{"title":"A pyrimidine end-capped electron transport material interacted with silver for improving electron-injection and long-term stability in OLEDs†","authors":"Yuhui Chen, Takeshi Sano, Hisahiro Sasabe, Ryo Sugiyama, Amane Matsunaga, Hiroki Sato, Hiroshi Katagiri and Junji Kido","doi":"10.1039/D4TC03534H","DOIUrl":null,"url":null,"abstract":"<p >Although organic light-emitting devices (OLEDs) have been commercialized for display applications, electron-injection layers (EILs) still rely on alkali metals or their compounds to lower driving voltages, and hence reactivity with atmospheric moisture is a primary concern, especially in flexible devices. As an alternative strategy, combining electron transport materials (ETMs) based on 1,10-phenanthroline (Phen) derivatives with silver (Phen/Ag) has attracted much attention for developing air-stable EILs. However, most studies have focused on Phen derivatives. Herein, we developed a non-Phen ETM named <strong>DPmPy-BP</strong> based on a 2,6-di(pyrimidin-2-yl)pyridine skeleton. Combined with Ag (<strong>DPmPy-BP</strong>/Ag) as a potentially air-stable EIL, this ETM exhibited superior electron-injection properties and remarkable stability in preliminary green phosphorescent OLEDs achieving a maximum external quantum efficiency (EQE) of 20% and an operational lifetime (LT<small><sub>50</sub></small>) of approximately 17 000 hours at 1000 cd m<small><sup>−2</sup></small>, which surpass those of <strong>Phen</strong>/Ag devices and are comparable to devices using a conventional alkali metal compound 8-hydroxyquinolinolato-lithium (<strong>Liq</strong>) as the EIL (<strong>DPmPy-BP</strong>/<strong>Liq</strong>).</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 47","pages":" 19274-19280"},"PeriodicalIF":5.7000,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Materials Chemistry C","FirstCategoryId":"1","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2024/tc/d4tc03534h","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Although organic light-emitting devices (OLEDs) have been commercialized for display applications, electron-injection layers (EILs) still rely on alkali metals or their compounds to lower driving voltages, and hence reactivity with atmospheric moisture is a primary concern, especially in flexible devices. As an alternative strategy, combining electron transport materials (ETMs) based on 1,10-phenanthroline (Phen) derivatives with silver (Phen/Ag) has attracted much attention for developing air-stable EILs. However, most studies have focused on Phen derivatives. Herein, we developed a non-Phen ETM named DPmPy-BP based on a 2,6-di(pyrimidin-2-yl)pyridine skeleton. Combined with Ag (DPmPy-BP/Ag) as a potentially air-stable EIL, this ETM exhibited superior electron-injection properties and remarkable stability in preliminary green phosphorescent OLEDs achieving a maximum external quantum efficiency (EQE) of 20% and an operational lifetime (LT50) of approximately 17 000 hours at 1000 cd m−2, which surpass those of Phen/Ag devices and are comparable to devices using a conventional alkali metal compound 8-hydroxyquinolinolato-lithium (Liq) as the EIL (DPmPy-BP/Liq).
虽然有机发光器件(oled)已经商业化用于显示应用,但电子注入层(EILs)仍然依赖碱金属或其化合物来降低驱动电压,因此与大气湿度的反应性是一个主要问题,特别是在柔性器件中。以1,10-菲罗啉(Phen)衍生物为基础的电子传输材料(etm)与银(Phen/Ag)相结合是开发空气稳定电子传输材料的一种替代策略。然而,大多数研究都集中在苯的衍生物上。在此,我们基于2,6-二(嘧啶-2-基)吡啶骨架开发了一种名为DPmPy-BP的非苯基ETM。与Ag (DPmPy-BP/Ag)结合作为潜在的空气稳定EIL,该ETM在初步的绿色磷光oled中表现出优异的电子注入性能和显著的稳定性,在1000 cd m−2下实现了20%的最大外量子效率(EQE)和约17000小时的工作寿命(LT50)。超过了Phen/Ag器件,与使用传统碱金属化合物8-羟基喹啉-锂(Liq)作为EIL的器件(DPmPy-BP/Liq)相当。
期刊介绍:
The Journal of Materials Chemistry is divided into three distinct sections, A, B, and C, each catering to specific applications of the materials under study:
Journal of Materials Chemistry A focuses primarily on materials intended for applications in energy and sustainability.
Journal of Materials Chemistry B specializes in materials designed for applications in biology and medicine.
Journal of Materials Chemistry C is dedicated to materials suitable for applications in optical, magnetic, and electronic devices.
Example topic areas within the scope of Journal of Materials Chemistry C are listed below. This list is neither exhaustive nor exclusive.
Bioelectronics
Conductors
Detectors
Dielectrics
Displays
Ferroelectrics
Lasers
LEDs
Lighting
Liquid crystals
Memory
Metamaterials
Multiferroics
Photonics
Photovoltaics
Semiconductors
Sensors
Single molecule conductors
Spintronics
Superconductors
Thermoelectrics
Topological insulators
Transistors