Solid‐State Fluorophores with Combined Excited‐State Intramolecular Proton Transfer‐Aggregation‐Induced Emission as Efficient Emitters for Electroluminescent Devices

Advanced Photonics Research

Nawee Kungwan¹  Chattarika Sukpattanacharoen¹  Chaiyon Chaiwai²  Taweesak Sudyoadsuk²  Thanyarat Chawanpunyawat²  Pongsakorn Chasing²  Jakkapan Kumsampao²  Phattananawee Nalaoh²  Vinich Promarak²  Supawadee Namuangruk³ 

[1] Department of Chemistry Faculty of Science Chiang Mai University Muang District Chiang Mai 50200 Thailand;Department of Materials Science and Engineering School of Molecular Science and Engineering Vidyasirimedhi Institute of Science and Technology Wangchan Rayong 21210 Thailand;National Nanotechnology Center National Science and Technology Development Agency Klong Luang Pathumthani 12120 Thailand;

关键词: aggregation-induced emission;    electroluminescent devices;    excited-state intramolecular proton transfer;    self-absorption free;    solid-state fluorophores;   

DOI  :  10.1002/adpr.202100141

来源: DOAJ

【 摘 要 】

A series of excited‐state intramolecular proton transfer (ESIPT)–aggregate‐induced emission (AIE) solid‐state fluorophores (TTHPI, PTHPI, and ATHPI) are reported as self‐absorption‐free emitters for electroluminescent (EL) devices. The molecules contain 2‐(2‐hydroxyphenyl)‐1,4,5‐triphenylimidazole as an ESIPT core being double functionalized with AIE‐active luminogen of tetraphenylethene and hole‐transporting moiety (triphenylamine, N‐(4‐phenyl)phenoxazine, or N‐(4‐phenyl)‐9,9‐dimethylacridine) to improve their solid‐state emission due to the AIE effect and hole‐transporting capability. The ESIPT, AIE, and photophysical properties are theoretically and experimentally studied. All molecules demonstrate ESIPT and AIE characters with intense sky‐blue/green color emissions from a pure keto‐form emission in the solid‐state and photoluminescence quantum yields of 41–74%. These ESIPT–AIE fluorophores exhibit high thermal and electrochemical stabilities with decent hole mobilities and are successfully utilized as emitters in organic light‐emitting diodes (OLEDs). All devices show pure keto‐form EL emissions with moderate‐to‐good EL performances. Particularly, the TTHPI‐based device achieves excellent EL performance with a maximum external quantum efficiency (EQEmax) of 5.21%, a maximum current efficiency (CEmax) of 11.17 cd A−1, and a slight efficiency roll‐off.

【 授权许可】

Unknown