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Triplet-triplet annihilation upconversion materials as electrophoretic inks
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作者 Qiaoyu Zhang Guiwen Luo +5 位作者 Jinping Chen Tianjun Yu Rui Hu Guoqiang Yang Yi Zeng Yi Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第3期439-442,共4页
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
关键词 triplet-triplet annihilation Photon upconversion ELECTROPHORESIS Electrophoretic ink Luminescence display
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Study on the energy level limitations of triplet-triplet annihilation upconversion with anthracene-isomerized dimers as annihilators
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作者 Shanshan Liu Tingting Gou +4 位作者 Xiaojuan Song Riming Hu Heyuan Liu Xiyou Li Xuchuan Jiang 《ChemPhysMater》 2024年第2期187-193,共7页
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
关键词 upconversion annihilATOR triplet-triplet annihilation Energy levels
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Assembly-enhanced triplet-triplet annihilation upconversion in the aggregation formed by Schiff-base Pt(Ⅱ) complex grafting-permethyl-β-CD and 9,10-diphenylanthracence dimer 被引量:1
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作者 Hongxia Lai Ting Zhao +3 位作者 Yurong Deng Chunyin Fan Wanhua Wu Cheng Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第11期1979-1983,共5页
Water-soluble triplet sensitizer with permethyl-β-cyclodextrin(PMCD)grafting on a Schiff-base Pt(II)complex(Pt-2),in which PMCD unit serves as a host for binding the acceptors and the Schiff-base Pt(II)complex serves... Water-soluble triplet sensitizer with permethyl-β-cyclodextrin(PMCD)grafting on a Schiff-base Pt(II)complex(Pt-2),in which PMCD unit serves as a host for binding the acceptors and the Schiff-base Pt(II)complex serves as a triplet sensitizer,was synthesized to investigate the effect of supramolecular complexation and assembly on the triplet-triplet annihilation upconversion emission in water.9,10-Diphenylanthracence(DPA)carboxylate(A-1)and its dimer(A-2)in which two DPA carboxylate were covalently linked with an alkyl chain were synthesized as triplet acceptors which also play a role of guest molecules for PMCD.A-1 and A-2 showed high affinity with PMCD,and A-2 can readily aggregate in water and form micron sized assemblies due to the hydrophobic effect andπ-πstacking of anthracene core in A-2.The efficiency of TTA-UC was demonstrated to be enhanced by a synergistic effect of host-guest complexation of Pt-2 with A-2 and the self-aggregation of the acceptor A-2,which facilitated the energy transfer and energy fusion among donor and acceptor. 展开更多
关键词 triplet-triplet annihilation upconversion Host-guest interactions SELF-AGGREGATION Permethyl-β-CD
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Recent Advances in Triplet-Triplet Annihilation Upconversion for Bioimaging and Biosensing 被引量:1
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作者 Wenyue Lin Jiayao Li +2 位作者 Hongjuan Feng Fang Qi Ling Huang 《Journal of Analysis and Testing》 EI CSCD 2023年第4期327-344,共18页
Photon upconversion is an anti-Stokes process that converts low-energy photons into high-energy photons.The use of upconversion luminescence can avoid the autofluorescence of biological tissue and realize background-f... Photon upconversion is an anti-Stokes process that converts low-energy photons into high-energy photons.The use of upconversion luminescence can avoid the autofluorescence of biological tissue and realize background-free bioimaging with a high signal-to-noise ratio at a low power density.In addition,the excitation of red or near-infrared light facilitates the reduction of photodamage in biological tissues and subsequent bioimaging of deep tissue features in vivo.Meanwhile,upconversion emission-mediated bio sensing offers both high sensitivity and low detection limits for quantitative analysis of the target substances in complicated biological samples.Due to its high upconversion quantum yield,low excitation power density,and tunable absorption and emission wavelengths,triplet-triplet annihilation upconversion(TTA-UC)has garnered considerable interest for bioimaging and biosensing.This review will introduce the fundamental concepts of TTA-UC,the factors that influence TTA-UC materials,and the methodologies for preparing TTA-UC materials.The important progress of TTA-UC in bioimaging and bio sensing in recent years will also be discussed in detail in vitro and in vivo.Furthermore,the current challenges of TTA-UC in bioimaging and biosensing will be discussed,along with potential solutions. 展开更多
关键词 triplet-triplet annihilation upconversion BIOIMAGING BIOSENSING
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A Fluorescein Derivative Chemosensor Combined with Triplet-Triplet Annihilation Upconversion System for Ratiometric Sensing of Cysteine
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作者 Shuoran Chen Fuming Chen +3 位作者 Yanling Li Yuyang Wang Xiaomei Wang Changqing Ye 《Journal of Analysis and Testing》 EI CSCD 2023年第4期369-376,共8页
A derivative of fluorescein,fluorescein O,O-diacrylate(FODA),was utilized in a triplet-triplet annihilation upconversion(TTA-UC)system to develop a composite ratiometric chemosensor capable of detecting cysteine(Cys).... A derivative of fluorescein,fluorescein O,O-diacrylate(FODA),was utilized in a triplet-triplet annihilation upconversion(TTA-UC)system to develop a composite ratiometric chemosensor capable of detecting cysteine(Cys).FODA acted as both the probe for Cys and the energy acceptor for upconversion(UC)emission,thereby making UC a responsive signal to Cys.In addition,the phosphorescence signal of the sensitizer in the TTA-UC system remained constant and did not respond to Cys,making it an ideal internal reference signal for constructing a ratiometric sensor.Through this simple strategy,traditional fluorescent probes can be combined with TTA-UC system to establish a ratiometric sensing platform,which can be applied in more scenarios due to the longer wavelength excitation. 展开更多
关键词 triplet-triplet annihilation upconversion Ratiometric sensor Fluorescein derivative CYSTEINE
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Triplet−Triplet Annihilation-Based Photon Upconversion with a Macrocyclic Parallel Dimer
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作者 Catherine H.Mulyadi Masanori Uji +2 位作者 Bhavesh Parmar Kana Orihashi Nobuhiro Yanai 《Precision Chemistry》 2024年第10期539-544,共6页
The integration of multiple chromophore units into a single molecule is expected to improve the performance of photon upconversion based on triplet−triplet annihilation(TTA-UC)that can convert low energy photons to hi... The integration of multiple chromophore units into a single molecule is expected to improve the performance of photon upconversion based on triplet−triplet annihilation(TTA-UC)that can convert low energy photons to higher energy photons at low excitation intensity.In this study,a macrocyclic parallel dimer of 9,10-diphenylanthracene(DPA)with a precisely parallel orientation,named MPD-2,is synthesized,and its TTAUC properties are investigated.MPD-2 shows a green-to-blue TTA-UC emission in the presence of a triplet sensitizer,platinum octaethylporphyrin(PtOEP).Compared to monomeric DPA,MPD-2 results in an enhancement of the spin statistical factor of TTA and a decrease in the excitation light intensity due to the intramolecular TTA process.The obtained structure−property relationship provides important information for the further improvement of TTA-UC properties. 展开更多
关键词 photon upconversion triplettriplet annihilation macrocyclic parallel dimer spin statistical factor anthracene
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Dual Triplet Sensitization Strategy for Efficient and Stable Triplet–Triplet Annihilation Upconversion Perovskite Solar Cells 被引量:2
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作者 Wangping Sheng Jia Yang +7 位作者 Xiang Li Jiaqi Zhang Yang Su Yang Zhong Yanda Zhang Lingyun Gong Licheng Tan Yiwang Chen 《CCS Chemistry》 CAS CSCD 2023年第3期729-740,共12页
The novel triplet–triplet annihilation(TTA)upconversion(UC)field of rubrene(Rub)and dibenzotetraphenylperiflanthene(DBP)sensitized by bulk metal halide perovskite,integrated with copper-2,3,9,10,16,17,23,24-octafluor... The novel triplet–triplet annihilation(TTA)upconversion(UC)field of rubrene(Rub)and dibenzotetraphenylperiflanthene(DBP)sensitized by bulk metal halide perovskite,integrated with copper-2,3,9,10,16,17,23,24-octafluorophthalocyanine(F_(8)CuPc)as cosensitizer,have been investigated in perovskite solar cells(PVSCs)to minimize sub-bandgap photon transmission loss.The firm hydrogen bonding interaction(F…H–N between F_(8)CuPc and MA+),cation-πinteraction(MA+with Rub),and the hydrophobic characteristic of additives enable F_(8)CuPc:Rub:DBP dually-sensitized p-i-n PVSCs based on MAPbI_(3)and Cs_(0.05)(FA_(0.83)MA_(0.17))_(0.95)Pb(Br_(0.17)I_(0.83))_(3)absorbers to attain champion efficiencies of 20.83%and 21.51%,respectively.Furthermore,due to the excellent photochemical and thermal stability of F_(8)CuPc,the corresponding PVSCs can maintain nearly 80%of the original efficiencies exposed to air with 50∼70%relative humidity over 1100 h and N_(2)at 85℃for 300 h. 展开更多
关键词 perovskite solar cells upconversion triplet-triplet annihilation cosensitizer
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Multiple Resonance Thermally Activated Delayed Fluorescence Sensitizers Enable Green-toUltraviolet Photon Upconversion:Application in Photochemical Transformations
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作者 Yaxiong Wei Ke Pan +3 位作者 Xiaosong Cao Yuanming Li Xiaoguo Zhou Chuluo Yang 《CCS Chemistry》 CAS 2022年第12期3852-3863,共12页
Efficient visible-to-ultraviolet(UV)triplet-triplet annihilation upconversion(TTA-UC)with large anti-Stokes shift is highly promising for solar-powered and indoor applications.Nonetheless,the excitationwavelengthis co... Efficient visible-to-ultraviolet(UV)triplet-triplet annihilation upconversion(TTA-UC)with large anti-Stokes shift is highly promising for solar-powered and indoor applications.Nonetheless,the excitationwavelengthis confined to the blue region(<450 nm),mainly due to large energy loss during triplet sensitization,resulting in reduced photon utilization efficiency in practical scenarios.Herein,a series of multiple resonance thermally activated delayed fluorescence(MR-TADF)compounds are developed as purely organic sensitizers for the purpose of energy-loss reduction,which also feature intense absorbance in the visible region,high intersystem crossing efficiencies,and long triplet lifetimes.By pairing the MR-TADF sensitizers with appropriate acceptors,green-to-UV TTA-UC systems were realized with an anti-Stokes shift up to 1.05 eV,upconversion quantum yield up to 8.6%,and threshold excitation intensity as low as 9.2 mW cm^(−2) in solution.The TTA-UC pairs were applied as internal or external sources of UV photons to trigger energy-demanding photopolymerization and photoligation reactions even under excitation of low-power-density green light-emitting diode light,revealing the broad utility of thesemolecular upconverters.This work unlocks the huge potential of MR-TADF-type sensitizers in upconversion applications. 展开更多
关键词 triplet-triplet annihilation upconversion visible-to-ultraviolet upconversion multiple resonance photochemical reactions
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Recent research progress for upconversion assisted dye-sensitized solar cells 被引量:1
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作者 Xugeng Guo Wenpeng Wu +3 位作者 Yuanyuan Li Jinglai Zhang Li Wang Hans Ågren 《Chinese Chemical Letters》 CSCD 2021年第6期1834-1846,共13页
Upconversion(UC)technology makes it possible to harvest infrared(IR)light from the sun and has increasingly been employed in recent years to improve the efficiency of solar cells.The progress in the area concerns both... Upconversion(UC)technology makes it possible to harvest infrared(IR)light from the sun and has increasingly been employed in recent years to improve the efficiency of solar cells.The progress in the area concerns both research on fundamental principles and processes of UC and technologies of device fabrication.Significant increase of important solar cell parameters,like short-circuit photocurrent density and open-circuit photovoltage as well as the total photon-to-current efficiency,has been accomplished.We here review the research published during the last few years in the area,in particular we consider the two most cherished techniques,namely the incorporation of upconverting nanophosphors directly into the photoanodes of the solar cells and the introduction of plasmonic metal nanoparticles co-existing with the UC particles.Other ways to achieve strong field enhancement,and the use of the non-linear nature of UC,is to apply microlenses,with or without assisting plasmonic excitation.Further enhanced UC action has been demonstrated by broad band and effective harvesting by organic IR antennas,with subsequent mediation by an intermediate nanoshell of the energy into the upconverting core.Codoping,nanohybrid and layer-by-layer technologies involving upconverting particles as well as the use of upconverting nanoparticles in hole-transport and electrolyte layers,tested in recent works,are also reviewed.While most of these technologies employ upconverting rare earth metals for sequential photon absorption,the main alternative technique,namely triplet-triplet annihilation UC using organic materials,is also reviewed.It is our belief that all these approaches will be further much researched in the near future,with potentially great impact on solar cell technology. 展开更多
关键词 upconversion nanoparticles Dye-sensitized solar cells Infrared light triplet-triplet annihilation Photovoltaic systems
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Amplified circularly polarized luminescence enabled by photon upconversion in spin-coating cellulose matrix
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作者 Lingxia Liu Jinping Chen +4 位作者 Tianjun Yu Rui Hu Guoqiang Yang Yi Zeng Yi Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第3期313-316,共4页
It is of great significance to construct organic circularly polarized luminescence systems(CPL) with large luminescence dissymmetry factors(g_(lum)) for practical applications. Here we report organic CPL systems const... It is of great significance to construct organic circularly polarized luminescence systems(CPL) with large luminescence dissymmetry factors(g_(lum)) for practical applications. Here we report organic CPL systems constructed by merging triplet-triplet annihilation upconversion chromophores in cellulose matrices. The chirality of the matrix is transferred to the achiral chromophores of photon upconversion and then the multistep energy transfer processes of upconversion amplify g_(lum). The g_(lum)value of upconversion CPL in the left-handed ethyl cellulose and the right-handed(acetyl) ethyl cellulose are up to +0.1 and -0.15, respectively. The study provides a straightforward approach for constructing solid organic upconversion CPL materials with large g_(lum), which may expand the application potentials of organic chiroptical materials. 展开更多
关键词 Circularly polarized luminescence Photon upconversion CELLULOSE CHIRALITY triplet-triplet annihilation
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重原子效应对MR-TADF分子三重态和上转换性能的影响
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作者 魏亚雄 易凯 +1 位作者 段豆豆 许新胜 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第10期89-96,共8页
含有重原子的多重共振热激活延迟荧光(MR-TADF)表现出低能量损失、强烈吸收、高系间窜跃(ISC)效率和长三重态寿命.本文选择3种不含重金属原子的MR-TADF分子,分别结合氧、硫和硒原子(BN-2O,BN-2S和BN-2Se);利用理论计算和纳秒瞬态吸收光... 含有重原子的多重共振热激活延迟荧光(MR-TADF)表现出低能量损失、强烈吸收、高系间窜跃(ISC)效率和长三重态寿命.本文选择3种不含重金属原子的MR-TADF分子,分别结合氧、硫和硒原子(BN-2O,BN-2S和BN-2Se);利用理论计算和纳秒瞬态吸收光谱研究了这些分子的重原子效应,BN-2O,BN-2S和BN-2Se的ISC效率分别确定为39.4%,74.7%和95.0%,且三重态寿命均超过10μs.由BN-2Se和1,4-双(三异丙基硅乙炔基)萘(1,4-DTNA)组成的上转换系统在溶液中获得了高达8.7%的上转换量子产率(Φ_(UC),最大值为50%),且阈值激发强度(I_(th))为1.7 mW/cm^(2),低于太阳光辐照度(2.7 mW/cm^(2)).此外,廉价的BN-2S和BN-2O也表现出良好的上转换量子产率,分别为5.9%和3.9%,I_(th)也分别低至6.2和15 mW/cm^(2). 展开更多
关键词 多重共振热活化延迟荧光 三重态-三重态湮灭上转换 重原子效应
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卟啉钯敏化剂构效性质与三线态-三线态湮灭上转换性能研究 被引量:2
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作者 叶常青 于雪 +3 位作者 陈硕然 梁作芹 周宇扬 王筱梅 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2021年第1期71-79,共9页
上转换发光是一种将长波长的激发光转化为短波长发射的反斯托克斯发光现象,三线态-三线态湮灭上转换(TTA-UC)能够在较低密度能量下被激发,且上转换量子产率高,因此获得研究者们广泛关注。关于敏化剂分子结构与上转换发光性能相关性的研... 上转换发光是一种将长波长的激发光转化为短波长发射的反斯托克斯发光现象,三线态-三线态湮灭上转换(TTA-UC)能够在较低密度能量下被激发,且上转换量子产率高,因此获得研究者们广泛关注。关于敏化剂分子结构与上转换发光性能相关性的研究一直是TTA-UC研究领域的重要热点,选择两种代表性的卟啉钯光敏剂[PdOEP-八乙基卟啉钯(Ⅱ)和PdBrTPP-四溴苯基卟啉钯(Ⅱ)]与蒽衍生物9,10-(4-羟甲基)苯基蒽p-DHMPA发光剂组合上转换体系作为研究模型,通过一系列合成工作获得材料分子后,进一步比较两种敏化剂的光谱性质与体系最终上转换性能之间关系。通过细致研究敏化剂和发光剂的荧光发射和寿命等光谱性质对敏化剂系间窜越,三线态-三线态能量转移及三线态-三线态湮灭等能量传递过程的影响后,发现在532 nm处的摩尔吸光系数PdBrTPP(10.8 cm^-1·mmol^-1)大于PdOEP(3.0 cm^-1·mmol^-1);三线态寿命PdBrTPP(173.13μs)大于PdOEP(109.21μs)。但与p-DHMPA配对时光敏剂与发光剂的三线态能级差ΔE TT,PdOEP(0.140 eV)却高于PdBrTPP(0.062 eV),通过Stern-Volmer方程得到Stern-Volmer猝灭常数K SV和双分子猝灭常数k q值也是PdOEP略高,最终表现出上转换阈值PdOEP/p-DHMPA(22.40 mW·cm^-2)小于PdBrTPP/p-DHMPA(29.78 mW·cm^-2),上转换发光效率ΦUC,PdOEP/p-DHMPA(28.3%)大于PdBrTPP/p-DHMPA(26.8%)。因此,卟啉钯敏化剂的构效对三重态湮灭上转换发光效率影响最为重要的决定因素是敏化剂三线态高低。对于不同的敏化剂,在分子主体结构、摩尔吸光系数与三线态寿命等光谱参数差别不大的情况下,敏化剂的三线态能级越高,就将会具有更大的上转换发光效率。然而如果以总上转换能力指标来评价,PdBrTPP的共轭结构能够提升其在激发波长处吸收更多光子的能力,具有比PdOEP更高的摩尔吸光系数,造成其总上转换能力η比PdOEP高3.4倍。因此从上转换总效能指标来评价,通过敏化剂分子设计调控其在激发光波长处的摩尔吸光系数也不失为一种简单易行的方法。 展开更多
关键词 三线态-三线态湮灭 上转换 敏化剂 构效关系 三线态能级 摩尔吸光系数
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三线态-三线态湮灭上转换机理、材料与应用研究 被引量:1
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作者 王筱梅 陈泉仑 《苏州科技大学学报(自然科学版)》 2022年第1期1-9,共9页
有机上转换(Upconversion,UC)是借助有机分子将长波长(低能量)光转换为短波长(高能量)光的一项技术。依据激发光源的强度不同,上转换又分为强光上转换和弱光上转换两类。强光上转换是指激发光源强度达到MW·cm^(-2)甚至GW·cm^(... 有机上转换(Upconversion,UC)是借助有机分子将长波长(低能量)光转换为短波长(高能量)光的一项技术。依据激发光源的强度不同,上转换又分为强光上转换和弱光上转换两类。强光上转换是指激发光源强度达到MW·cm^(-2)甚至GW·cm^(-2)量级(即为太阳光强度的100万倍以上),如强双光子吸收上转换(Two-photon absorption upconversion,TPA-UC);弱光上转换则是指在mW·cm^(-2)~W·cm^(-2)量级的激发光源照射下获得的上转换,如三线态-三线态湮灭上转换(Triplet-triplet annihilation upconversion,TTA-UC)。由于后者只需要低功率光激发即可实现,所以在新能源、生物医学等诸多领域具有较好的应用前景,对其研究成为热点课题。文章简要介绍国内外在有机弱光上转换材料及应用方面的研究最新进展。 展开更多
关键词 有机弱光上转换 三线态-三线态湮灭上转换 光敏剂 发光剂
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蒽衍生物取代基团与三线态-三线态湮灭上转换性能关系研究
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作者 梁作芹 晏旭 +5 位作者 宋冬冬 张晓波 张家璇 叶常青 陈硕然 王筱梅 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2022年第3期802-807,共6页
三线态-三线态湮灭(TTA)上转换是一种以低功率非相干光泵浦实现大的反斯托克位移的光谱转换技术,具有激发和发射波长可调的特点,在提高太阳能利用率方面具有重要应用价值。经过十几年的发展,敏化剂分子的研究取得了很大进步,而发光剂分... 三线态-三线态湮灭(TTA)上转换是一种以低功率非相干光泵浦实现大的反斯托克位移的光谱转换技术,具有激发和发射波长可调的特点,在提高太阳能利用率方面具有重要应用价值。经过十几年的发展,敏化剂分子的研究取得了很大进步,而发光剂分子的研究相对落后。以敏化剂多吡啶钌(Ⅱ)配合物[Ru(bpy)_(2)Phen]^(2+)和发光剂2-位取代的蒽衍生物(DTACl和DTACN)作为研究对象,复配得到两个弱光上转换体系。通过敏化剂与发光剂的发射和上转换光谱性质,系统研究了蒽2-位取代基团对发光效率、三线态-三线态能量传输(TTET)、TTA等能量传递过程的影响。研究发现DTACl具有比DTACN高的荧光量子产率、大的三线态猝灭常数和高的TTA效率,这些结果最终使得[Ru(bpy)_(2)Phen]^(2+)/DTACl的上转换效率高于[Ru(bpy)_(2)Phen]^(2+)/DTACN。除此之外,利用敏化剂、发光剂的发射光谱,结合密度泛函理论计算,进一步从轨道能级的角度,研究了敏化剂、发光剂三线态能级差与TTET效率之间的关系,以及发光剂三线态与单线态能级差与TTA效率之间的关系。研究结果表明:降低蒽2-位取代基团的吸电子能力,能有效提高发光剂的三线态能级水平,从而减小发光剂与敏化剂的三线态能级差,增大发光剂的三线态与单线态能级差,提高发光剂与敏化剂之间的TTET效率、发光剂的TTA效率,进而提高体系的TTA上转换效率。该工作为开发新型、高效的发光剂分子提供了一种简单、可行的设计思路。 展开更多
关键词 三线态-三线态湮灭 上转换 取代基团 构效关系
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基于上/下转换发光的新型比率荧光温度探针 被引量:2
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作者 陈硕然 郑道远 +2 位作者 刘腾 叶常青 宋延林 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第10期3088-3095,共8页
温度的可视化实时监测,一直都是科学研究的重点方向。荧光传感是一种具有高灵敏度、快速响应、可视化等优点的半侵入式测温方法,在生物医药等领域已被广泛应用。然而,传统荧光探针容易受到外界条件波动的影响而产生误差。为解决这一问题... 温度的可视化实时监测,一直都是科学研究的重点方向。荧光传感是一种具有高灵敏度、快速响应、可视化等优点的半侵入式测温方法,在生物医药等领域已被广泛应用。然而,传统荧光探针容易受到外界条件波动的影响而产生误差。为解决这一问题,可以采用两组荧光检测信号构建比率型荧光探针,通过两组信号的相互校准提高检测的准确性。传统的比率荧光温度探针大多基于下转换荧光发射,这类探针通常由短波长光激发,对生物组织穿透性差且有一定伤害,还会受到生物组织自发荧光的干扰。频率上转换是由长波长激发,短波长发射的一种光致发光现象,由其构建的荧光探针可以克服传统下转换荧光探针的上述缺点。而基于三线态-三线态湮灭(TTA)机理的频率上转换发光体系,由光敏剂和湮灭剂的双分子体系共同构成,因而自身就同时具有上/下转换的发光特性,满足了构建比率型荧光探针的条件。然而目前,基于TTA上转换体系的比率型荧光温度探针还鲜见报导,已报导的工作中仍需要另外添加参比探针。仅通过TTA双分子体系构建的上/下转换比率型荧光温度探针仍然是一大挑战。本文通过将传统的TTA上转换体系(PdOEP/DPA)负载于由温敏型两亲性聚合物Pluronic-F127组装形成的胶束中,形成上转换纳米胶束温度探针。随着温度的升高,聚合物亲水链段水溶性下降,向胶束核心位置收缩,导致负载上转换分子的胶束内部空间体积减小,TTA分子间碰撞概率增大,上转换效率提高,上转换发光的强度也随之提高;与此同时,光敏剂的下转换磷光发射也会发生小幅度的下降。由此上/下转换两组荧光信号构成的比率荧光,可成功实现25~60℃范围内对温度的线性检测,并可通过肉眼观察到体系发光由紫红色向蓝紫色的转变,检测结果的重复性良好。TTA上转换分子通过被温敏聚合物胶束的包覆,既解决了在实际应用中探针水溶性差,以及上转换发光易被氧气淬灭的问题,还为上转换体系提供了温敏性质,实现了上转换发光对温度的精确响应。这种基于上转换纳米胶束的比率型荧光温度探针不仅制备方法简单,具有良好的生物相容性,且检测灵敏度高,可以人眼识别,无需外加参比,对生物体内温度在线监测的实现具有重要意义。 展开更多
关键词 三线态-三线态湮灭频率上转换 两亲性嵌段共聚物 温敏型纳米胶束 比率型荧光探针
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9,10-二杂环取代蒽衍生物制备与三线态-三线态湮灭上转换性能研究 被引量:1
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作者 陈佳 叶常青 +2 位作者 朱赛江 王筱梅 陶绪堂 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2018年第3期715-721,共7页
弱光上转换是基于三线态-三线态湮灭机制将低能量(长波长)的光转换为高能量(短波长)光的一种现象,是通过光敏剂与发光剂之间能量转移实现的。针对当前上转换体系中的光敏剂研究备受关注,而对于同等重要作用的发光剂的研究甚少的现状,利... 弱光上转换是基于三线态-三线态湮灭机制将低能量(长波长)的光转换为高能量(短波长)光的一种现象,是通过光敏剂与发光剂之间能量转移实现的。针对当前上转换体系中的光敏剂研究备受关注,而对于同等重要作用的发光剂的研究甚少的现状,利用Suzuki偶联反应制备了两个新的杂环取代蒽衍生物:9,10-二(3-呋喃)蒽(DFA)和9,10-二(3-噻吩)蒽(DTA)并通过结构表征;以9,10-二杂环取代蒽为发光剂、四苯基卟啉钯衍生物(PdTPPMe和PdTPPCOOH)为三线态光敏剂,研究所构成的光敏剂/发光剂双组分体系中,三线态-三线态能量转移效率(k_Q)、发光剂的延迟荧光寿命(τ_(DF))及发光剂荧光量子产率(Φ_f)等因素对上转换效率(Φ_(UC))的影响。结果表明,高效三线态-三线态能量效率(Φ_(TTT))、快速延迟荧光寿命和大荧光量子产率将有利于提高上转换效率。进一步研究发现,含氧发光剂(DFA)与含羧基的光敏剂(PdTPPCOOH)之间可借助氢键发生有效耦合,有利于光敏剂与发光剂之间的三线态能量转移,导致弱光上转换效率显著提高。在半导体激光器(532nm,70mW·cm^(-2))激发下获得强的绿-转-蓝上转换效率最大可达10.11%。所获得的绿-转-蓝上转换荧光可使Pt/WO_3复合半导体受激;产生氧自由基并可促使香豆素转化为7-羟基香豆素。 展开更多
关键词 9 10-二杂环取代蒽 弱光上转换 三线态-三线态能量转移 延迟荧光 三线态-三线态湮灭
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基于卟啉配合物的弱光上转换研究 被引量:1
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作者 丁平 周立伟 +1 位作者 梁作芹 王筱梅 《苏州科技学院学报(自然科学版)》 CAS 2016年第3期27-31,共5页
基于三线态-三线态湮灭的弱光上转换在光电器件、光反应和生物成像等领域具有潜在的应用前景,近年来受到了科学界的广泛关注。介绍了TTA上转换的机理,着重对TTA上转换三重态敏化剂卟啉配合物的分子设计理念进行了综述,介绍了卟啉配合物... 基于三线态-三线态湮灭的弱光上转换在光电器件、光反应和生物成像等领域具有潜在的应用前景,近年来受到了科学界的广泛关注。介绍了TTA上转换的机理,着重对TTA上转换三重态敏化剂卟啉配合物的分子设计理念进行了综述,介绍了卟啉配合物上转换体系在光电化学方面的应用。 展开更多
关键词 弱光上转换 三线态-三线态湮灭 卟啉配合物 三线态寿命
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兼具三线态-三线态湮灭上转换与单光子吸收上转换特性的氮杂蒽衍生物发光性能研究
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作者 徐磊 朱琳 +5 位作者 张春 叶常青 陈硕然 李琳 梁作芹 王筱梅 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2022年第6期1761-1768,共8页
弱光上转换是将低能量光子转换为高能量光子的过程,在三维荧光显微成像、太阳能电池、光催化等领域具有广泛的潜在应用,因而成为有机荧光材料领域的热点课题。目前基于三线态-三线态湮灭机制有机弱光上转换材料(TTA-UC)的研究已较为深入... 弱光上转换是将低能量光子转换为高能量光子的过程,在三维荧光显微成像、太阳能电池、光催化等领域具有广泛的潜在应用,因而成为有机荧光材料领域的热点课题。目前基于三线态-三线态湮灭机制有机弱光上转换材料(TTA-UC)的研究已较为深入,有关发光机理及应用研究均有较多报道;然而针对另一种有机弱光上转换机理--基于单光子热带吸收的弱光上转换(OPA-UC)的研究目前还较为少见。氮杂蒽衍生物由于具有良好的结构刚性和平面性,高的荧光量子产率,是研究TTA-UC和OPA-UC两种有机上转换发光的理想模型分子结构。通过研究比较三种氮杂蒽衍生物:酚藏花红(PSF)、藏红T(SFT)、亚甲基紫(MTV)各自TTA-UC和OPA-UC的发光性能差异,分析探讨了分子结构对OPA-UC发光性能及TTA-UC敏化效率的构效关系。实验发现酚藏花红和藏红T由于具有较高的荧光量子产率,同时辐射衰减常数较大,其主要衰减过程为辐射衰减;而亚甲基紫具有较高的分子内电荷转移能力(ICT),因而非辐射衰减部分更多。研究三种分子的TTA-UC性能,发现亚甲基紫的三线态能级过低无法进行三线态-三线态能量转移过程,而藏红T由于拥有更高的三线态寿命而具有更高的上转换发光效率(9.69%),是酚藏花红体系(3.16%)的3倍。进一步研究酚藏花红和亚甲基紫的OPA-UC性能差异,发现相同浓度条件(10^(-3)mol·L^(-1))下亚甲基紫(0.12%)的OPA-UC发光效率相较于酚藏花红(0.059%)更高,且随着浓度的升高,亚甲基紫的OPA-UC发光增强效应更大。进一步研究表明,在TTA-UC发光过程中,敏化剂的敏化效率主要受分子三线态寿命以及系间窜跃能力影响,寿命越长,系间窜跃能力越强,敏化效率越高;而在OPA-UC发光过程中,湮灭剂分子的发光学率主要受ICT影响,ICT能力越大,分子发光效率越高。使用氮杂蒽分子廉价易得,对未来高性能TTA-UC和OPA-UC发光分子的设计具有一定的实际意义。 展开更多
关键词 弱光上转换 三线态-三线态湮灭上转换 单光子吸收上转换 氮杂蒽衍生物
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9-蒽甲酸/卟啉钯衍生物的pH响应上转换性能
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作者 陈硕然 陈富铭 +3 位作者 叶常青 韩鹏举 王筱梅 宋延林 《精细化工》 EI CAS CSCD 北大核心 2019年第9期1757-1762,共6页
以9-蒽甲酸(9-ACA)为发光剂,八乙基卟啉钯(Pd OEP)为光敏剂,在二者最佳配比〔n(9-ACA)∶n(Pd OEP)=80∶1〕下,构建了对溶液中氢离子和氢氧根离子具备灵敏响应性的上转换发光体系9-ACA/PdOEP。当pH处于4~8以及8~11时,上转换发光强度均与p... 以9-蒽甲酸(9-ACA)为发光剂,八乙基卟啉钯(Pd OEP)为光敏剂,在二者最佳配比〔n(9-ACA)∶n(Pd OEP)=80∶1〕下,构建了对溶液中氢离子和氢氧根离子具备灵敏响应性的上转换发光体系9-ACA/PdOEP。当pH处于4~8以及8~11时,上转换发光强度均与pH呈现良好的线性关系。参比实验中,单一组分9-ACA本身的荧光强度与pH没有呈现线性关系,证明了9-ACA/Pd OEP体系对于pH的宽范围响应来源于光敏剂与发光剂之间的三线态-三线态能量转移(TTET)过程。 展开更多
关键词 上转换 三线态-三线态湮灭 三线态-三线态能量转移 9-蒽甲酸 PH响应 功能材料
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三重态湮灭光子上转换体系聚合物基质的研究
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作者 钟嘉敏 籍少敏 梁亮 《分析测试学报》 CAS CSCD 北大核心 2019年第9期1150-1154,共5页
三重态-三重态湮灭(TTA)上转换是一种通过多光子机制将低能量光波向高能量光波转换的技术,在太阳能电池、光催化、生物成像、防伪等领域具有潜在的应用前景。传统的TTA上转换一般在无氧溶液中发生,使得其应用领域严重受限。近几年固态TT... 三重态-三重态湮灭(TTA)上转换是一种通过多光子机制将低能量光波向高能量光波转换的技术,在太阳能电池、光催化、生物成像、防伪等领域具有潜在的应用前景。传统的TTA上转换一般在无氧溶液中发生,使得其应用领域严重受限。近几年固态TTA上转换发光材料的发展引起了研究者的关注,该文从TTA上转换体系聚合物基质的状态以及TTA体系在聚合物中的分散形式出发,总结了近十年TTA上转换体系在聚合物基质中的研究进展。 展开更多
关键词 三重态-三重态湮灭 上转换 聚合物 基质
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