摘要
有机发光材料因其低成本、可溶液加工、机械灵活性和易于调控的光电特性而备受关注,被广泛应用于有机发光二极管、有机固体激光器和荧光成像等领域.然而,有机激光增益介质普遍存在载流子迁移率低、三重态和极化子寿命长和宽吸收以及稳定性差等问题,阻碍了有机电泵浦激光的实现.通过引入大体积空间位阻基团可抑制发光分子间的相互作用,减弱材料的发光猝灭效应,有效提高发光效率.设计合成了两种具有不同空间构型的芴基寡聚物HTF和ITF,其放大自发辐射(ASE)阈值分别为6.67和12.35µJ/cm^(2).其中,寡聚物HTF展现更高的热稳定性、更小的温度依赖性和膜厚依赖性.此外,还发现溴原子的取代对二者ASE特性具有不同程度的负面影响.
Organic luminescent materials have garnered substantial attention within the scientific community owing to their notable attributes,encompassing cost-effectiveness,solution processability,mechanical flexibility,and easily adjustable optoelectronic properties.This multifaceted appeal has propelled their extensive adoption across a spectrum of applications,ranging from organic light-emitting diodes(OLEDs)and organic solid-state lasers(OSSL)to fluorescence imaging methodologies.Nevertheless,the advancement of organic electrically pumped lasers encounters significant hurdles.Organic gain media frequently grapple with challenges such as restricted charge carrier mobility,extended lifetimes of triplet states and polarons,broad absorption profiles,and inadequate stability,all of which pose substantial barriers to the practical realization of these laser systems.In response to these challenges,this study endeavors to introduce voluminous spatial hindrance groups as a prospective solution.These groups are strategically integrated to hinder intermolecular interactions among luminescent molecules,thereby alleviating the inherent luminescent quenching effects of the materials.This intervention not only augments luminescent efficiency but also fortifies the material's stability,addressing pivotal concerns within the discipline.The research methodology encompasses the design and synthesis of two distinct fluorene-based oligomers,namely HTF and ITF,each distinguished by unique spatial configurations.A meticulous examination of their amplified spontaneous emission(ASE)characteristics is conducted under diverse test conditions,incorporating dependencies on annealing temperature and film thickness.The minimum ASE thresholds for HTF and ITF are meticulously determined to be 6.67 and 12.35µJ/cm^(2),respectively.Furthermore,comparative analyses between HTF and ITF illuminate the distinctive performance attributes of each oligomer.Notably,HTF exhibits superior thermal stability,diminished temperature dependence,and reduced reliance o
作者
冯全友
张云龙
李昊
李倩意
沈建平
虞梦娜
解令海
Feng Quanyou;Zhang Yunlong;Li Hao;Li Qianyi;Shen Jianping;Yu Mengna;Xie Linghai(State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM),Nanjing University of Posts&Telecommunications,Nanjing 210023,Jiangsu Province,China;College of Electronic and Optical Engineering,Nanjing University of Post and Telecommunications,Nanjing 210023,Jiangsu Province,China)
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2024年第4期435-442,共8页
Acta Chimica Sinica
基金
国家自然科学基金(No.22375100)
浙江省柔性电子重点实验室开放基金(No.2023FE001)
有机电子与信息显示国家重点实验室(No.GZR2022010020)资助.
关键词
有机激光
放大自发辐射
增益介质
空间位阻
芴
organic laser
amplified spontaneous emission
gain media
steric hindrance
fluorene
