Enhanced deep-red emission in donor-acceptor molecular architecture:The role of ancillary acceptor of cyanophenyl  

作　　者：Yue Shen Xiaohui Tang Yuwei Xu Haichao Liu Shitong Zhang Bing Yang Yuguang Ma 

机构地区：[1]State Key Laboratory of Supramolecular Structure and Materials,College of Chemistry,Jilin University,Changchun 130012,China [2]State Key Laboratory of Luminescent Materials and Devices,South China University of Technology,Guangzhou 510640,China

出　　处：《Chinese Chemical Letters》2019年第11期1947-1950,共4页中国化学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.91833304,51873077,51803071 and51673083);the National Basic Research Program of China(Nos.2015CB655003 and 2016YFB0401001);the Postdoctoral Innovation Talent Support Project(Nos.BX201700097 and BX20180121);the China Postdoctoral Science Foundation(Nos.2017M620108 and2018M641767);JLUSTIRT(No.2019TD-33)

摘　　要：Organic solid-state luminescent materials with high-efficiency deep-red emission have attracted considerable interest in recent years.Constructing donor-acceptor(D-A)type molecules has been one of most commonly used strategies to achieve deep-red emission,but it is always difficult to achieve high photoluminescence(PL)quantum yield(ηPL)due to forbidden charge-transfer state.Herein,we report a new D-A type molecule 4-(7-(4-(diphenylamino)phenyl)-9-oxo-9H-fluoren-2-yl)benzonitrile(TPAFOCN),deriving from donor-acceptor-donor(D-A-D)type 2,7-bis(4-(diphenylamino)phenyl)-9H-fluoren-9-one(DTPA-FO)with a fluorescence maximum of 627 nm in solids.This molecular design enables a transformation of acceptor from fluorenone(FO)itself to 4-(9-oxo-9H-fluoren-2-yl)benzonitrile(FOCN).Compared with DTPA-FO,the introduction of cyanophenyl not only shifts the emission of TPA-FOCN to deep red with a fluorescence maximum of 668 nm in solids,but also maintains the highηPL of 10%.Additionally,a solution-processed non-doped organic light-emitting diode(OLED)was fabricated with TPA-FOCN as emitter.TPA-FOCN device showed a maximum luminous efficiency of 0.13 cd/A and a maximum external quantum efficiency(EQE)of 0.22%with CIE coordinates of(0.64,0.35).This work provides a valuable strategy for the rational design of high-efficiency deep-red emission materials using cyanophenyl as an ancillary acceptor.Organic solid-state luminescent materials with high-efficiency deep-red emission have attracted considerable interest in recent years.Constructing donor-acceptor（D-A） type molecules has been one of most commonly used strategies to achieve deep-red emission,but it is always difficult to achieve high photoluminescence（PL） quantum yield(ηPL) due to forbidden charge-transfer state.Herein,we report a new D-A type molecule 4-（7-（4-（diphenylamino）phenyl）-9-oxo-9 H-fluoren-2-yl）benzonitrile（TPAFOCN）,deriving from donor-acceptor-donor（D-A-D） type 2,7-bis（4-（diphenylamino）phenyl）-9 Hfluoren-9-one（DTPA-FO） with a fluorescence maximum of 627 nm in solids.This molecular design enables a transformation of acceptor from fluorenone（FO） itself to 4-（9-oxo-9 H-fluoren-2-yl）benzonitrile（FOCN）.Compared with DTPA-FO,the introduction of cyanophenyl not only shifts the emission of TPA-FOCN to deep red with a fluorescence maximum of 668 nm in solids,but also maintains the high ηPL of 10%.Additionally,a solution-processed non-doped organic light-emitting diode（OLED）was fabricated with TPA-FOCN as emitter.TPA-FOCN device showed a maximum luminous efficiency of0.13 cd/A and a maximum external quantum efficiency（EQE） of 0.22% with CIE coordinates of（0.64,0.35）.This work provides a valuable strategy for the rational design of high-efficiency deep-red emission materials using cyanophenyl as an ancillary acceptor.

关 键 词：Deep-red emission FLUORENONE Cyanophenyl group DONOR-ACCEPTOR Organic light-emitting diodes 

分 类 号：O62[理学—有机化学]