In order to improve the efficiency and stability of inverted three-dimensional(3D) or quasi-2D perovskite solar cells(PSCs) for future commercialization, exploring high efficient dopant-free polymer holetransporting m...In order to improve the efficiency and stability of inverted three-dimensional(3D) or quasi-2D perovskite solar cells(PSCs) for future commercialization, exploring high efficient dopant-free polymer holetransporting materials(HTMs) is still desired and meaningful. One simple and efficient way to achieve high performance dopant-free HTMs is to synthesize novel non-conjugated side-chain polymers via rational molecular design. In this work, N-(4-methoxyphenyl)-9,9-dimethyl-9H-fluoren-2-amine(FMeNPh) groups are introduced into the poly(N-vinylcarbazole)(PVK) side chains to afford two nonconjugated polymers PVCz-DFMeNPh and PVCz-FMeNPh as dopant-free HTMs in inverted quasi-2D PSCs. Benefited from the flexible properties of polyethylene backbone and excellent optoelectronic natures of FMeNPh side-chain groups, PVCz-DFMeNPh with more FMeNPh units exhibited excellent thermal stability, well-matched energy levels and improved charge mobility as compared to PTAA and PVCzFMeNPh. Moreover, the morphologies investigation of quasi-2D perovskite on PVCz-DFMeNPh shows more compact and homogeneous perovskite films than those on PTAA and PVCz-FMeNPh. As a result,the dopant-free PVCz-DFMeNPh based inverted quasi-2D PSCs deliver power conversion efficiency(PCE) up to 18.44% as well as negligible hysteresis and favorable long-term stability, which represents as excellent performance reported to date for inverted quasi-2D PSCs. The results demonstrate the great potentials of constructing non-conjugated side-chain polymer HTMs based on phenylfluorenamine-func tionalized PVK for the development of high efficient and stable inverted 3D or quasi-2D PSCs.展开更多
π-Electron coupling of pendant conjugated segment inπ-stacked semiconducting polymers always causes the formation of defect trapped sites and further quenched high-band excitons,which is harmful to the performance a...π-Electron coupling of pendant conjugated segment inπ-stacked semiconducting polymers always causes the formation of defect trapped sites and further quenched high-band excitons,which is harmful to the performance and stability of deep-blue polymer light-emitting diodes(PLEDs).Herein,considerate of“defect”carbazole(Cz)electromers in poly(N-vinylcarbazole)(PVK),a series of fluorene units are introduced into pendant segments(PVCz-DMeF,PVCz-FMeNPh and PVCz-DFMeNPh)to suppress the strongπ-electron coupling of pendant Cz units and enhance radiative transition toward fabricating sable PLEDs.Compared to PVCz-FMeNPh and PVCz-DFMeNPh,PVCz-DMeF spin-coated films show a relatively efficient deep-blue emission,completely similar to its single pendant chromophore,confirmed an extremely weak charge-transfer and electron coupling between adjacent pendant segments.Therefore,PLEDs based on PVCz-DMeF present stable and deep-blue emission with a high color purity(0.17,0.08),associated with extremely weak defect emission at 600∼700nm(induced by carbazole electromers).Finally,PLEDs based on PVCz-DMeF/F8BT blended films(1:1)also present the high maximum luminance(Lmax)of 6261 cd/m2 and current efficiency(CE_(max))of 2.03 cd/A,confirmed slightly trapped sites formation.Therefore,precisely control the arrangement and packing model of pendant units inπ-stacked polymer is an essential prerequisite for building efficient and stable emitter for optoelectronic devices.展开更多
In the design of conjugated molecules,modular production enables materials to easily realize structure modification and precisely tune their photoelectrical property.Construction of a novel and universal building bloc...In the design of conjugated molecules,modular production enables materials to easily realize structure modification and precisely tune their photoelectrical property.Construction of a novel and universal building block is crucial to design and manufacture high performance and stable conjugated molecules for optoelectronic application.Herein,we originally demonstrated a universal 4-qualifiable fluorene-based building block,which is a fundamental molecular segment to functionalize and obtain novel conjugated materials.Compared to the traditional modification at 9-site,additional 4-position functionalization provided an exciting blueprint to not only tune electronic structure and excited state via p-n molecular design engineering and space charge-transfer strategy,but also allow for optimizing intermolecular arrangement and obtaining solution-processing ability.The introduction of the 4-site substituent in fluorene based semiconductors may endow materials with unique properties.Finally,we successfully prepared two stable deep-blue light-emitting conjugated polymer,PODOPF and PODOF,by utilizing the 4-substituent fluorene based building block.It is believable that the performance,stability and processibility of reported outstanding fluorene-based conjugated molecules can be further optimized based on this universal building block.展开更多
Film morphology of emissive layers is crucial to the performance and stability of solution-processable organic light-emitting diodes(OLEDs). Compared to the interpenetration of conjugated polymer chain,small molecular...Film morphology of emissive layers is crucial to the performance and stability of solution-processable organic light-emitting diodes(OLEDs). Compared to the interpenetration of conjugated polymer chain,small molecular emitter with a flexible side chain always presents easily aggregation upon external treatment, and caused π-electronic coupling, which is undesirable for the efficiency and stability of deep-blue OLEDs. Herein, we proposed a side-chain coupling strategy to enhance the film morphological an emission stability of solution-processable small molecular deep-blue emitter. In contrary to “parent” MC8 TPA,the crosslinkable styryl and vinyl units were introduced as ended unit at the side-chain of Cm TPA and OEYTPA. Interestingly, Cm TPA and OEYTPA films present a relatively stable morphology and uniform deep-blue emission after thermal annealing(160 ℃) in the atmosphere, different to the discontinuous MC8 TPA annealed film. Besides, compared to the Cm TPA and OEYTPA ones, serious polaron formation in the MC8 TPA annealed film also negative to the deep-blue emission, according to transient absorption analysis. Therefore, both Cm TPA and OEYTPA annealed film obtained at 140 ℃ present an excellent deep-blue ASE behavior with a 445 nm, but absence for MC8 TPA ones, associated with the disruption of annealed films. Finally, enhancement of device performance based on Cm TPA and OEYTPA film(~40%)after thermal annealing with a similar performance curves also confirmed the assumption above. Therefore, these results also supported the effectiveness of our side-chain coupling strategy for optoelectronic applications.展开更多
The rational molecular design of light-emitting conjugated polymers that inherently suppress the ubiquitous coffee-ring effect(CRE)is a great challenge and the critical bottleneck for printing displays.Herein,we descr...The rational molecular design of light-emitting conjugated polymers that inherently suppress the ubiquitous coffee-ring effect(CRE)is a great challenge and the critical bottleneck for printing displays.Herein,we describe a supramolecular route to construct an intrinsically viscoelastic rigid conjugated polymer(RCP)(PHDPF-Cz)toward avoiding the CRE without sacrificing optoelectronic properties.Theπ-πstacking interactions derived fromthe pendant carbazole(Cz)units enable PHDPF-Cz to self-assemble into criss-cross nanofibers and endow its solutionwith great viscosity.Consequently,a high-quality and continuous PHDPFCz film was obtained by impeding the transport of aggregates to the droplet edge due to outward capillary flow during evaporation,in sharp contrast to the random aggregate migration and rapid precipitation generated fromthe controlled poly[4-(6-(9H-diphenylaniline-9-yl)hexyloxy)-9,9-diphenylfluorene]-co-[5-(6-(9H-diphenylaniline-9-yl)hexyloxy)-9,9-diphenylfluorene]and poly(9,9-dioctylfluorene)solutions.Finally,an efficient random laser is also achieved based on these cross-linked films with ultrastable single-chain excitonic behavior,confirming the effectiveness of our design strategy.展开更多
基金financially supported by the National Key Research and Development Program of China (2018YFB0406704)the National Natural Science Foundation of China (61974066, 61725502, 61634001)+3 种基金the Major Research Plan of the National Natural Science Foundation of China (91733302)the fund for Talented of Nanjing Tech University (201983)the Major Program of Natural Science Research of Jiangsu Higher Education Institutions of China (18KJA510002)the Synergetic Innovation Center for Organic Electronics and Information Displays。
文摘In order to improve the efficiency and stability of inverted three-dimensional(3D) or quasi-2D perovskite solar cells(PSCs) for future commercialization, exploring high efficient dopant-free polymer holetransporting materials(HTMs) is still desired and meaningful. One simple and efficient way to achieve high performance dopant-free HTMs is to synthesize novel non-conjugated side-chain polymers via rational molecular design. In this work, N-(4-methoxyphenyl)-9,9-dimethyl-9H-fluoren-2-amine(FMeNPh) groups are introduced into the poly(N-vinylcarbazole)(PVK) side chains to afford two nonconjugated polymers PVCz-DFMeNPh and PVCz-FMeNPh as dopant-free HTMs in inverted quasi-2D PSCs. Benefited from the flexible properties of polyethylene backbone and excellent optoelectronic natures of FMeNPh side-chain groups, PVCz-DFMeNPh with more FMeNPh units exhibited excellent thermal stability, well-matched energy levels and improved charge mobility as compared to PTAA and PVCzFMeNPh. Moreover, the morphologies investigation of quasi-2D perovskite on PVCz-DFMeNPh shows more compact and homogeneous perovskite films than those on PTAA and PVCz-FMeNPh. As a result,the dopant-free PVCz-DFMeNPh based inverted quasi-2D PSCs deliver power conversion efficiency(PCE) up to 18.44% as well as negligible hysteresis and favorable long-term stability, which represents as excellent performance reported to date for inverted quasi-2D PSCs. The results demonstrate the great potentials of constructing non-conjugated side-chain polymer HTMs based on phenylfluorenamine-func tionalized PVK for the development of high efficient and stable inverted 3D or quasi-2D PSCs.
基金supported by the National Natural Science Foundation of China(Nos.22105099 and 61874053)Natural Science Foundation of Jiangsu Province(No.BK20200700)+2 种基金the China Postdoctoral Science Foundation(No.2022M711591)the open research fund from Anhui Province Key Laboratory of Optoelectronic Materials Science and Technology(No.OMST202101)the State Key Laboratory of Luminescent Materials and Devices(South China University of Technology).
文摘π-Electron coupling of pendant conjugated segment inπ-stacked semiconducting polymers always causes the formation of defect trapped sites and further quenched high-band excitons,which is harmful to the performance and stability of deep-blue polymer light-emitting diodes(PLEDs).Herein,considerate of“defect”carbazole(Cz)electromers in poly(N-vinylcarbazole)(PVK),a series of fluorene units are introduced into pendant segments(PVCz-DMeF,PVCz-FMeNPh and PVCz-DFMeNPh)to suppress the strongπ-electron coupling of pendant Cz units and enhance radiative transition toward fabricating sable PLEDs.Compared to PVCz-FMeNPh and PVCz-DFMeNPh,PVCz-DMeF spin-coated films show a relatively efficient deep-blue emission,completely similar to its single pendant chromophore,confirmed an extremely weak charge-transfer and electron coupling between adjacent pendant segments.Therefore,PLEDs based on PVCz-DMeF present stable and deep-blue emission with a high color purity(0.17,0.08),associated with extremely weak defect emission at 600∼700nm(induced by carbazole electromers).Finally,PLEDs based on PVCz-DMeF/F8BT blended films(1:1)also present the high maximum luminance(Lmax)of 6261 cd/m2 and current efficiency(CE_(max))of 2.03 cd/A,confirmed slightly trapped sites formation.Therefore,precisely control the arrangement and packing model of pendant units inπ-stacked polymer is an essential prerequisite for building efficient and stable emitter for optoelectronic devices.
基金supported by the Natural Science Foundation of Jiangsu Province(No.BK20200700)National Natural Science Foundation of China(Nos.22075136,61874053)+4 种基金Natural Science Funds of the Education Committee of Jiangsu Province(No.18KJA430009)"High-Level Talents in Six Industries"of Jiangsu Province(No.XYDXX-019)Postgraduate Research&Practice Innovation Program of Jiangsu Province(Nos.KYCX21_1097,KYCX21_0771)Nanjing Vocational University of Industry Technology Start-up Fund(No.YK21-02-07)the open research fund from Anhui Province Key Laboratory of Environment-friendly Polymer Materials and Anhui Province Key Laboratory of Optoelectronic Materials Science and Technology.
文摘In the design of conjugated molecules,modular production enables materials to easily realize structure modification and precisely tune their photoelectrical property.Construction of a novel and universal building block is crucial to design and manufacture high performance and stable conjugated molecules for optoelectronic application.Herein,we originally demonstrated a universal 4-qualifiable fluorene-based building block,which is a fundamental molecular segment to functionalize and obtain novel conjugated materials.Compared to the traditional modification at 9-site,additional 4-position functionalization provided an exciting blueprint to not only tune electronic structure and excited state via p-n molecular design engineering and space charge-transfer strategy,but also allow for optimizing intermolecular arrangement and obtaining solution-processing ability.The introduction of the 4-site substituent in fluorene based semiconductors may endow materials with unique properties.Finally,we successfully prepared two stable deep-blue light-emitting conjugated polymer,PODOPF and PODOF,by utilizing the 4-substituent fluorene based building block.It is believable that the performance,stability and processibility of reported outstanding fluorene-based conjugated molecules can be further optimized based on this universal building block.
基金supported by the National Natural Science Foundation of China (Nos.22075136,61874053)National Key Research and Development Program of China (No.2020YFA0709900)+5 种基金Natural Science Funds of the Education Committee of Jiangsu Province (No.18KJA430009)Natural Science Foundation of Jiangsu Province (No.BK20200700)“High-Level Talents in Six Industries” of Jiangsu Province (No.XYDXX-019)Chain Postdoctoral Science Foundation (No.2021M692623)the open research fund from State Key Laboratory of Supramolecular Structure and Materials (No.sklssm202108)Anhui Province Key Laboratory of Environmentfriendly Polymer Materials and Anhui Province Key Laboratory of Optoelectronic Materials Science and Technology。
文摘Film morphology of emissive layers is crucial to the performance and stability of solution-processable organic light-emitting diodes(OLEDs). Compared to the interpenetration of conjugated polymer chain,small molecular emitter with a flexible side chain always presents easily aggregation upon external treatment, and caused π-electronic coupling, which is undesirable for the efficiency and stability of deep-blue OLEDs. Herein, we proposed a side-chain coupling strategy to enhance the film morphological an emission stability of solution-processable small molecular deep-blue emitter. In contrary to “parent” MC8 TPA,the crosslinkable styryl and vinyl units were introduced as ended unit at the side-chain of Cm TPA and OEYTPA. Interestingly, Cm TPA and OEYTPA films present a relatively stable morphology and uniform deep-blue emission after thermal annealing(160 ℃) in the atmosphere, different to the discontinuous MC8 TPA annealed film. Besides, compared to the Cm TPA and OEYTPA ones, serious polaron formation in the MC8 TPA annealed film also negative to the deep-blue emission, according to transient absorption analysis. Therefore, both Cm TPA and OEYTPA annealed film obtained at 140 ℃ present an excellent deep-blue ASE behavior with a 445 nm, but absence for MC8 TPA ones, associated with the disruption of annealed films. Finally, enhancement of device performance based on Cm TPA and OEYTPA film(~40%)after thermal annealing with a similar performance curves also confirmed the assumption above. Therefore, these results also supported the effectiveness of our side-chain coupling strategy for optoelectronic applications.
基金The work was supported by the National Natural Science Foundation of China(nos.22075136 and 61874053)National Key Research and Development Program of China(no.2020YFA0709900)+5 种基金Natural Science Funds of the Education Committee of Jiangsu Province(no.18KJA430009)Natural Science Foundation of Jiangsu Province(no.BK20200700)“High-Level Talents in Six Industries”of Jiangsu Province(no.XYDXX-019)China Postdoctoral Science Foundation(no.2021M692623)the Open Research Fund from State Key Laboratory of Supramolecular Structure and Materials(no.sklssm202108)Anhui Province Key Laboratory of Environment-friendly Polymer Materials and Anhui Province Key Laboratory of Optoelectronic Materials Science and Technology,Research Innovation in University of Jiangsu Province(nos.KYCX21_0771,KYCX21_0772,and KYCX21_1097).
文摘The rational molecular design of light-emitting conjugated polymers that inherently suppress the ubiquitous coffee-ring effect(CRE)is a great challenge and the critical bottleneck for printing displays.Herein,we describe a supramolecular route to construct an intrinsically viscoelastic rigid conjugated polymer(RCP)(PHDPF-Cz)toward avoiding the CRE without sacrificing optoelectronic properties.Theπ-πstacking interactions derived fromthe pendant carbazole(Cz)units enable PHDPF-Cz to self-assemble into criss-cross nanofibers and endow its solutionwith great viscosity.Consequently,a high-quality and continuous PHDPFCz film was obtained by impeding the transport of aggregates to the droplet edge due to outward capillary flow during evaporation,in sharp contrast to the random aggregate migration and rapid precipitation generated fromthe controlled poly[4-(6-(9H-diphenylaniline-9-yl)hexyloxy)-9,9-diphenylfluorene]-co-[5-(6-(9H-diphenylaniline-9-yl)hexyloxy)-9,9-diphenylfluorene]and poly(9,9-dioctylfluorene)solutions.Finally,an efficient random laser is also achieved based on these cross-linked films with ultrastable single-chain excitonic behavior,confirming the effectiveness of our design strategy.