Space-Charge-Limited Current Measurements: A Problematic Technique for Metal Halide Perovskites

The Journal of Physical Chemistry Letters, Journal Year: 2024, Volume and Issue: unknown, P. 10001 - 10008

Published: Sept. 24, 2024

Space-charge-limited current (SCLC) measurements play a crucial role in the electrical characterization of semiconductors, particularly for metal halide perovskites. Accurate reporting and analysis SCLC are essential gaining meaningful insights into charge transport defect density these systems. Unfortunately, performing on perovskites is complicated by their mixed electronic-ionic conductivity. This complexity led to data often being incorrectly analyzed using simplified models unsuitable materials reported without information about how were performed. In light recently published data, common challenges perovskite addressed, solutions discussed this paper. The applicability often-used analytical models, overlooked issues related ionic-electronic conductivity perovskites, creating single-carrier devices investigated drift-diffusion simulations. Finally, guidelines more accurate improved provided.

Language: Английский

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Increased Brightness and Reduced Efficiency Droop in Perovskite Quantum Dot Light-Emitting Diodes Using Carbazole-Based Phosphonic Acid Interface Modifiers

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

Published: Jan. 6, 2025

We demonstrate the use of [2-(9H-carbazol-9-yl)ethyl]phosphonic acid (2PACz) and [2-(3,6-di-tert-butyl-9H-carbazol-9-yl)ethyl]phosphonic (t-Bu-2PACz) as anode modification layers in metal-halide perovskite quantum dot light-emitting diodes (QLEDs). Compared to conventional QLED structures with PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrenesulfonate)/PVK (poly(9-vinylcarbazole)) hole-transport layers, QLEDs made phosphonic (PA)-modified indium tin oxide (ITO) anodes show an over seven-fold increase brightness, achieving a brightness 373,000 cd m–2, one highest brightnesses reported date for colloidal QLEDs. Importantly, onset efficiency roll-off, or droop, occurs at ∼1000-fold higher current density PA-modified compared control PEDOT:PSS/PVK hole transport allowing devices sustain significantly levels external >105 m–2. Steady-state time-resolved photoluminescence measurements indicate that these improvements are due combination multiple factors, including reducing quenching interface loss high density.

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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Effect of self-assembled monolayer on stability of perovskite LEDs

Physica B Condensed Matter, Journal Year: 2025, Volume and Issue: unknown, P. 416967 - 416967

Published: Jan. 1, 2025

Language: Английский

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Optimization of the hole-injection layer for quantum dot light-emitting diodes

Nanoscale, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

This review summarizes the optimization strategies for HILs in QLEDs, focusing on design of single HILs, dual and doped HILs. Additionally, treatment methods that can further optimize interfacial properties are discussed.

Language: Английский

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Enhanced Hole‐Injecting Interface for High‐Performance Deep‐Blue Perovskite Light‐Emitting Diodes Using Dipole‐Controlled Self‐Assembled Monolayers

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

Published: Nov. 26, 2024

The Blue electroluminescence (EL) with high brightness and spectral stability is imperative for full-color perovskite display technologies meeting the Rec. 2020 standard. However, deep-blue light-emitting diodes (PeLEDs) lag behind their green- or red-emitting counterparts in brightness, quantum efficiency, operational stability. Additionally, Cl

Language: Английский

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Balancing multiple properties of small molecule hole-transporting materials towards highly efficient perovskite QLEDs

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 500, P. 157117 - 157117

Published: Oct. 30, 2024

Language: Английский

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