Revealing the interplay between charge transport, luminescence efficiency, and morphology in organic Light‐emitting diode blends

M. Gao; T. Lee; P.L. Burn; A.E. Mark; A. Pivrikas; P.E. Shaw

doi:10.1002/adfm.201907942

Back

Revealing the interplay between charge transport, luminescence efficiency, and morphology in organic Light‐emitting diode blends

Journal article

Peer reviewed

Revealing the interplay between charge transport, luminescence efficiency, and morphology in organic Light‐emitting diode blends

M. Gao, T. Lee, P.L. Burn, A.E. Mark, A. Pivrikas and P.E. Shaw

Advanced Functional Materials, Vol.30(9), 1907942

2020

DOI: https://doi.org/10.1002/adfm.201907942

Files and links (1)

url

Link to Published Version *Subscription may be requiredView

Abstract

Phosphorescent emissive materials in organic light‐emitting diodes (OLEDs) manufactured using evaporation are usually blended with host materials at a concentration of 3–15 wt% to avoid concentration quenching of the luminescence. Here, experimental measurements of hole mobility and photoluminescence are related to the atomic level morphology of films created using atomistic nonequilibrium molecular dynamics simulations mimicking the evaporation process with similar guest concentrations as those used in operational test devices. For blends of fac‐tris[2‐phenylpyridinato‐C2,N]iridium(III) [Ir(ppy)3] in tris(4‐carbazoyl‐9‐ylphenyl)amine (TCTA), it is found that clustering of the Ir(ppy)3 (surface of the molecules within ≈0.4 nm) in the simulated films is directly relatable to the experimentally‐measured hole mobility. Films containing 1–10 wt% of Ir(ppy)3 in TCTA have a mobility of up to two orders of magnitude lower (≈10−6 cm2 V−1 s−1) than the neat TCTA film, which is consistent with the Ir(ppy)3 molecules acting as hole traps due to their smaller ionization potential. Comparison of the simulated film morphologies with the measured photoluminescence properties shows that for luminescence quenching to occur, the Ir(ppy)3 molecules have to have their ligands partially overlapping. Thus, the results show that the effect of guest interactions on charge transport and luminescence are markedly different for OLED light‐emitting layers.

Details

Title: Revealing the interplay between charge transport, luminescence efficiency, and morphology in organic Light‐emitting diode blends
Authors/Creators: M. Gao (Author/Creator) - The University of Queensland
T. Lee (Author/Creator) - The University of Queensland
P.L. Burn (Author/Creator) - The University of Queensland
A.E. Mark (Author/Creator) - The University of Queensland
A. Pivrikas (Author/Creator) - Murdoch University
P.E. Shaw (Author/Creator) - The University of Queensland
Publication Details: Advanced Functional Materials, Vol.30(9), 1907942
Publisher: John Wiley & Sons Ltd.
Identifiers: 991005544058507891
Copyright: © 2019 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
Murdoch Affiliation: School of Engineering and Information Technology
Language: English
Resource Type: Journal article

UN Sustainable Development Goals (SDGs)

This output has contributed to the advancement of the following goals:

Source: InCites

Metrics

82 Record Views

35 Times Cited - Web of Science

InCites Highlights

These are selected metrics from InCites Benchmarking & Analytics tool, related to this output

Collaboration types: Domestic collaboration
Citation topics: 2 Chemistry; 2.114 Organic Semiconductors; 2.114.321 OLEDs
Web Of Science research areas: Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary; Nanoscience & Nanotechnology; Physics, Applied; Physics, Condensed Matter
ESI research areas: Materials Science