core shell. This unique configuration results larger exciton binding energy reduced density, leading enhanced radiative recombination. Consequently, achieve an external (EQE) 16.28%, maximum luminance 8423.35 cd/m2, improved operational stability, surpassing 12.80% EQE reference made homogeneous structured (HS-QDs). These findings present strategy developing CS-QDs, marking significant advancement field efficient pure-blue QLEDs.

Language: Английский

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Phase Control and Defect Passivation via (2-Aminoethyl)phosphonic Acid-Modified PEDOT:PSS for Blue Perovskite Light-Emitting Devices

ACS Applied Nano Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 14, 2025

Achieving pure blue emission of perovskite light-emitting diodes (PeLEDs) is great importance for fulfilling full-color display and lighting applications. However, achieving high-performance PeLEDs in bromide quasi-2D (Q2D) perovskites has always been a formidable challenge. Here, an interface engineering strategy proposed to regulate the light color device photoelectric performance simultaneously by employing (2-aminoethyl)phosphonic acid (AEP)-modified poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS). The AEP-PEDOT:PSS not only enhances wettability toward precursor but also coordinates with unsaturated Pb atoms, facilitating growth nanocrystals fewer defects. Thereby, shifted from sky-blue region higher PLQY was achieved. Additionally, incorporation AEP reduces conductivity PEDOT:PSS film, enabling more balanced charge transport device. Consequently, modification achieve external quantum efficiency (EQE) 5.2%, approximately 1.9 times that control Our findings may provide valuable insights helpful guidance development Q2D LEDs.

Language: Английский

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Manipulating Phase and Defect Distribution of Quasi-2D Perovskites via a Synergistic Strategy for Enhancing the Performance of Blue Light-Emitting Diodes

ACS Applied Materials & Interfaces, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 23, 2025

Quasi-two-dimensional (quasi-2D) mixed-halide perovskites are a requisite for their applications in highly efficient blue perovskite light-emitting diodes (PeLEDs) owing to strong quantum confinement effect and high exciton binding energy. The pace of quasi-2D PeLEDs is hindered primarily by two factors: challenges precisely managing the phase distribution defect-mediated nonradiative recombination losses. Herein, we utilize 2,2-diphenylethylamine (DPEA+) with bulky steric hindrance disturb assembly process slender spacer host cation, 4-fluorophenylethylammonium (p-F-PEA+), enhancing management PeLEDs. DPEA+ not only inhibits small-n but also strengthens carrier transport alleviates quenching. In addition, dual additives─formamidine acetate (FAoAc) guanidine thiocyanate (GASCN)─were incorporated assist tailoring passivation remaining defects films. C═O SCN- groups can coordinate Pb2+ suppress charge trap density recombination. As result employing synergetic strategy comprehensive regulation defect passivation, optimized device achieves emission at 479 nm 5× improvement external efficiency (EQE) 13× increase operating stability. This paves simple route toward high-performance blue-emission

Language: Английский

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Nanocrystalline Perovskites for Bright and Efficient Light‐Emitting Diodes

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 19, 2025

Abstract Nanocrystalline perovskites have driven significant progress in metal halide perovskite light‐emitting diodes (PeLEDs) over the past decade by enabling spatial confinement of excitons. Consequently, three primary categories nanocrystalline emerged: nanoscale polycrystalline perovskites, quasi‐2D and nanocrystals. Each type has been developed to address specific challenges enhance efficiency stability PeLEDs. This review explores representative material design strategies for these correlating them with exciton recombination dynamics optical/electrical properties. Additionally, it summarizes trends decade, outlining four distinct phases development. Lastly, this addresses remaining proposes a potential further advance PeLED technology toward commercialization.

Language: Английский

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High-Performance Pure Blue Perovskite Light-Emitting Diodes with Mixed Ionic Liquid Interlayer for Micro Light-Emitting Diodes

Published: Jan. 1, 2025

Language: Английский

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Low-Voltage RGB Perovskite Light-Emitting Transistors with Magnetron Sputtered Ta2O5 High-k Dielectric Layer

Organic Electronics, Journal Year: 2025, Volume and Issue: unknown, P. 107241 - 107241

Published: March 1, 2025

Language: Английский

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Impact of Organic Spacers and Dimensionality on Templating of Halide Perovskites

ACS Energy Letters, Journal Year: 2024, Volume and Issue: 9(8), P. 3947 - 3954

Published: July 18, 2024

Two-dimensional (2D) halide perovskites (HPs) are promising materials for various optoelectronic applications; yet, a comprehensive understanding of their dynamics is still elusive. Here, we offer insight into the prototypical 2D HPs based on MAPbI3 as function linker molecule and number perovskite layers using atomic-scale simulations. We show that closest to undergo transitions distinct from those interior layers. These can take place anywhere between few tens Kelvin degrees below more than 100 K above cubic–tetragonal transition bulk MAPbI3. In combination with thickness layer, this enables one template phase tune over wide temperature range. Our results thereby reveal details an important generalizable design mechanism tuning properties these materials.

Language: Английский

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Solvent-Reconstructed Interface That Enhances Light Out-Coupling in Quasi-Two-Dimensional Perovskite Light-Emitting Diodes

Nano Letters, Journal Year: 2024, Volume and Issue: 24(23), P. 7012 - 7018

Published: May 31, 2024

Light management is critical to maximizing the external quantum efficiency of perovskite light-emitting diodes (PeLEDs), but strategies for enhancing light out-coupling are typically complex and expensive. Here, using a facile solvent treatment strategy, we create layer lithium fluoride (LiF) nanoislands that serve as template reconstruct light-extracting interfaces PeLEDs. The nanoisland interface rearranges near-field distribution in order maximize internal extraction. With proper adjustment size distribution, have achieved an optimal balance between charge injection out-coupling, resulting bright, pure-red quasi-two-dimensional PeLEDs with 21.8% peak efficiency.

Language: Английский

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