Enhanced Electroluminescence from a Thiophene-Based Insulated Molecular Wire

Gábor Méhes; Chengjun Pan; Fatima Bencheikh; Li Zhao; Kazunori Sugiyasu; Masayuki Takeuchi; Jean-Charles Ribierre; Chihaya Adachi

doi:10.1021/acsmacrolett.6b00205

Enhanced Electroluminescence from a Thiophene-Based Insulated Molecular Wire

ACS Macro Lett. 2016 Jul 19;5(7):781-785. doi: 10.1021/acsmacrolett.6b00205. Epub 2016 Jun 13.

Authors

Gábor Méhes^{1

2}, Chengjun Pan³, Fatima Bencheikh², Li Zhao², Kazunori Sugiyasu³, Masayuki Takeuchi³, Jean-Charles Ribierre^{2

4}, Chihaya Adachi^{1

2

4

5}

Affiliations

¹ Fukuoka i3-Center for Organic Photonics and Electronics Research (i3-OPERA), Fukuoka 819-0388, Japan.
² Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Fukuoka 819-0395, Japan.
³ Organic Materials Group, Polymer Materials Unit, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
⁴ Japan Science and Technology Agency (JST), ERATO, Adachi Molecular Exciton Engineering Project, Fukuoka 819-0395, Japan.
⁵ International Institute for Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, Fukuoka 819-0395, Japan.

PMID: 35614772
DOI: 10.1021/acsmacrolett.6b00205

Abstract

We report on the realization of polymer light-emitting diodes (PLEDs) based on fluorescent polythiophene (PT)-based insulated molecular wires (IMWs). PLEDs using PT emitting layers traditionally have low external quantum efficiencies (η_eqe) below 0.1%. Moreover, IMWs lack a thorough exploitation for electroluminescent applications due to concerns about reduced charge transport between their chains. We constructed multilayer PLEDs containing PT IMW emitting layers that show the maximum η_eqe close to 1.4%, luminance at 3700 cd/m², and low turn on voltage at 2.5 V. We also show a strong influence of the thickness of electron transport layer on η_eqe through device optimization and optical simulations.