Stability against oxygen is an important factor affecting the performance of organic semiconductor devices.Improving photooxidation stability can prolong the service life of the device and maintain the mechanical and ...Stability against oxygen is an important factor affecting the performance of organic semiconductor devices.Improving photooxidation stability can prolong the service life of the device and maintain the mechanical and photoelectric properties of the device.Generally,various encapsulation methods from molecular structure to macroscopic device level are used to improve photooxidation stability.Here,we adopted a crystallization strategy to allow 14H-spiro[dibenzo[c,h]acridine-7,9′-fluorene](SFDBA)to pack tightly to resist fluorescence decay caused by oxidation.In this case,the inert group of SFDBA acts as a“steric armor”,protecting the photosensitive group from being attacked by oxygen.Therefore,compared with the fluorescence quenching of SFDBA powder under 2 h of sunlight,SFDBA crystal can maintain its fluorescence emission for more than 8 h under the same conditions.Furthermore,the photoluminescence quantum yields(PLQYs)of the crystalline film is 327%higher than that of the amorphous film.It shows that the crystallization strategy is an effective method to resist oxidation.展开更多
Shape persistent conformations reduce the complexity of polymer materials. Herein, we propose a concept on the nanopolymer that is a nanoscale polymer chain with the repeat units of nanomonomers, In this article, a so...Shape persistent conformations reduce the complexity of polymer materials. Herein, we propose a concept on the nanopolymer that is a nanoscale polymer chain with the repeat units of nanomonomers, In this article, a soluble organic nanopolymer of wide bandgap semiconductors was synthesized by the Yamamoto polymerization of nanogrid monomer as the repeat units with the rectangle size of -1.7 nm × 1.2 nm. The alkyl side chain substituent at 9-position of fluorenes guarantees the polygrid with excellent solubility. Tetrafluorenes in the conjugation-interrupted backbones of polygrid acts as the active light-emitting centers without obvious green band in the fluorescence spectra of the films after 10 h annealing at 180 ℃, indicating this nanopolymer exhibits excellent spectral stability. Such soluble nanopolymers will be the fifth- generation of macromolecular materials with a potential character of overall performance improvement.展开更多
Rare attention has been paid to the comparison between a monomer and its corresponding polymer in terms of the optoelectronic characteristics. In this article, a model H-shaped molecule and its corresponding polymer, ...Rare attention has been paid to the comparison between a monomer and its corresponding polymer in terms of the optoelectronic characteristics. In this article, a model H-shaped molecule and its corresponding polymer, both of which exhibited similar properties including blue emission and solution processing, were designed and synthesized. Optoelectronic properties and various kinds of stability features, including the thermostabilities, spectral stabilities and amplified spontaneous emission characteristic of the monomer and polymer were investigated. In general, the corresponding polymer PH exhibited similar optoelectronic properties but deteriorated stabilities compared with its H-shaped monomer H-1 probably owing to the similar chemical structure but the wider molecular weight distribution and metal catalyst residue. Importantly, monomer H-1 displayed a comparable ASE threshold value with its polymer PH,suggesting that H-shaped fluorene-based small molecules may be more promising optical gain media in solid state amplifers and lasers.展开更多
基金supported by the Natural Science Foundation of Nanjing University of Posts and Telecommunications(NY222157,NY221085)State Key Laboratory of Organic Electronics and Information Display(GZR2022010008)+5 种基金Key Laboratory of Low-dimensional Materials Chemistry of Jiangsu Province(JSKC20022)General Program of China Postdoctoral Science Foundation(2022M711684)General Program of Basic Science(Natural Science)of Colleges and Universities of Jiangsu Province(22KJB430036)National Overseas Study Fund(202008320051)National Key Laboratory(2009DS690095)the National Natural Science Foundation of China(62288102).
文摘Stability against oxygen is an important factor affecting the performance of organic semiconductor devices.Improving photooxidation stability can prolong the service life of the device and maintain the mechanical and photoelectric properties of the device.Generally,various encapsulation methods from molecular structure to macroscopic device level are used to improve photooxidation stability.Here,we adopted a crystallization strategy to allow 14H-spiro[dibenzo[c,h]acridine-7,9′-fluorene](SFDBA)to pack tightly to resist fluorescence decay caused by oxidation.In this case,the inert group of SFDBA acts as a“steric armor”,protecting the photosensitive group from being attacked by oxygen.Therefore,compared with the fluorescence quenching of SFDBA powder under 2 h of sunlight,SFDBA crystal can maintain its fluorescence emission for more than 8 h under the same conditions.Furthermore,the photoluminescence quantum yields(PLQYs)of the crystalline film is 327%higher than that of the amorphous film.It shows that the crystallization strategy is an effective method to resist oxidation.
基金partially financially supported by the National Natural Science Funds for Excellent Young Scholar(No.21322402)the National Natural Science Foundation of China(Nos.21274064,21504041,21504047 and 61136003)+4 种基金Excellent Science and Technology Innovation Team of Jiangsu Higher Education Institutions(2013)Synergetic Innovation Center for Organic Electronics and Information Displays,the Natural Science Foundation of Jiangsu Province(Nos.BK20150834 and BM2012010)Open Project from State Key Laboratory of Supramolecular Structure and Materials at Jilin University(No.klssm201612)Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Nanjing University of Posts and Telecommunications Scientific Foundation(NUPTSF)(No.NY214179)
文摘Shape persistent conformations reduce the complexity of polymer materials. Herein, we propose a concept on the nanopolymer that is a nanoscale polymer chain with the repeat units of nanomonomers, In this article, a soluble organic nanopolymer of wide bandgap semiconductors was synthesized by the Yamamoto polymerization of nanogrid monomer as the repeat units with the rectangle size of -1.7 nm × 1.2 nm. The alkyl side chain substituent at 9-position of fluorenes guarantees the polygrid with excellent solubility. Tetrafluorenes in the conjugation-interrupted backbones of polygrid acts as the active light-emitting centers without obvious green band in the fluorescence spectra of the films after 10 h annealing at 180 ℃, indicating this nanopolymer exhibits excellent spectral stability. Such soluble nanopolymers will be the fifth- generation of macromolecular materials with a potential character of overall performance improvement.
基金financially supported by the National Natural Science Foundation of China (Nos. 21504047, 21774061)the Six Peak Talents Foundation of Jiangsu Province (No. XCL-CXTD009)+1 种基金Natural Science Foundation of Jiangsu Province (No. BK20150834)Synergetic Innovation Center for Organic Electronics and Information Displays
文摘Rare attention has been paid to the comparison between a monomer and its corresponding polymer in terms of the optoelectronic characteristics. In this article, a model H-shaped molecule and its corresponding polymer, both of which exhibited similar properties including blue emission and solution processing, were designed and synthesized. Optoelectronic properties and various kinds of stability features, including the thermostabilities, spectral stabilities and amplified spontaneous emission characteristic of the monomer and polymer were investigated. In general, the corresponding polymer PH exhibited similar optoelectronic properties but deteriorated stabilities compared with its H-shaped monomer H-1 probably owing to the similar chemical structure but the wider molecular weight distribution and metal catalyst residue. Importantly, monomer H-1 displayed a comparable ASE threshold value with its polymer PH,suggesting that H-shaped fluorene-based small molecules may be more promising optical gain media in solid state amplifers and lasers.
