Efficient and Stable Red Perovskite Light‐Emitting Diodes via Thermodynamic Crystallization Control

Advanced Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 2, 2024

Abstract Efficient and stable red perovskite light‐emitting diodes (PeLEDs) demonstrate promising potential in high‐definition displays biomedical applications. Although significant progress has been made device performance, meeting commercial demands remains a challenge the aspects of long‐term stability high external quantum efficiency (EQE). Here, an situ crystallization regulation strategy is developed for optimizing films through ingenious vapor design. Mixed containing dimethyl sulfoxide carbon disulfide (CS 2 ) incorporated to conventional annealing, which contributes thermodynamics dominated well‐aligned cascade phase arrangement. Additionally, surface defect density minimized by CS molecule adsorption. Consequently, target exhibit smooth exciton energy transfer, reduced density, blocked ion migration pathways. Leveraging these advantages, spectrally PeLEDs are obtained featuring emission at 668, 656, 648 nm, yield record peak EQEs 30.08%, 32.14%, 29.04%, along with prolonged half‐lifetimes 47.7, 60.0, 43.7 h initial luminances 140, 250, 270 cd m −2 , respectively. This work provides universal represents stride toward commercialization PeLEDs.

Language: Английский

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Highly bright perovskite light-emitting diodes enabled by retarded Auger recombination

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 22, 2025

Abstract One of the key advantages perovskite light-emitting diodes (PeLEDs) is their potential to achieve high performance at much higher current densities compared conventional solution-processed emitters. However, state-of-the-art PeLEDs have not yet reached this potential, often suffering from severe current-efficiency roll-off under intensive electrical excitations. Here, we demonstrate bright PeLEDs, with a peak radiance 2409 W sr −1 m −2 and negligible roll-off, maintaining external quantum efficiency over 20% even as 2270 mA cm . This significant improvement achieved through incorporation electron-withdrawing trifluoroacetate anions into three-dimensional emitters, resulting in retarded Auger recombination due decoupled electron-hole wavefunction. Trifluoroacetate can additionally alter crystallization dynamics inhibit halide migration, facilitating charge injection balance improving tolerance perovskites voltages. Our findings shed light on promising future for emitters high-power applications, including laser diodes.

Language: Английский

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Polariton-Mediated Ultrafast Nonlinear Energy Transfer in a van der Waals Superlattice

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

Published: Feb. 21, 2025

Exciton-polariton dynamics in 2D materials have garnered substantial attention across diverse scientific domains for fundamental research with potential applications optoelectronics. However, practical implementation has been hindered by the challenge of maintaining stable and long-range polariton propagation. Here, we present an innovative material platform featuring extensive monolayer WS2/Al2O3 superlattices (a square a length >0.5 cm) coupled to waveguide mode designed host exciton-polaritons operation at room temperature. Time-resolved transient absorption spectra show picosecond nonlinear energy transfer phenomena between upper lower states, clarifying dynamic behavior within this quantum realm. In addition, observed population inversion two states that facilitate avenues creating polariton-based ultrafast modulators switches. This not only advances our understanding but also promotes development technologies harness these fascinating phenomena.

Language: Английский

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Realizing High Brightness Quasi‐2D Perovskite Light‐Emitting Diodes with Reduced Efficiency Roll‐Off via Multifunctional Interface Engineering

Advanced Science, Journal Year: 2023, Volume and Issue: 10(26)

Published: July 3, 2023

Quasi-2D perovskites have recently flourished in the field of luminescence due to quantum-confinement effect and efficient energy transfer between different n phases resulting exceptional optical properties. However, owing lower conductivity poor charge injection, quasi-2D perovskite light-emitting diodes (PeLEDs) typically suffer from low brightness high-efficiency roll-off at high current densities compared 3D perovskite-based PeLEDs, which is undoubtedly one most critical issues this field. In work, PeLEDs with brightness, reduced trap density, low-efficiency are successfully demonstrated by introducing a thin layer conductive phosphine oxide perovskite/electron transport interface. The results surprisingly show that additional does not improve multiple film, but purely improves electronic properties On hand, it passivates surface defects film; on other promotes electron injection prevents hole leakage across As result, modified pure Cs-based device shows maximum > 70,000 cd m-2 (twice control device), external quantum efficiency (EQE) 10% much bias voltages.

Language: Английский

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From lab to luminescence: Perovskite-based dimensional integrations pushing LED boundaries

Materials Today Physics, Journal Year: 2024, Volume and Issue: 46, P. 101490 - 101490

Published: June 22, 2024

Language: Английский

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Modulation of Charge Transport Layer for Perovskite Light‐Emitting Diodes

Advanced Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 23, 2024

Abstract Perovskite light‐emitting diodes (Pero‐LEDs) have garnered significant attention due to their exceptional emission characteristics, including narrow full width at half maximum, high color purity, and tunable colors. Recent efficiency operational stability advancements positioned Pero‐LEDs as a promising next‐generation display technology. Extensive research review articles on the compositional engineering defect passivation of perovskite layers substantially contributed development multi‐color high‐efficiency Pero‐LEDs. However, crucial aspect charge transport layer (CTL) modulation in remains relatively underexplored. CTL not only impacts carrier injection balance but also plays critical role passivating surface, blocking ion migration, enhancing crystallinity, improving light extraction efficiency. Therefore, optimizing CTLs is pivotal for further Pero‐LED performance. Herein, this discusses roles categorizes both reported potential materials. Then, various optimization strategies are presented, alongside an analysis selection criteria high‐performance Finally, summary outlook advance performances provided.

Language: Английский

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Strategic Buried Defect Passivation of Perovskite Emitting Layers by Guanidinium Chloride for High‐Performance Pure Blue Perovskite Light Emitting Diodes

Small, Journal Year: 2024, Volume and Issue: unknown

Published: June 12, 2024

Abstract Perovskite light‐emitting diodes (PeLEDs) show promise for high‐definition displays due to their exceptional electroluminescent properties. However, the performance of pure blue PeLEDs is hindered by unfavorable ionic behavior halides and presence defective antisites in blue‐emitting perovskite materials. An unstable buried interface between charge transport layers emitting layer a major issue that limits carrier recombination PeLEDs. In this study, effective defect passivation introducing guanidinium chloride (GACl) as bottom‐passivating demonstrated. The GACl bottom not only passivates point defects present at but also provides anions suppress ion migration halide vacancy formation. Along with passivation, enforces phase purity 2D layered structure improve crystallinity optoelectronic As result, high brightness (1200 cd m −2 ) excellent external quantum efficiency (6.61%) are achieved spectrally stable electroluminescence 471 nm (band width = 17.63 nm). This study offers insights into straightforward way preparing high‐performance

Language: Английский

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Reduced‐Dimensional Perovskites: Quantum Well Thickness Distribution and Optoelectronic Properties

Advanced Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 19, 2024

Abstract Reduced‐dimensional perovskites (RDPs), a large category of metal halide perovskites, have attracted considerable attention and shown high potential in the fields solid‐state displays lighting. RDPs feature quantum‐well‐based structure energy funneling effects. The multiple quantum well (QW) endows with superior transfer luminescence efficiency. effect QW confinement directly depends on number inorganic octahedral layers (QW thickness, i.e., n value), so distribution values determines optoelectronic properties RDPs. Here, it is focused thickness RDPs, detailing its structural characteristics, carrier recombination dynamics, properties, applications light‐emitting diodes. reported control strategies also summarized discuss current challenges future trends This review aims to provide deep insight into hope advancing their further development applications.

Language: Английский

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Defect Passivating Hole Transporting Material for Large-Area and Stable Perovskite Quantum-Dot Light-Emitting Diodes

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

Published: Feb. 11, 2025

Organic hole-transporting materials (HTMs) with high hole mobility and a defect passivating ability are critical for improving the performance stability of perovskite optoelectronics, including quantum dot light-emitting diodes (Pe-QLEDs) solar cells. In this study, we designed two small-molecule HTMs, termed X13 X15, incorporating methylthio group (SMe) as defect-passivating sites to enhance interaction between HTMs layer Pe-QLED applications. Our study highlights that featuring SMe groups at para-position carbazole unit, demonstrates strong superior passivation effects dots. Consequently, Pe-QLEDs (0.09 cm2) X15 HTM achieve maximum external efficiency (EQE) 22.89%. Moreover, employing in large-area (1 yields an EQE 21.10% uniform light emission, surpassing PTAA-based devices (EQE ∼ 15.03%). finding provides crucial insights into molecular design related optoelectronic devices.

Language: Английский

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Role of Small Organic Molecules in Perovskite Light‐Emitting Diodes: Applications, Mechanisms and Prospects

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

Published: Feb. 10, 2025

Abstract Perovskite light‐emitting diodes (PeLEDs) has emerged as one of the most promising technologies for next generation lighting and high‐definition display applications due to their exceptional color purity, tunable emission, low material costs. In past eleven years, PeLEDs have made remarkable progress researchers come up with many innovative approaches. Among them, additive engineering based on small organic molecules (SOMs) been demonstrated effective strategies enhance external quantum efficiency (EQE) stability PeLEDs. Notably, champion EQEs red, green, blue devices cannot be realized without participation SOMs. Here, this paper first reviews development PeLEDs, followed by a focused discussion specific application mechanism SOMs in Lastly, it analyzes challenges provides an outlook future development.

Language: Английский

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