Molecular‐Barrier‐Enhanced Aromatic Fluorophores in Cocrystals with Unity Quantum Efficiency

作     者：Huanqing Ye Guangfeng Liu Sheng Liu David Casanova Xin Ye Xutang Tao Qichun Zhang Qihua Xiong 

作者机构：Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link 637371 Singapore Singapore School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue 639798 Singapore Singapore IKERBASQUE—Basque Foundation for Science 48013 Bilbao Euskadi Spain Donostia International Physics Center (DIPC) & Kimika Fakultatea Euskal Herriko Unibertsitatea (UPV/EHU) Paseo Manuel Lardiazabal 4 20018 Donostia Euskadi Spain State Key Laboratory of Crystal Materials Shandong University Jinan Shandong 250100 P. R. China Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link 637371 Singapore Singapore NOVITAS Nanoelectronics Center of Excellence School of Electrical and Electronic Engineering Nanyang Technological University 639798 Singapore Singapore MajuLab CNRS-UNS-NUS-NTU International Joint Research Unit UMI 3654 Singapore Singapore 

出 版 物：《Angewandte Chemie》 

年 卷 期：2018年第130卷第7期

学科分类：081704[工学-应用化学] 08[工学] 0817[工学-化学工程与技术] 

主　　题：Kokristalle Photolumineszenz Photophysik Zeitauflösende Spektroskopie 

摘      要：Singlet–triplet conversion in organic light‐emitting materials introduces non‐emissive (dark) and long‐lived triplet states, which represents a significant challenge in constraining the optical properties. There have been considerable attempts at separating singlets and triplets in long‐chain polymers, scavenging triplets, and quenching triplets with heavy metals; nonetheless, such triplet‐induced loss cannot be fully eliminated. Herein, a new strategy of crafting a periodic molecular barrier into the π‐conjugated matrices of organic aromatic fluorophores is reported. The molecular barriers effectively block the singlet‐to‐triplet pathway, resulting in near‐unity photoluminescence quantum efficiency (PLQE) of the organic fluorophores. The transient optical spectroscopy measurements confirm the absence of the triplet absorption. These studies provide a general approach to preventing the formation of dark triplet states in organic semiconductors and bring new opportunities for the development of advanced organic optics and photonics.