Efficient room temperature phosphorescence (RTP) is rarely observed in pure organic luminogens. However, we have newly observed that benzil and its derivatives are nonluminescent in solvents and thin layer chromatogra...Efficient room temperature phosphorescence (RTP) is rarely observed in pure organic luminogens. However, we have newly observed that benzil and its derivatives are nonluminescent in solvents and thin layer chromatography (TLC) plates, but become highly phosphorescent in crystal state at room temperature, exhibiting typical crystallization-induced phosphorescence (CIP) characteristics. The CIP phenomenon is ascribed to the restriction of intramolecular rotations in crystals owing to effective intermolecular interactions. Such intermolecular interactions greatly rigidify the molecular conformation and significantly decrease the nonradiative deactivation channels of the triplet excitons, thus giving boosted phosphorescent emission at room temperature.展开更多
Fluorescence imaging can be employed in fields of medical treatment,astronomical exploration,and national defense security.Traditional fluorescence imaging often takes the single-photon techniques,which is vulnerable ...Fluorescence imaging can be employed in fields of medical treatment,astronomical exploration,and national defense security.Traditional fluorescence imaging often takes the single-photon techniques,which is vulnerable to background interference and photobleaching.Remedially,two-photon fluorescence imaging can achieve much higher-resolution fluorescence imaging for reducing scattering and deeper depth.Hence,by assembling the tetraphenylethylene backbones with nontoxic and non-noble K^(+)ions,compound 1([(Hdma)K(H_(2)ettc)]_(n),H_(4)ettc=4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'-biphenyl]-4-carboxylic acid)))with the crystallization-induced emissions exhibited charming fluorescence imaging under two-photon excitation microscopy(TPEM).Besides,luminescent powders based on compound 1 can achieve high-resolution fingerprint recognition,providing secure access control and identification for a novel authentication method.Compared with the commercial fluorescent dyes coumarin-6,the as-synthesized compound 1 showed great solvent stability,indicating its durability against harsh environment.Moreover,compound 1 shows mechanoluminescent properties for the perturbation of weak supramolecular interactions within ordered arrangements of the H_(2)ettc^(2−)ligands.This novel compound has provided an important insight to the development of twophoton fluorescence imaging and advanced external-stimuli responsive materials.展开更多
This review summarizes the recent progress of efficient room temperature phosphorescence(RTP) from pure organic luminogens achieved by crystallization-induced phosphorescence(CIP),with focus on the advances in our...This review summarizes the recent progress of efficient room temperature phosphorescence(RTP) from pure organic luminogens achieved by crystallization-induced phosphorescence(CIP),with focus on the advances in our group.Besides homocrystals,mixed crystals and cocrystals are also discussed.Meanwhile,intriguing RTP emission from the luminogens without conventional chromophores is demonstrated.展开更多
Pure organic luminogens with efficient room temperature phosphorescence(RTP) and remarkable mechanochromism are highly desired in view of their fundamental significance and technical applications. Herein, four twist...Pure organic luminogens with efficient room temperature phosphorescence(RTP) and remarkable mechanochromism are highly desired in view of their fundamental significance and technical applications. Herein, four twisted pure organic luminogens based on benzophenone and aromatic amines were synthesized and their photophysical properties were thoroughly investigated. They exhibit crystallization-induced phosphorescence(CIP), giving bright fluorescence and phosphorescence dual emission in crystals. Upon grinding, they become amorphous and emit predominantly red-shifted fluorescence, demonstrating remarkable mechanochromism. Furthermore, three of them even demonstrate greatly enhanced emission upon grinding, which is rarely observed in twisted D-A structured luminogens.展开更多
The manipulation of the morphology of the active layers is crucial for improving the performance of organic photovoltaic(OPV)devices. In particular, the development of non-fullerene acceptors(NFAs) has led to a large ...The manipulation of the morphology of the active layers is crucial for improving the performance of organic photovoltaic(OPV)devices. In particular, the development of non-fullerene acceptors(NFAs) has led to a large number of new materials with more complex interactions. Therefore, the investigation on the morphology control mechanism is the key aspect in providing guidance for material design and device optimization. In this study, the film morphology optimization using 1,8-diiodooctane(DIO) additive and a ternary fullerene acceptor strategy have been carried out based on the PCE10:ITIC blends. It is seen that suitable amount of DIO helps to increase the crystallization of the blended thin film. However, excessive DIO elevates the crystallization-induced phase separation and the domain size can exceed the exciton diffusion length, leading to efficiency drop. The addition of fullerene acceptor can improve the carrier transport of the blends, and its presence could retard the excessive phase separation induced by DIO additive. Under the joint optimization of the solvent additive and PCBM acceptor,the film morphology achieves a balance between crystallization and phase separation scales, the exciton diffusion and carrier transport are also optimized, and the short-circuit current(JSC) and fill factor(FF) of the device can be improved significantly.展开更多
Organic micro/nanocrystals with polymorphic tailorability and perfect platform to modulate decode the complex relationship among molecular structures,supramolecular/noncovalent interactions,aggregates and exciton beha...Organic micro/nanocrystals with polymorphic tailorability and perfect platform to modulate decode the complex relationship among molecular structures,supramolecular/noncovalent interactions,aggregates and exciton behaviors.Herein,we precisely tune the polymorphic two-dimensional organic nanosheets(2DONs)of cyano-spirocyclic aromatic hydrocarbon(2'-CN-SFX),where the crystal growth processes are dominated by precursor concentration.The low concentration(ca.2 mmol/L)affords the rhombus-like nanosheets with monoclinic P21/c space group,in which molecules adopt antiparallel and slipped stacking mode.In contrast,the high concentration(ca.4 mmol/L)favors herringbone-like molecular packing pattern and then generates shuttle-like nanosheets with monoclinic C2/c space group.Both above polymorphic nanosheets exhibit unprecedented crystallization-induced emission en-hancement(CIEE)feature that increases the photoluminescence quantum yields(PLQYs)from 16%in solution,21%in amorphous film to 37%-39%in crystalline states.This result will offer promising opportunities for nanophotonics and organic intelligent semi-conductors.展开更多
The development of fluorescent nanocrystals based on organic small molecules is of great importance in bioimaging due to the merits of easy modification,high brightness and excellent photostability,however suffering f...The development of fluorescent nanocrystals based on organic small molecules is of great importance in bioimaging due to the merits of easy modification,high brightness and excellent photostability,however suffering from the emission-detrimental aggregation-caused quenching(ACQ)effect.Herein,we successfully designed and synthesized an AIE-active di(N,N-dimethylaniline)-dibenzofulvene(named as NFTPE),which exhibits the crystallization-induced emission enhancement(CIEE)effect.Interestingly,two types of yellow-and orange-emissive crystals for NFTPE were obtained,exhibiting aggregation microenvironment-dependent emission tuning in the solid state.Single-crystal analysis and density functional theory(DFT)calculations reveal that different aggregation microenvironments result in the distinct molecular conformation for various emission.Excitingly,the crystallization of NFTPE in an aqueous solution under the assistance of amphiphilic PEG polymer matrices could be monitored in situ by the fluorescence changes,facilitating the preparation of NFTPE nanocrystals(NFTPE-NCs)by adjusting the aggregation microenvironment.The obtained NFTPE-NCs exhibit the superior performance in cell imaging in respect to high brightness,photostability,and biocompatibility,thus demonstrating the potential in bioimaging applications.展开更多
Two derivatives of tetraphenylethene (TPE) were synthesized through one step cross McMurry coupling reaction. Both luminogens exhibit aggregation-induced emission (AIE) and crystallization induced emission enhancement...Two derivatives of tetraphenylethene (TPE) were synthesized through one step cross McMurry coupling reaction. Both luminogens exhibit aggregation-induced emission (AIE) and crystallization induced emission enhancement (CIEE). The emissions of both luminogens could be switched between blue and green through reversible modulation of morphology with thermal, organic solvent fuming and mechanical stimuli. Thus we provide a possible design strategy for emission switching materials.展开更多
基金the National Natural Science Foundations of China (21104044)the National Basic Research Program of China (973 Program, 2013CB834701 and 2013CB834704)+1 种基金the Ph.D. Programs Foundation of Ministry of Education of China (20110073120040)the Shanghai Leading Academic Discipline Project (B202). W.Z.Y. thanks the Start-up Foundation and SMC-Chenxing Young Scholar Pro- gram of Shanghai Jiao Tong University.
文摘Efficient room temperature phosphorescence (RTP) is rarely observed in pure organic luminogens. However, we have newly observed that benzil and its derivatives are nonluminescent in solvents and thin layer chromatography (TLC) plates, but become highly phosphorescent in crystal state at room temperature, exhibiting typical crystallization-induced phosphorescence (CIP) characteristics. The CIP phenomenon is ascribed to the restriction of intramolecular rotations in crystals owing to effective intermolecular interactions. Such intermolecular interactions greatly rigidify the molecular conformation and significantly decrease the nonradiative deactivation channels of the triplet excitons, thus giving boosted phosphorescent emission at room temperature.
基金supported by the National Natural Science Foundation of China(Nos.22205237,22271283,21971240,and 21827813)the National Key Research and Development Program of China(No.2017YFA0206802)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(No.YJKYYQ20210039).
文摘Fluorescence imaging can be employed in fields of medical treatment,astronomical exploration,and national defense security.Traditional fluorescence imaging often takes the single-photon techniques,which is vulnerable to background interference and photobleaching.Remedially,two-photon fluorescence imaging can achieve much higher-resolution fluorescence imaging for reducing scattering and deeper depth.Hence,by assembling the tetraphenylethylene backbones with nontoxic and non-noble K^(+)ions,compound 1([(Hdma)K(H_(2)ettc)]_(n),H_(4)ettc=4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'-biphenyl]-4-carboxylic acid)))with the crystallization-induced emissions exhibited charming fluorescence imaging under two-photon excitation microscopy(TPEM).Besides,luminescent powders based on compound 1 can achieve high-resolution fingerprint recognition,providing secure access control and identification for a novel authentication method.Compared with the commercial fluorescent dyes coumarin-6,the as-synthesized compound 1 showed great solvent stability,indicating its durability against harsh environment.Moreover,compound 1 shows mechanoluminescent properties for the perturbation of weak supramolecular interactions within ordered arrangements of the H_(2)ettc^(2−)ligands.This novel compound has provided an important insight to the development of twophoton fluorescence imaging and advanced external-stimuli responsive materials.
基金financially supported by the National Natural Science Foundation of China(No.51473092)the Shanghai Rising-Star Program(No.15QA1402500)the SMC-Chenxing Young Scholar Program of Shanghai Jiao Tong University
文摘This review summarizes the recent progress of efficient room temperature phosphorescence(RTP) from pure organic luminogens achieved by crystallization-induced phosphorescence(CIP),with focus on the advances in our group.Besides homocrystals,mixed crystals and cocrystals are also discussed.Meanwhile,intriguing RTP emission from the luminogens without conventional chromophores is demonstrated.
基金financially supported by the National Natural Science Foundation of China (No. 51473092)
文摘Pure organic luminogens with efficient room temperature phosphorescence(RTP) and remarkable mechanochromism are highly desired in view of their fundamental significance and technical applications. Herein, four twisted pure organic luminogens based on benzophenone and aromatic amines were synthesized and their photophysical properties were thoroughly investigated. They exhibit crystallization-induced phosphorescence(CIP), giving bright fluorescence and phosphorescence dual emission in crystals. Upon grinding, they become amorphous and emit predominantly red-shifted fluorescence, demonstrating remarkable mechanochromism. Furthermore, three of them even demonstrate greatly enhanced emission upon grinding, which is rarely observed in twisted D-A structured luminogens.
基金financially supported by the National Natural Science Foundation of China (Nos.51973110,21734009,21905102 and 22109094)the National Key R&D Program of China (Nos.2020YFB1505500 and 2020YFB1505502)+3 种基金the Program of Shanghai Science and Technology Commission science and technology innovation action plan (Nos.20ZR1426200,20511103800,20511103802 and 20511103803)the Natural Science Foundation of Shandong Province (No.ZR2019LFG005)the Key research project of Shandong Province (No.2020CXGC010403)the Center of Hydrogen Science,Shanghai Jiao Tong University,China。
文摘The manipulation of the morphology of the active layers is crucial for improving the performance of organic photovoltaic(OPV)devices. In particular, the development of non-fullerene acceptors(NFAs) has led to a large number of new materials with more complex interactions. Therefore, the investigation on the morphology control mechanism is the key aspect in providing guidance for material design and device optimization. In this study, the film morphology optimization using 1,8-diiodooctane(DIO) additive and a ternary fullerene acceptor strategy have been carried out based on the PCE10:ITIC blends. It is seen that suitable amount of DIO helps to increase the crystallization of the blended thin film. However, excessive DIO elevates the crystallization-induced phase separation and the domain size can exceed the exciton diffusion length, leading to efficiency drop. The addition of fullerene acceptor can improve the carrier transport of the blends, and its presence could retard the excessive phase separation induced by DIO additive. Under the joint optimization of the solvent additive and PCBM acceptor,the film morphology achieves a balance between crystallization and phase separation scales, the exciton diffusion and carrier transport are also optimized, and the short-circuit current(JSC) and fill factor(FF) of the device can be improved significantly.
基金supported by the National Natural Science Foundation of China(Nos.61604081,61605090,U1301243)the Natural Science Foundation of the Jiangsu Higher Education Institutions(No.16KJB430023)+6 种基金the Doctoral Fund of Ministry of Education of China(No.20133223110007)the Excellent Science and Technology Innovation Team of Jiangsu Higher Education Institutions(2013)the Natural Science Foundation of jiangsu Province(No.BM2012010)the Six Talent Peaks Project of Jiangsu Province(No.XCL-CXTD-009)the Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,PAPD(No.YX03002)NUPTSF(Nos.NY215055,NY215061)the Program for Postgraduates Research Innovation in University of Jiangsu Province(No.KYCX200744)。
文摘Organic micro/nanocrystals with polymorphic tailorability and perfect platform to modulate decode the complex relationship among molecular structures,supramolecular/noncovalent interactions,aggregates and exciton behaviors.Herein,we precisely tune the polymorphic two-dimensional organic nanosheets(2DONs)of cyano-spirocyclic aromatic hydrocarbon(2'-CN-SFX),where the crystal growth processes are dominated by precursor concentration.The low concentration(ca.2 mmol/L)affords the rhombus-like nanosheets with monoclinic P21/c space group,in which molecules adopt antiparallel and slipped stacking mode.In contrast,the high concentration(ca.4 mmol/L)favors herringbone-like molecular packing pattern and then generates shuttle-like nanosheets with monoclinic C2/c space group.Both above polymorphic nanosheets exhibit unprecedented crystallization-induced emission en-hancement(CIEE)feature that increases the photoluminescence quantum yields(PLQYs)from 16%in solution,21%in amorphous film to 37%-39%in crystalline states.This result will offer promising opportunities for nanophotonics and organic intelligent semi-conductors.
基金This work was partially supported by the National Natural Science Foundation of China(Nos.21702016,21905015 and 52003023)the Fund of the Beijing National Laboratory for Molecular Sciences,China(No.BNLMS201813).B.Z.Tang acknowledges the financial support from the National Natural Science Foundation of China(No.21788102)+1 种基金the Research Grants Council of Hong Kong(Nos.N_HKUT609/19,16305518,and C6009-17G)the Innovation and Technology Commission(No.ITC-CNERC14SC01).
文摘The development of fluorescent nanocrystals based on organic small molecules is of great importance in bioimaging due to the merits of easy modification,high brightness and excellent photostability,however suffering from the emission-detrimental aggregation-caused quenching(ACQ)effect.Herein,we successfully designed and synthesized an AIE-active di(N,N-dimethylaniline)-dibenzofulvene(named as NFTPE),which exhibits the crystallization-induced emission enhancement(CIEE)effect.Interestingly,two types of yellow-and orange-emissive crystals for NFTPE were obtained,exhibiting aggregation microenvironment-dependent emission tuning in the solid state.Single-crystal analysis and density functional theory(DFT)calculations reveal that different aggregation microenvironments result in the distinct molecular conformation for various emission.Excitingly,the crystallization of NFTPE in an aqueous solution under the assistance of amphiphilic PEG polymer matrices could be monitored in situ by the fluorescence changes,facilitating the preparation of NFTPE nanocrystals(NFTPE-NCs)by adjusting the aggregation microenvironment.The obtained NFTPE-NCs exhibit the superior performance in cell imaging in respect to high brightness,photostability,and biocompatibility,thus demonstrating the potential in bioimaging applications.
基金partially supported by the National Natural Science Foundation of China(51173018)National Basic Research Program of China(2013CB834704,2011CB935702)+1 种基金the Fundamental Research Funds for the Central Universities,RPC Grants of HKUST(RPC11SC09)the Research Grants Council of Hong Kong(HKUST2/CRF/10)
文摘Two derivatives of tetraphenylethene (TPE) were synthesized through one step cross McMurry coupling reaction. Both luminogens exhibit aggregation-induced emission (AIE) and crystallization induced emission enhancement (CIEE). The emissions of both luminogens could be switched between blue and green through reversible modulation of morphology with thermal, organic solvent fuming and mechanical stimuli. Thus we provide a possible design strategy for emission switching materials.