The DCM dye doped organic electroluminescence devices with structure of ITO/NPB/Alq 3 : DCM/Alq 3 /LiF/Al were fabricated. From 15 K to room temperature, the magnetic field dependent of electroluminescence (MEL) of de...The DCM dye doped organic electroluminescence devices with structure of ITO/NPB/Alq 3 : DCM/Alq 3 /LiF/Al were fabricated. From 15 K to room temperature, the magnetic field dependent of electroluminescence (MEL) of devices was investigated. Our observations indicated that the MEL is composed of two effects in different regimes: a low field (0≤B≤40 mT) effect and a high field (B 】 40 mT) effect. For undoped devices, the low field effect exhibits a rapid rising with the increasing field, and the high field effect shows a slow increase and gradually saturates at room temperature. For doped devices, the low field rapid increase is also present, whereas the high field effect displays a decrease with the increasing field. The larger the injection current is, the more apparent the high field decrease is. In addition, the doped device demonstrates less temperature dependence of the high field effect than undoped device, although the undoped devices also present high field decrease of electroluminescence at low temperatures (T≤150 K). Based on the energy level trapping effect due to dye doping and magnetic field modulated triplet exciton annihilation, the experimental results are carefully explained.展开更多
Based on experimental data of positron annihilation technology, electrolyticdissolution technique, electron back-scattered pattern, etc. and by analysis the strengtheningfactors, the strengthening mechanism of ultra-t...Based on experimental data of positron annihilation technology, electrolyticdissolution technique, electron back-scattered pattern, etc. and by analysis the strengtheningfactors, the strengthening mechanism of ultra-thin hot strip of low carbon steel produced by CSP(Compact Strip Production) technique was investigated. The value of each strengthening mechanism andits contribution percentage to yield strength were achieved. The results show that refinementstrengthening is the predominant strengthening mode; precipitation strengthening and dislocationstrengthening are second to it, their contributions to yield strength are almost equal.展开更多
By means of an improved mapping method and a variable separation method, a series of variable separation solutions including solitary wave solutions, periodic wave solutions and rational function solutions） to the （...By means of an improved mapping method and a variable separation method, a series of variable separation solutions including solitary wave solutions, periodic wave solutions and rational function solutions） to the （2＋1）-dimensional breaking soliton system is derived. Based on the derived solitary wave excitation, we obtain some special annihilation solitons and chaotic solitons in this short note.展开更多
Studying the source of particle properties is the most important goal for scientists, so it was necessary to use the means available to us, which is physical logic to study these properties. In this paper, you will ex...Studying the source of particle properties is the most important goal for scientists, so it was necessary to use the means available to us, which is physical logic to study these properties. In this paper, you will examine how the type of coordinates in which electromagnetic fields are distributed can have a role in detecting particle properties, specifically using the Riemann-Silberstein vector. Because electromagnetism it deals with electric and magnetic fields together for any electromagnetic sentence, and when we study it according to multiple coordinates and study its derivation by changing coordinates, we discover how the electromagnetic sentences are transformed from one particle to another.展开更多
Room-temperature ferromagnetism is observed in the O^(+)-implanted AIN films with O+doses of 5×10^(16) cm^(-2)(AIN:Osxion)and 2×10^(17) cm^(-2)(AIN:O_(2x1on)).The observed magnetic anisotropy indicates that ...Room-temperature ferromagnetism is observed in the O^(+)-implanted AIN films with O+doses of 5×10^(16) cm^(-2)(AIN:Osxion)and 2×10^(17) cm^(-2)(AIN:O_(2x1on)).The observed magnetic anisotropy indicates that the ferromagnetism is attributed to the intrinsic properties of O^(+) -implanted AIN films.The out-of-plane saturation magnetization(Ms)of the AIN:O5×10^(16) is about 0.68 emu/g,much higher than that of AIN:O_(2x1017),0.09 emu/g,which is due to the excessively high O^(+)dose made more O+ions occupy adjacent A1^(3+)positions in forms of antiferromagnetic coupling.Doppler broadening of positron annihilation radiation measurements demonstrate the existence of Al vacancies in the O^(+)-implanted AIN films.The first-principles calculations suggest that the ferromagnetism originates mainly from the Al vacancies.Meanwhile,the formation of divacancies or vacancy clusters by high concentrations of Al vacancies will lead to the transformation of VA-VAi coupling from ferromagnetim to antiferromagnetism,ultimately weakening the ferromagnetism of the sample.展开更多
The modulation of circularly polarized luminescence(CPL) has become an increasingly prominent area of research. In this study,we propose a unique “one-excitation-to-three-emissions” CPL system through the co-assembl...The modulation of circularly polarized luminescence(CPL) has become an increasingly prominent area of research. In this study,we propose a unique “one-excitation-to-three-emissions” CPL system through the co-assembly of an upconversion system,incorporating one sensitizer(Pt(II) mesotetraphenyl tetrabenzoporphyrine, Pt TPBP) and two annihilators(R/S-DPA and R/SBDP) within liquid crystals. The chiral nature of the annihilators induces a transformation of the nematic liquid crystal into chiral nematic liquid crystals(N*LC), establishing an excellent chiral matrix. Upon the incorporation of the sensitizer Pt TPBP and subsequent excitation at 635 nm, the system demonstrates two independent triplet–triplet annihilation photon upconversion(TTA-UC) with the emission in blue and yellow, aided by thermally activated triplet–triplet energy transfer(TTET). This is accompanied by the simultaneous generation of upconverting circularly polarized luminescence(UC-CPL) and downshifting near-infrared circularly polarized luminescence(DS-CPL) originating from the residual luminescence of Pt TPBP. Remarkably,fine-tuning the ratio between the two annihilators allows the TTA-UC system to exhibit multicolor CPL emission with an amplified luminescence dissymmetry factor(glum, reaching up to 0.6). Our study unveils a previously unreported “one-excitation-to-three-emissions” system and provides a versatile strategy for modulating CPL emissions, surpassing conventional methodologies.展开更多
The enhancement in the efficiency of triplet-triplet annihilation upconversion(TTA-UC)is mainly determined by the triplet energy transfer(TET)and triplet-triplet annihilation(TTA)between the sensitizers and annihilato...The enhancement in the efficiency of triplet-triplet annihilation upconversion(TTA-UC)is mainly determined by the triplet energy transfer(TET)and triplet-triplet annihilation(TTA)between the sensitizers and annihilators.The TET process works efficiently by adjusting the concentration ratio of the sensitizers and annihilators.The efficiency of TTA is determined by the properties of the annihilator.Because TTA is a Dexter-type energy transfer and is affected by the diffusion rate,the energy levels of the excited states and the molecular size are both crucial in TTA.In this study,four isomerized dimers of 9,10-diphenlanthracene(DPA)and anthracene(An)were designed and prepared as annihilators for TTA-UC.The singlet and triplet energy levels could be adjusted by altering the connection position while maintaining the molecular weight and size.When PtOEP was used as the sensitizer,the maximum upconversion efficiency of 9-[4-(9-anthracenyl)phenyl]-10-phenylanthracene(9DPA-9An)was~11.18%.This is four times higher than that of 9,10-diphenyl-2,9-bianthracene(2DPA-9An,2.63%).The calculation of the energies of T_(1)and the higher triplet state(T_(3),because E(T_(2))is similar to the E(T)of these dimers)for these dimers has provided insights into the underlying reasons.These indicated that the energy gap value of 2×E(T_(1))-E(T_(3))is the determining factor for TTA efficiency.This work may provide a better understanding of the excited-state energy levels,which is crucial for designing novel annihilators to enhance the TTA-UCefficiency.展开更多
The solution-processed method for organic light-emitting diodes(OLEDs)offers the benefits of cost-effectiveness and enhanced material utilization.In the multilayer architecture of solution-processed OLEDs(SOLEDs),the ...The solution-processed method for organic light-emitting diodes(OLEDs)offers the benefits of cost-effectiveness and enhanced material utilization.In the multilayer architecture of solution-processed OLEDs(SOLEDs),the role of hole-transport materials(HTMs)is pivotal for cascade hole injection.However,commercial HTMs such as poly-(9,9-dioctylfluorene-alt-N-(4-sec-butylphenyl)-diphenylamine)(TFB)are hampered by incompatible energy levels and redissolution with overlayer solvent,prompting the exploration of cross-linkable HTMs(X-HTMs)for better performance.In this study,we have developed two novel small-molecule X-HTMs,N^(1),N^(1)′-((perfluoropropane-2,2-diyl)bis(4,1-phenylene))bis(N^(4),N^(4)-diphenyl-N^(1)-(4-vinylphenyl)benzene-1,4-diamine)(FTPA-V)and N,N′-((perfluoropropane-2,2-diyl)bis-(4,1-phenylene))bis(9-phenyl-N-(4-vinylphenyl)-9H-carbazol-3-amine)(FPCz-V),which incorporate thermally cross-linkable vinyl groups and electron-rich trifluoromethyl units.The X-HTMs enhance interfacial contact through superior film formation and solvent resistance,along with optimal energy levels.The application of X-HTMs significantly enhances the efficiencies and longevities of blue,green,and red SOLEDs.Specially,blue SOLED incorporating FPCz-V exhibits unprecedented lifetime(LT95)extending to over 150 h,setting a new record for blue SOLEDs.The electrochemistry stability,high bond dissociation energy,and triplet energy levels of X-HTMs can effectively minimize exciton annihilation and prolong the lifetime.These findings underscore the potential of X-HTM optimization to propel the development of stable solution-processed luminescent technologies.展开更多
Efficient green fluorescent organic light-emitting diodes were designed with a phosphorescent metal complex as a singlet exciton sensitizing host(SESH)for achieving high efficiency and low efficiency roll-off through ...Efficient green fluorescent organic light-emitting diodes were designed with a phosphorescent metal complex as a singlet exciton sensitizing host(SESH)for achieving high efficiency and low efficiency roll-off through exciton and polaron management.Tetradentate Pt(Ⅱ)complex(Pt-Trz)possessing a tetradentate ligand with a bulky blocking group not only suppresses the severe formation of excimer or dimer itself but also transfers radiative excitons to fluorescent dopant effectively.The SESH assisted fluorescence(SESHF)device with Pt-Trz as the host exhibits the maximum external quantum efficiency of 13.3%and a lower efficiency roll-off compared with exciplex host device which is a general approach for harvesting triplet excitons.Numerical exciton dynamics modeling unravels that the SESHF device effectively utilizes triplet excitons in the host by intersystem crossing and resonance energy transfer from the triplet state of the host to the singlet state of the terminal emitter.Bimolecular quenching rates of the SESHF device are reduced by 11 times for triplet-triplet annihilation and 1.8 times for tripletpolaron annihilation compared with the exciplex device,which demonstrates that Pt-Trz could be a platform to be used as an efficient host for fluorophores.展开更多
Luminescent materials that can be reversibly switched by electric field stimulation are attractive since the potential application for optoelectronic devices.Here we report a triplet-triplet annihilation upconversion(...Luminescent materials that can be reversibly switched by electric field stimulation are attractive since the potential application for optoelectronic devices.Here we report a triplet-triplet annihilation upconversion(TTA-UC)system with electrophoretic response which is developed as the electrophoretic ink.The TTA-UC system consists of an ionic derivative of 9,10-diphenyl anthracene(DPA)as the annihilator and Pt(II)octaethylporphyrin(PtOEP)as the sensitizer.Upon applying an electric field,migration and enrichment of positively charged DPA derivatives towards the cathode results in a 20%enhancement of TTA-UC.A quasi-solid film for electrically writing is made using the electrophoretic TTA system as the ink and a platinum electrode as a pen.The prototype of TTA-UC ink demonstrates unique luminescence functions upon electrically writing and erasing,providing a promising strategy to develop electronic devices for display,information storage and encryption.展开更多
It has been challenging to develop deep blue organic molecular fluorescent emitters with CIE y(y≤0.08)based on triplet-triplet annihilation(TTA). Here, we report facilely available dianthracenylphenylenebased emitter...It has been challenging to develop deep blue organic molecular fluorescent emitters with CIE y(y≤0.08)based on triplet-triplet annihilation(TTA). Here, we report facilely available dianthracenylphenylenebased emitters, which have a 3,5-di(4-t-butylphenyl)phenyl moiety at the one end and 4-cyanophenyl or 3-pyridyl at the other end, respectively. Both fluorophores show a high glass transition temperature of over 220℃ with a thermal decomposition temperature of over 430℃ at an initial weight loss of1%. The preliminary characterizations of the organic light-emitting diodes(OLEDs) that utilized these nondoped emitters provided high EQEs of 4.6%à5.9% with CIE coordinates(0.15, 0.07–0.08). The analysis of the EL transient decay revealed that TTA contributed to the observed performance. The results show that the new emitters are attractive as a potential TTA-based host to afford stable deep blue fluorescent OLEDs.展开更多
基金supported by For Ying Tung Education Foundation (Grant No.101006)the National Natural Science Foundation of China (Grant Nos.10974157 and 10974159)
文摘The DCM dye doped organic electroluminescence devices with structure of ITO/NPB/Alq 3 : DCM/Alq 3 /LiF/Al were fabricated. From 15 K to room temperature, the magnetic field dependent of electroluminescence (MEL) of devices was investigated. Our observations indicated that the MEL is composed of two effects in different regimes: a low field (0≤B≤40 mT) effect and a high field (B 】 40 mT) effect. For undoped devices, the low field effect exhibits a rapid rising with the increasing field, and the high field effect shows a slow increase and gradually saturates at room temperature. For doped devices, the low field rapid increase is also present, whereas the high field effect displays a decrease with the increasing field. The larger the injection current is, the more apparent the high field decrease is. In addition, the doped device demonstrates less temperature dependence of the high field effect than undoped device, although the undoped devices also present high field decrease of electroluminescence at low temperatures (T≤150 K). Based on the energy level trapping effect due to dye doping and magnetic field modulated triplet exciton annihilation, the experimental results are carefully explained.
基金This work was financially supported by the state foundation for key projects: Fundamental Research on New Generation of Steels (No: G1998061500).
文摘Based on experimental data of positron annihilation technology, electrolyticdissolution technique, electron back-scattered pattern, etc. and by analysis the strengtheningfactors, the strengthening mechanism of ultra-thin hot strip of low carbon steel produced by CSP(Compact Strip Production) technique was investigated. The value of each strengthening mechanism andits contribution percentage to yield strength were achieved. The results show that refinementstrengthening is the predominant strengthening mode; precipitation strengthening and dislocationstrengthening are second to it, their contributions to yield strength are almost equal.
基金The project supported by the Natural Science Foundation of Zhejiang Province under Grant No. Y604106, the Foundation of New Century 151 Talent Engineering of Zhejiang Province, and the Natural Science Foundation of Zhejiang Lishui University under Grant No. KZ05010 Acknowledgments The authors would like to thank professor Chun-Long Zheng for his fruitful and helpful suggestions.
文摘By means of an improved mapping method and a variable separation method, a series of variable separation solutions including solitary wave solutions, periodic wave solutions and rational function solutions） to the （2＋1）-dimensional breaking soliton system is derived. Based on the derived solitary wave excitation, we obtain some special annihilation solitons and chaotic solitons in this short note.
文摘Studying the source of particle properties is the most important goal for scientists, so it was necessary to use the means available to us, which is physical logic to study these properties. In this paper, you will examine how the type of coordinates in which electromagnetic fields are distributed can have a role in detecting particle properties, specifically using the Riemann-Silberstein vector. Because electromagnetism it deals with electric and magnetic fields together for any electromagnetic sentence, and when we study it according to multiple coordinates and study its derivation by changing coordinates, we discover how the electromagnetic sentences are transformed from one particle to another.
文摘Room-temperature ferromagnetism is observed in the O^(+)-implanted AIN films with O+doses of 5×10^(16) cm^(-2)(AIN:Osxion)and 2×10^(17) cm^(-2)(AIN:O_(2x1on)).The observed magnetic anisotropy indicates that the ferromagnetism is attributed to the intrinsic properties of O^(+) -implanted AIN films.The out-of-plane saturation magnetization(Ms)of the AIN:O5×10^(16) is about 0.68 emu/g,much higher than that of AIN:O_(2x1017),0.09 emu/g,which is due to the excessively high O^(+)dose made more O+ions occupy adjacent A1^(3+)positions in forms of antiferromagnetic coupling.Doppler broadening of positron annihilation radiation measurements demonstrate the existence of Al vacancies in the O^(+)-implanted AIN films.The first-principles calculations suggest that the ferromagnetism originates mainly from the Al vacancies.Meanwhile,the formation of divacancies or vacancy clusters by high concentrations of Al vacancies will lead to the transformation of VA-VAi coupling from ferromagnetim to antiferromagnetism,ultimately weakening the ferromagnetism of the sample.
基金supported by the National Natural Science Foundation of China (52173159, 92256304)the National Key Basic R&D Program of Ministry of Science and Technology of the People’s Republic of China (2021YFA1200303)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences (XDB36000000)the Beijing Municipal Science and Technology Commission (JQ21003)。
文摘The modulation of circularly polarized luminescence(CPL) has become an increasingly prominent area of research. In this study,we propose a unique “one-excitation-to-three-emissions” CPL system through the co-assembly of an upconversion system,incorporating one sensitizer(Pt(II) mesotetraphenyl tetrabenzoporphyrine, Pt TPBP) and two annihilators(R/S-DPA and R/SBDP) within liquid crystals. The chiral nature of the annihilators induces a transformation of the nematic liquid crystal into chiral nematic liquid crystals(N*LC), establishing an excellent chiral matrix. Upon the incorporation of the sensitizer Pt TPBP and subsequent excitation at 635 nm, the system demonstrates two independent triplet–triplet annihilation photon upconversion(TTA-UC) with the emission in blue and yellow, aided by thermally activated triplet–triplet energy transfer(TTET). This is accompanied by the simultaneous generation of upconverting circularly polarized luminescence(UC-CPL) and downshifting near-infrared circularly polarized luminescence(DS-CPL) originating from the residual luminescence of Pt TPBP. Remarkably,fine-tuning the ratio between the two annihilators allows the TTA-UC system to exhibit multicolor CPL emission with an amplified luminescence dissymmetry factor(glum, reaching up to 0.6). Our study unveils a previously unreported “one-excitation-to-three-emissions” system and provides a versatile strategy for modulating CPL emissions, surpassing conventional methodologies.
基金supported by the National Natural Science Foundation of China(22133006,21703287)the Natural Science Foundation of Shandong Province(ZR2023QB067,ZR2022MB065)+1 种基金the Science and Technology Program of the University of Jinan(XKY2068-140200568)Major Subject of the University of Jinan(1420702).
文摘The enhancement in the efficiency of triplet-triplet annihilation upconversion(TTA-UC)is mainly determined by the triplet energy transfer(TET)and triplet-triplet annihilation(TTA)between the sensitizers and annihilators.The TET process works efficiently by adjusting the concentration ratio of the sensitizers and annihilators.The efficiency of TTA is determined by the properties of the annihilator.Because TTA is a Dexter-type energy transfer and is affected by the diffusion rate,the energy levels of the excited states and the molecular size are both crucial in TTA.In this study,four isomerized dimers of 9,10-diphenlanthracene(DPA)and anthracene(An)were designed and prepared as annihilators for TTA-UC.The singlet and triplet energy levels could be adjusted by altering the connection position while maintaining the molecular weight and size.When PtOEP was used as the sensitizer,the maximum upconversion efficiency of 9-[4-(9-anthracenyl)phenyl]-10-phenylanthracene(9DPA-9An)was~11.18%.This is four times higher than that of 9,10-diphenyl-2,9-bianthracene(2DPA-9An,2.63%).The calculation of the energies of T_(1)and the higher triplet state(T_(3),because E(T_(2))is similar to the E(T)of these dimers)for these dimers has provided insights into the underlying reasons.These indicated that the energy gap value of 2×E(T_(1))-E(T_(3))is the determining factor for TTA efficiency.This work may provide a better understanding of the excited-state energy levels,which is crucial for designing novel annihilators to enhance the TTA-UCefficiency.
基金supported by the National Natural Science Foundation of China(22275003)Shenzhen Fundamental Research Program(JCYJ20200109140425347)+4 种基金the Development and Reform Commission of Shenzhen Municipality(XMHT20200106002)the Key-Area Research and Development Program of Guangdong Province(2019B010924003)Guangdong Basic and Applied Basic Research Foundation(2020B1515120030)provided by Guangdong Key Laboratory of Flexible Optoelectronic Materials and DevicesGuangdong International Science and Technology Cooperation Base of Optoelectronic Materials and Device Technology。
文摘The solution-processed method for organic light-emitting diodes(OLEDs)offers the benefits of cost-effectiveness and enhanced material utilization.In the multilayer architecture of solution-processed OLEDs(SOLEDs),the role of hole-transport materials(HTMs)is pivotal for cascade hole injection.However,commercial HTMs such as poly-(9,9-dioctylfluorene-alt-N-(4-sec-butylphenyl)-diphenylamine)(TFB)are hampered by incompatible energy levels and redissolution with overlayer solvent,prompting the exploration of cross-linkable HTMs(X-HTMs)for better performance.In this study,we have developed two novel small-molecule X-HTMs,N^(1),N^(1)′-((perfluoropropane-2,2-diyl)bis(4,1-phenylene))bis(N^(4),N^(4)-diphenyl-N^(1)-(4-vinylphenyl)benzene-1,4-diamine)(FTPA-V)and N,N′-((perfluoropropane-2,2-diyl)bis-(4,1-phenylene))bis(9-phenyl-N-(4-vinylphenyl)-9H-carbazol-3-amine)(FPCz-V),which incorporate thermally cross-linkable vinyl groups and electron-rich trifluoromethyl units.The X-HTMs enhance interfacial contact through superior film formation and solvent resistance,along with optimal energy levels.The application of X-HTMs significantly enhances the efficiencies and longevities of blue,green,and red SOLEDs.Specially,blue SOLED incorporating FPCz-V exhibits unprecedented lifetime(LT95)extending to over 150 h,setting a new record for blue SOLEDs.The electrochemistry stability,high bond dissociation energy,and triplet energy levels of X-HTMs can effectively minimize exciton annihilation and prolong the lifetime.These findings underscore the potential of X-HTM optimization to propel the development of stable solution-processed luminescent technologies.
基金supported by Chung-Ang University Research Grants in 2023 and MOTIE(20018956)。
文摘Efficient green fluorescent organic light-emitting diodes were designed with a phosphorescent metal complex as a singlet exciton sensitizing host(SESH)for achieving high efficiency and low efficiency roll-off through exciton and polaron management.Tetradentate Pt(Ⅱ)complex(Pt-Trz)possessing a tetradentate ligand with a bulky blocking group not only suppresses the severe formation of excimer or dimer itself but also transfers radiative excitons to fluorescent dopant effectively.The SESH assisted fluorescence(SESHF)device with Pt-Trz as the host exhibits the maximum external quantum efficiency of 13.3%and a lower efficiency roll-off compared with exciplex host device which is a general approach for harvesting triplet excitons.Numerical exciton dynamics modeling unravels that the SESHF device effectively utilizes triplet excitons in the host by intersystem crossing and resonance energy transfer from the triplet state of the host to the singlet state of the terminal emitter.Bimolecular quenching rates of the SESHF device are reduced by 11 times for triplet-triplet annihilation and 1.8 times for tripletpolaron annihilation compared with the exciplex device,which demonstrates that Pt-Trz could be a platform to be used as an efficient host for fluorophores.
基金the financial support from the National Natural Science Foundation of China(Nos.22273117,22273110 and 22090012)。
文摘Luminescent materials that can be reversibly switched by electric field stimulation are attractive since the potential application for optoelectronic devices.Here we report a triplet-triplet annihilation upconversion(TTA-UC)system with electrophoretic response which is developed as the electrophoretic ink.The TTA-UC system consists of an ionic derivative of 9,10-diphenyl anthracene(DPA)as the annihilator and Pt(II)octaethylporphyrin(PtOEP)as the sensitizer.Upon applying an electric field,migration and enrichment of positively charged DPA derivatives towards the cathode results in a 20%enhancement of TTA-UC.A quasi-solid film for electrically writing is made using the electrophoretic TTA system as the ink and a platinum electrode as a pen.The prototype of TTA-UC ink demonstrates unique luminescence functions upon electrically writing and erasing,providing a promising strategy to develop electronic devices for display,information storage and encryption.
基金supported by the National Key R&D Program of China(2016YFB0400701)NSFC-Guangdong Joint Program(U1801258 and U1301243)+2 种基金Department of Science and Technology of Guangdong Province(2017A050503002)Foundation of Guangzhou Science and Technology Project(201504010012)the support of Dongguan Major Special Project(2017215117010)
文摘It has been challenging to develop deep blue organic molecular fluorescent emitters with CIE y(y≤0.08)based on triplet-triplet annihilation(TTA). Here, we report facilely available dianthracenylphenylenebased emitters, which have a 3,5-di(4-t-butylphenyl)phenyl moiety at the one end and 4-cyanophenyl or 3-pyridyl at the other end, respectively. Both fluorophores show a high glass transition temperature of over 220℃ with a thermal decomposition temperature of over 430℃ at an initial weight loss of1%. The preliminary characterizations of the organic light-emitting diodes(OLEDs) that utilized these nondoped emitters provided high EQEs of 4.6%à5.9% with CIE coordinates(0.15, 0.07–0.08). The analysis of the EL transient decay revealed that TTA contributed to the observed performance. The results show that the new emitters are attractive as a potential TTA-based host to afford stable deep blue fluorescent OLEDs.
