Charge injection engineering at organic/inorganic heterointerfaces for high-efficiency and fast-response perovskite light-emitting diodes

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Oct. 13, 2023

The development of advanced perovskite emitters has considerably improved the performance light-emitting diodes (LEDs). However, further LEDs requires ideal device electrical properties, which strongly depend on its interfaces. In with conventional p-i-n structures, hole injection is generally less efficient than electron injection, causing charge imbalance. Furthermore, popular structure NiOx/poly(9-vinylcarbazole) suffers from several issues, such as weak interfacial adhesion, high trap density and mismatched energy levels. this work, we insert a self-assembled monolayer [2-(9H-carbazol-9-yl)ethyl]phosphonic acid between NiOx poly(9-vinylcarbazole) layers to overcome these challenges at organic/inorganic heterointerfaces by establishing robust interface, passivating states aligning We successfully demonstrate blue (emission 493 nm) green 515 devices external quantum efficiencies 14.5% 26.0%, respectively. More importantly, also gives rise much faster response speeds reducing capacitance resistance. Our results pave way for developing more brighter quick response, widening their potential application scope.

Language: Английский

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Enhancing Light Outcoupling Efficiency via Anisotropic Low Refractive Index Electron Transporting Materials for Efficient Perovskite Light‐Emitting Diodes

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(24)

Published: March 2, 2024

Abstract Thanks to the extensive efforts toward optimizing perovskite crystallization properties, high‐quality films with near‐unity photoluminescence quantum yield are successfully achieved. However, light outcoupling efficiency of light‐emitting diodes (PeLEDs) is impeded by insufficient extraction, which poses a challenge further advancement PeLEDs. Here, an anisotropic multifunctional electron transporting material, 9,10‐bis(4‐(2‐phenyl‐1H‐benzo[d]imidazole‐1‐yl)phenyl) anthracene (BPBiPA), low extraordinary refractive index ( n e ) and high mobility developed for fabricating high‐efficiency The molecular orientations BPBiPA can result in 1.59 along z ‐axis direction. Optical simulations show that effectively mitigate surface plasmon polariton loss enhance photon extraction waveguide mode, thereby improving In addition, facilitate balanced carrier injection As result, green PeLEDs record external 32.1% current 111.7 cd A −1 obtained, provides new inspirations design materials high‐performance

Language: Английский

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Perovskite Quantum Dots for the Next‐Generation Displays: Progress and Prospect

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(36)

Published: March 5, 2024

Abstract The “Nobel Prize in Chemistry 2023” is awarded to Moungi G. Bawendi, Louis E. Brus, and Alexey I. Yekimov for discovering synthesizing Quantum Dots (QDs). Colloidal QDs possess fascinating size‐, morphological‐, composition‐, assembly‐tunable electronic optical properties, which makes them star materials various optoelectronic applications, especially as luminescent next‐generation wide color gamut ultra‐high‐definition displays. Perovskite (PQDs) have gained widespread attention recent years. In less than ten years, research on perovskite‐related devices has basically been perfected terms of quantum yield external efficiency (EQE). However, the eve its industrial application, some key technical indicators processes need be met resolved. development transformation QD then focuses progress luminescence linewidth EQE PQD light‐emitting diode. Finally, several application avenues are reviewed PQDs, challenges opportunities field proposed.

Language: Английский

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Eliminating Chlorine Vacancies of Perovskite Nanocrystals Using Hydrazine Cations Enables Efficient Pure Blue Light-Emitting Diodes

ACS Energy Letters, Journal Year: 2024, Volume and Issue: 9(3), P. 1210 - 1218

Published: Feb. 26, 2024

Mixed Br/Cl-perovskite nanocrystals (Pe-NCs) CsPbBrxCl3–x, synthesized at room temperature (RT), offer several advantages for use in light-emitting diodes (LEDs), including cost-effective processing and a narrow luminescence peak. However, achieving efficient pure blue LEDs using CsPbBrxCl3–x NCs has been proven to be challenging due significant number of chlorine defects. In this work, we propose passivation strategy utilizing hydrazine cations (Hz2+) eliminate defects RT-synthesized Pe-NCs. Our investigation reveals that Hz2+ can capture the isolated anion (Cl–) form Hz–Cl–Cs bridge on Pe-NC surface, thereby effectively inhibiting formation vacancies. This approach significantly enhances both photoluminescence efficiency lifetime Consequently, fabricated Hz2+-passivated Pe-NCs achieve an outstanding external quantum (EQE) 7.82% 475 nm. findings highlight effective mitigates Pe-NCs, advancing development LEDs.

Language: Английский

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Highly ordered inkjet-printed quantum-dot thin films enable efficient and stable QLEDs with EQE exceeding 23%

eScience, Journal Year: 2023, Volume and Issue: 4(3), P. 100227 - 100227

Published: Dec. 29, 2023

Inkjet-printed quantum dot light-emitting diodes (QLEDs) are emerging as a promising technology for next-generation displays. However, progress in fabricating QLEDs using inkjet printing technique has been slower compared to spin-coated devices, particularly terms of efficiency and stability. The key achieving high performance lies creating highly ordered uniform inkjet-printed (QD) thin film. In this study, we present effective strategy significantly improve the quality CdZnSe/CdZnS/ZnS QD films through pressure-assisted thermal annealing (PTA) approach. Benefiting from PTA process, film with packing, low surface roughness, photoluminescence excellent electrical property is obtained. mechanism behind process its profound impact on device have thoroughly investigated understood. Consequently, record external (EQE) 23.08% an impressive operational lifetime (T50) up 343,342 h@100 cd·m−2, EQE 22.43% T50 exceeding 1,500,463 cd·m−2 achieved red green CdZnSe-based QLEDs, respectively. This work highlights important approach realize efficient stable thus advancing QLED practical applications.

Language: Английский

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Ordered Phase Distribution of Quasi‐2D Perovskites Controlled by a Supramolecular Approach Enables Efficient Blue Light‐Emitting Diodes

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(25)

Published: Feb. 21, 2024

Abstract Quasi‐2D perovskites demonstrate exceptional luminescent properties, mainly attributed to heightened radiative recombination facilitated by the energy transfer process among spontaneous quantum‐well structures featuring varied n‐value distributions. However, rapid crystallization often induces uncontrolled variations in phase composition, characterized distinct “n” values, leading suboptimal efficiency. In this study, an innovative supramolecular strategy utilizing cryptand is introduced as additive regulate distribution within quasi‐2D perovskite films. Cryptand effectively inhibited aggregation of PEA + and formation unsaturated Pb‐X coordination compounds, thereby suppressing generation low‐“n” phases. This intervention resulted a continuous series ordered intermediate phases with higher values. The graded electronic structure efficient from high‐“n” phases, promoting effective radiation recombination. As result, optimized PeLEDs emitting at 490 nm demonstrated remarkable external quantum efficiency (EQE) enhancement 10.16%, compared reference device EQE 2.33%. also exhibited impressive spectral operational stability. findings establish viable for precise regulation perovskites, offering great potential high‐performance blue PeLEDs.

Language: Английский

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Co-regulation strategy dominated by double short molecules permitting the regrowth of quantum dots for efficient deep-blue perovskite light-emitting diodes

Nano Energy, Journal Year: 2024, Volume and Issue: 121, P. 109263 - 109263

Published: Jan. 4, 2024

Language: Английский

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Ligand‐Pinning Induced Size Modulation of CsPbI₃ Perovskite Quantum Dots for Red Light‐Emitting Diodes

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(44)

Published: July 16, 2024

Abstract Perovskite quantum dots (PQDs) show high potential for new‐generation light‐emitting diodes (LEDs) due to their outstanding optoelectronic properties. Even though the red PQD‐LEDs can be realized through mixing halide in PQDs tune spectroscopies, may suffer from phase separation under a electric field, predominantly affecting LED applications. Herein, ligand‐pinning‐assisted approach is reported spectroscopies of CsPbI 3 PQDs, which vinyl phosphonic acid (VPA) applied as function ligands regulate nucleation and growth during synthesis. Systematically experimental studies theoretical calculations are conducted comprehensively understand functions VPA PQD synthesis, reveals that with binding energy Pb 2+ cations could firmly anchor on surface matrix without desorption, regulating thus resulting tunable being realized. Meanwhile, also renovate defective substantially diminishing trap‐induced nonradiative recombination. Consequently, deliver external efficiency 22.83%, significantly improved compared control devices. This work provides new avenue toward high‐performing LEDs.

Language: Английский

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Strategies for Stabilizing Metal Halide Perovskite Light-Emitting Diodes: Bulk and Surface Reconstruction of Perovskite Nanocrystals

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

Published: March 7, 2025

Light-emitting colloidal lead halide perovskite nanocrystals (PeNCs) are considered promising candidates for next-generation vivid displays. However, the operational stability of light-emitting diodes (LEDs) based on PeNCs is still lower than those polycrystalline films, which requires an understanding defect formation in PeNCs, both inside crystal lattice ("bulk") and at surface. Meanwhile, uncontrollable ion redistribution electrochemical reactions under LED operation can be severe, also related to bulk surface quality a well-designed device architecture boost carrier injection balance radiative recombination. In this review, we consider reconstruction by enhancing rigidity rationally selecting ligands. Degradation pathways applied voltage discussed, strategies avoid undesirable migration PeNC films. Subsequently, other critical issues hindering commercial application LEDs including toxicity Pb perovskites, scale-up deposition design active-matrix prototypes high-resolution modules.

Language: Английский

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Performance Improvement of Lead‐Based Halide Perovskites through B‐Site Ion‐Doping Strategies

Small, Journal Year: 2023, Volume and Issue: 19(36)

Published: May 5, 2023

Abstract Owing to their excellent properties, lead halide perovskites have attracted extensive attention in the photoelectric field. Presently, certified power conversion efficiency of perovskite solar cells has reached 25.7%, specific detectivity photodetectors exceeded 10 14 Jones, and external quantum perovskite‐based light‐emitting diode 26%. However, practical applications are limited by inherent instability induced structure due moisture, heat, light. Therefore, one widely used strategies address issue is replace partial ions with smaller radii shorten bond length between halides metal cations, improving energy enhancing stability. Particularly, B‐site cation can affect size eight cubic octahedrons gap. X‐site only four such voids. This review comprehensively summarizes recent progress ion‐doping for provides some perspectives further performance improvements.

Language: Английский

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