{"title":"Pure Organic Thermally Activated Delayed Fluorescence Afterglow Polymers via Dopant Isomerization.","authors":"Guanyu Liu, Zixin Yan, Qi Song, Qikun Sun, Shanfeng Xue, Wenjun Yang","doi":"10.1021/acsmacrolett.4c00818","DOIUrl":null,"url":null,"abstract":"<p><p><i>N</i>-(<i>o</i>-Cyanophenyl)carbazole can be dimerized at different positions, which may change excited state behaviors. Herein, 2,3'-dicyano-3,4'-di(carbazol-9-yl)biphenyl (D34C) is designed and synthesized and doped into polymers. However, we find that D34C does not exhibit room temperature phosphorescence but emits fluorescence (FL) and bright thermally activated delayed fluorescence (TADF) with lifetimes of hundreds of milliseconds, which is observed in diverse matrices such as PMMA, MBS, ABS, PS, HIPS, and SIS. The simple positional isomerization makes the abundant triplet excitons undergo only reverse intersystem crossing rather than room temperature phosphorescence (RTP) radiation, which is rather rare in organic doped polymers. Since the production of TADF afterglow requires a certain excitation time, the generally indistinguishable FL and TADF efficiencies are separated for the first time. This work not only provides novel TADF afterglow polymers with diverse mechanical properties but also will evoke the subtle design of conjugated organic molecules to dramatically change photoexcitation and emission behaviors.</p>","PeriodicalId":18,"journal":{"name":"ACS Macro Letters","volume":" ","pages":"265-271"},"PeriodicalIF":5.1000,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Macro Letters","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/acsmacrolett.4c00818","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
N-(o-Cyanophenyl)carbazole can be dimerized at different positions, which may change excited state behaviors. Herein, 2,3'-dicyano-3,4'-di(carbazol-9-yl)biphenyl (D34C) is designed and synthesized and doped into polymers. However, we find that D34C does not exhibit room temperature phosphorescence but emits fluorescence (FL) and bright thermally activated delayed fluorescence (TADF) with lifetimes of hundreds of milliseconds, which is observed in diverse matrices such as PMMA, MBS, ABS, PS, HIPS, and SIS. The simple positional isomerization makes the abundant triplet excitons undergo only reverse intersystem crossing rather than room temperature phosphorescence (RTP) radiation, which is rather rare in organic doped polymers. Since the production of TADF afterglow requires a certain excitation time, the generally indistinguishable FL and TADF efficiencies are separated for the first time. This work not only provides novel TADF afterglow polymers with diverse mechanical properties but also will evoke the subtle design of conjugated organic molecules to dramatically change photoexcitation and emission behaviors.
期刊介绍:
ACS Macro Letters publishes research in all areas of contemporary soft matter science in which macromolecules play a key role, including nanotechnology, self-assembly, supramolecular chemistry, biomaterials, energy generation and storage, and renewable/sustainable materials. Submissions to ACS Macro Letters should justify clearly the rapid disclosure of the key elements of the study. The scope of the journal includes high-impact research of broad interest in all areas of polymer science and engineering, including cross-disciplinary research that interfaces with polymer science.
With the launch of ACS Macro Letters, all Communications that were formerly published in Macromolecules and Biomacromolecules will be published as Letters in ACS Macro Letters.