The aggregation-induced emission(AIE) phenomenon provides a new direction for the development of organic light-emitting devices. Here, we present a new class of emitters based on 4,4-difluoro-4-bora-3 a,4 a-diaza-s-in...The aggregation-induced emission(AIE) phenomenon provides a new direction for the development of organic light-emitting devices. Here, we present a new class of emitters based on 4,4-difluoro-4-bora-3 a,4 a-diaza-s-indacene(BODIPY), functionalized at different positions with tetraphenylethylene(TPE), which is one of the most famous AIE luminogens. Thanks to this modification, we were able to tune the photoluminescence of the BODIPY moiety from the green to the near-infrared(NIR)spectral range and achieve PL efficiencies of ~50% in the solid state. Remarkably, we observed an enhancement of the AIE and up to ~100% photoluminescence efficiencies by blending the TPE-substituted BODIPY fluorophores with a poly[(9,9-di-noctylfluorene-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,7-diyl)](F8 BT) matrix. By incorporating these blends in organic lightemitting diodes(OLEDs), we obtained electroluminescence peaked in the range 650–700 nm with up to 1.8% external quantum efficiency and ~2 m W/cm2 radiance, a remarkable result for red/NIR emitting and solution-processed OLEDs.展开更多
Metal nanoclusters(MNCs)are ultrasmall metal-organic aggregates,composed of a metal core less than 2 nm and a protecting shell of metal-organic ligand motifs.The controlled aggregation of metal atoms(in the cluster co...Metal nanoclusters(MNCs)are ultrasmall metal-organic aggregates,composed of a metal core less than 2 nm and a protecting shell of metal-organic ligand motifs.The controlled aggregation of metal atoms(in the cluster core)and metal-organic ligand motifs(around the cluster core)renders MNCs with numerous molecule-like properties,among which strong and bright luminescence has attracted extensive basic and applied interests.It has now known that aggregation-induced emission is a feasible mechanism for controlling luminescence of MNCs,which makes it particularly useful in biosensing and bioimaging applications.Although the luminescence fundamentals and design principles largely determine the practicality and effectiveness of MNCs in biosensing and bioimaging applications,a systematic summary of this topic is lacking in the current literature.In this review,we aim to provide a concise discussion of the latest developments in biosensing and bioimaging applications of luminescent MNCs,highlighting their luminescence mechanisms,biosensing principles,and bioimaging strategies.Specifically,we first introduce the recent advances in the synthetic chemistry of MNCs,and then briefly discuss the luminescence fundamentals ofMNCs.Then the design strategy and practicality of luminescent MNCs in biosensing and bioimaging applications are exemplified.We conclude the review with our perspectives on the further development of MNC-based optical probes in biosensing and bioimaging applications.Our review is expected to provide guidance for the future practice of designing and synthesizing luminescent MNCs for biomedical and other applications.展开更多
The aggregate luminescence behavior of organic luminescent materials has been studied extensively.As a new kind of luminescent nanomaterials,carbonized polymer dots(CPDs)not only inherit the stability and biocompatibi...The aggregate luminescence behavior of organic luminescent materials has been studied extensively.As a new kind of luminescent nanomaterials,carbonized polymer dots(CPDs)not only inherit the stability and biocompatibility of carbon materials,but also possess the luminescence tunability,water solubility,and high photoluminescence quantum yield of organic luminescent materials,rendering them a strong candidate for the next generation of light-emitting materials.Previously,people mainly understood its luminescence from the perspective of carbon materials,but some luminescence mechanisms are still unclear.In this review,we discuss the luminescence mechanism by referring to organic luminescent materials with emphasis on their aggregation behavior.Firstly,three representative aggregate luminescence phenomena of organic luminescent materials are briefly introduced.Chromophores present in CPDs are elaborated to further discuss the potential interactions between them,with emphasis on the role of crosslinked polymer networks.On this basis,some special luminescence phenomena of CPDs in the aggregate state are summarized,and relevant mechanisms are discussed in detail to consolidate relevant statements.展开更多
Herein,we prepared two novel pairs of enantiomeric gold cluster complexes,AU4PL4/Au4PD4 and(Au4L4)n/(Au4D4)n with atomic precision.In Au4PL4/Au4PD4,the discrete chiral Au4-based aggregation-induced emission(AIE)lumino...Herein,we prepared two novel pairs of enantiomeric gold cluster complexes,AU4PL4/Au4PD4 and(Au4L4)n/(Au4D4)n with atomic precision.In Au4PL4/Au4PD4,the discrete chiral Au4-based aggregation-induced emission(AIE)luminogens are separated by bulky substitutes.The corresponding aggregates are cyan-emitting with a photoluminescence quantum yield(PLQY)of 14.4%.Upon decreasing the size of the substituents,these chiral Au4 clusters are strung together by inter-cluster Au-Au interactions,which cause a low-energy green emission from the aggregated(Au4L4)n/(Au4D4)n with a much higher PLQY of 41.4%and more intense circularly polarised photoluminescence(CPL)with a dissymmetry factor|gPL|of 7.0×10^−3.Using(Au4L4)n/(Au4D4)n,circularly polarised organic light-emitting diodes(CP-OLEDs)were for the first time fabricated with|gEL|=|gPL|.These findings signify that inter-cluster metallophilic interactions are a new and important type of driving force for AIE and crystallization-induced emission(CIE),suggesting great potential of CPL-active metal clusters in CP-OLEDs.展开更多
Despite the rapid development of probes for targeting single organelle, the construction of robust dual-organelle targeting probes with multicolor emission was rarely reported. Herein, two dual-emissive aggregation-in...Despite the rapid development of probes for targeting single organelle, the construction of robust dual-organelle targeting probes with multicolor emission was rarely reported. Herein, two dual-emissive aggregation-induced emission luminogens(AIEgens)with donor-π-acceptor structures were designed and synthesized, namely QT-1 and QF-2. Both two AIEgens exhibited excitation wavelength-dependence defying the Kasha's rule, and could stain lipid droplets(LDs) and mitochondria in blue and red fluorescence, respectively. Moreover, thanks to the near-infrared emission and abundant reactive oxygen species(ROS) generation efficiency of QT-1, it was chosen as a photodynamic therapy agent to selectively kill cancer cells from normal cells. Upon light irradiation, an obvious decrease of mitochondrial membrane potential(MMP) and serious change of mitochondrial shape in cells were observed, which corresponded to the efficient inhibition of tumor growth in vivo. This work afforded a promising strategy for the construction of multicolor emission by tuning anti-Kasha behaviors and expanding their application in dualorganelle targeting-based phototheranostics.展开更多
The development of solid-state materials with switchable luminescence in response to stimuli remains a challenge,especially for organic materials.While crystal water significantly impacts the absorption spectra of org...The development of solid-state materials with switchable luminescence in response to stimuli remains a challenge,especially for organic materials.While crystal water significantly impacts the absorption spectra of organic crystals,it is unclear whether the emission spectra of organic luminescent materials can be systematically manipulated by water.In this study,we successfully obtained curcumin monohydrate(Form X),a channel-type hydrate exhibiting crystallization-induced emission(CIE)at 608 nm(orange fluorescence),which contrasted with the conventional forms of aggregation-caused quenching(ACQ).Thermal treatment induced the release of hydration water,resulting in a new anhydrate(Form IV)that emitted yellow-green fluorescence with the emission peak at 575 nm.Additionally,this approach can be used to track the absorption of curcumin crystals following subcutaneous or intramuscular delivery.The hydratemediated single-crystal-to-single-crystal transition(SCSC)and its associated luminescence transition were reversible and responsive to temperature,offering a green approach for synthesizing and designing aggregation-induced-emission(AIE)-based intelligent luminescent devices for detecting air humidity or drug absorption.展开更多
Two diphosphine-protected superatom gold selenido nanoclusters,[Au_(8)Se_(2)(dppm)4]^(2+)(SD/Au_(8)a,dppm=Ph_(2)PCH_(2)PPh_(2))and[Au_(8)Se_(2)(dppe)4]^(2+)(SD/Au_(8)b,dppe=Ph_(2)P(CH_(2))2PPh_(2)),were obtained by th...Two diphosphine-protected superatom gold selenido nanoclusters,[Au_(8)Se_(2)(dppm)4]^(2+)(SD/Au_(8)a,dppm=Ph_(2)PCH_(2)PPh_(2))and[Au_(8)Se_(2)(dppe)4]^(2+)(SD/Au_(8)b,dppe=Ph_(2)P(CH_(2))2PPh_(2)),were obtained by the reduction of[Au(SMe2)Cl]in the presence of Ph3PSe as the selenium ion releasing agents.Both can be regarded as“superatoms”with 1S^(2)configuration based on the spherical Jellium model.Despite the same metal-ligand binding motifs on the surface and the intrinsic C_(2)molecular symmetry,the configurations of Au_(8)Se_(2)kernels in them are different in terms of Au-Au bonded metallic frameworks.SD/Au_(8)a displays a heart-shaped[core+exo]type structure(Au4 tetrahedron core+two exo Au2Se units),whereas the two exo Au_(2)Se counterparts in SD/Au_(8)b are additionally locked by an obvious Au-Au bond,forming a distorted hexagonal Au6 ring with two capping AuSe units appended above and below it.Consequently,they showed different photophysical properties as reflected by their electronic absorption and emission spectra.Especially,both SD/Au_(8)a and SD/Au_(8)b exhibit blue-shifted thermochromic luminescence upon cooling from 293 to 83 K but the latter exhibits anomalous emission intensity evolution trends due to the occurrence of temperature-induced phase transition as revealed by varied-temperature crystallographic analyses.This work not only clearly illustrates the significance of ligands on tuning the kernel structure but also provides two rarely comparable examples for better understanding of the structure-property relationship of gold nanoclusters.展开更多
Carbon dots(CDs)with aggregation-induced emission(AIE)have sparked significant interest in multidimensional anti-counterfeiting due to their exceptional fluorescence properties.However,the preparation of AIE CDs with ...Carbon dots(CDs)with aggregation-induced emission(AIE)have sparked significant interest in multidimensional anti-counterfeiting due to their exceptional fluorescence properties.However,the preparation of AIE CDs with multicolor solid-state fluorescence remains a formidable challenge due to its complicated construction.In the present work,a novel class of multicolor AIE CDs(M-CDs)were fabricated using selected precursor(salicylic acid,thiosalicylic acid,and 2,2'-dithiodibenzoic acid),with an eco-friendly,low-cost one-pot solvothermal method.In the dilute organic solution,M-CDs manifested blue emission,but upon aggregation in the presence of water,the red,yellow,green,and blue emissions were displayed due to the AIE effect.Structural analysis,coupled with theoretical calculations,revealed that the increase in the size of sp2 domains would lower the Eg and cause a red-shift emission wavelength.Significantly,the continuous emission of M-CDs from blue to red can be utilized as ink for multimode printing,enabling the creation of a variety of school badges and quick response codes.These findings hold promising implications for multi-information encryption applications.展开更多
Energy transfer is ubiquitous in natural and artificial lightharvesting systems,and coherent energy transfer,a highly efficient energy transfer process,has been accepted to play a vital role in such systems.However,th...Energy transfer is ubiquitous in natural and artificial lightharvesting systems,and coherent energy transfer,a highly efficient energy transfer process,has been accepted to play a vital role in such systems.However,the energy oscillation of coherent energy transfer is exceedingly difficult to capture because of its evanescence due to the interaction with a thermal environment.Here a microscopic quantum model is used to study the time evolution of electrons triggered energy transfer between coherently coupled donoracceptor molecules in scanning tunneling microscope(STM).A series of topics in the plasmonic nanocavity(PNC)coupled donor-acceptor molecules system are discussed,including resonant and nonresonant coherent energy transfer,dephasing assisted energy transfer,PNC coupling strength dependent energy transfer,Fano resonance of coherently coupled donor-acceptor molecules,and polariton-mediated energy transfer.展开更多
Through-space conjugation(TSC)is a noncovalently electronic interaction that is emerging as a potential complement to through-bond conjugation(TBC)-based strategies for constructing luminescent materials.However,the d...Through-space conjugation(TSC)is a noncovalently electronic interaction that is emerging as a potential complement to through-bond conjugation(TBC)-based strategies for constructing luminescent materials.However,the design of efficient luminogens based on TSC is currently challenging due to a lack of established structure-property understanding.This is particularly true in the case of luminogens displaying aggregation-induced emission(AIE)effects.In this work,three terphenyl derivatives were prepared,and their photophysical properties were systemically studied.It was found that relative to the corresponding m-and p-linked analogues,the electronic interaction of TBC is weakened while the strength of TSC is commensurately enhanced in the constitutional isomer containing an o-linked fjordtype subunit.Within this set of luminogens,the presence of a fjord-type arrangement promotes a transformation from aggregation-caused quenching to AIE.Further investigations involving congeneric quaterphenyl and pentphenyl isomers support the universality of the fjord-type unit as a framework for synthesizing AIE-active luminogens(AIEgens)with inherent TSC.This work not only provides a novel set of AIEgens but also establishes the utility of TSC in controlling the photophysical properties of nonconventional and twisted luminogens.展开更多
In the sewage treatment process,facilitating the conversion of pollutants into value-added resources holds great potential for reducing the amount of greenhouse gas emissions and promoting economic circulation.Cyanoph...In the sewage treatment process,facilitating the conversion of pollutants into value-added resources holds great potential for reducing the amount of greenhouse gas emissions and promoting economic circulation.Cyanophycin granule polypeptide(CGP),a recently discovered high value-added biopolymer present in activated sludge,has provided new avenues for the recovery of resources.However,the mechanisms that regulate CGP synthesis and the characteristics of this biopolymer in activated sludge remain unclear thus far.This study investigated the synthesis of CGP,polyhydroxyalkanoates(PHA),and alginate-like exopolysaccharides(ALE)in various microbial aggregates under different carbon sources feeding conditions.Our results showed that the CGP yields was superior that of PHA and ALE when subjected to identical carbon source feeding conditions.Furthermore,biofilm was more conducive to CGP accumulation than floc sludge.Compared with glucose and methanol,sodium acetate significantly enriched the CGP synthetase-encoding gene(cphAabundance=~17419),resulting in the highest CGP yield(average 107.1 mg/g MLSS)in both biofilm and floc sludge.This study is the first to reported the characteristic fluorescence of CGP(Ex/Em=~360/450 nm)caused by the aggregated luminescence of arginine on the side chains.Overall,this study highlights the potential application of CGP as a fluorescent material and offers insights into CGP recovery from activated sludge in wastewater treatment plants.展开更多
Ion beam-induced luminescence(IBIL) experiments were performed to investigate the in situ luminescence of GaN/Al_(2)O_(3) at varying ion energies,which allowed for the measurement of defects at different depths within...Ion beam-induced luminescence(IBIL) experiments were performed to investigate the in situ luminescence of GaN/Al_(2)O_(3) at varying ion energies,which allowed for the measurement of defects at different depths within the material.The energies of H^(+)were set to 500 keV,640 keV and 2 MeV,the Bragg peaks of which correspond to the GaN film,GaN/Al_(2)O_(3) heterojunction and Al_(2)O_(3) substrate,respectively.A photoluminescence measurement at 250 K was also performed for comparison,during which only near band edge(NBE) and yellow band luminescence in the GaN film were observed.The evolution of the luminescence of the NBE and yellow band in the GaN film was discussed,and both exhibited a decrease with the fluence of H^(+).Additionally,the luminescence of F centers,induced by oxygen vacancies,and Cr^(3+),resulting from the ^(2)E →^(4)A_(2) radiative transition in Al_(2)O_(3),were measured using 2 MeV H^(+).The luminescence intensity of F centers increases gradually with the fluence of H^(+).The luminescence evolution of Cr^(3+)is consistent with a yellow band center,attributed to its weak intensity,and it is situated within the emission band of the yellow band in the GaN film.Our results show that IBIL measurement can effectively detect the luminescence behavior of multilayer films by adjusting the ion energy.Luminescence measurement can be excited by various techniques,but IBIL can satisfy in situ luminescence measurement,and multilayer structural materials of tens of micrometers can be measured through IBIL by adjusting the energy of the inducing ions.The evolution of defects at different layers with ion fluence can be obtained.展开更多
Understanding the relationship between structure and properties is critical to the development of solidstate luminescence materials with desired characteristics and performance optimization. In this work, we elaborate...Understanding the relationship between structure and properties is critical to the development of solidstate luminescence materials with desired characteristics and performance optimization. In this work, we elaborately designed and synthesized a pair of mononuclear iridium(Ⅲ) complexes with similar structures but different degrees of cationization. [Ir2-f][2PF_(6)] with two counterions is obtained by simple Nmethylation of the ancillary ligand of [Ir1-f][PF_(6)] which is a classic cationic iridium(Ⅲ) complex. Such a tiny modification results in tremendously different optical properties in dilute solutions and powders.[Ir1-f][PF_(6)] exhibits weak light in solution but enhanced emission in solid-state as well as poly(methyl methacrylate) matrix, indicative of its aggregation-induced emission(AIE) activity. On the sharp contrary, [Ir2-f][2PF_(6)] is an aggregation-caused quenching(ACQ) emitter showing strong emission in the isolated state but nearly nonemissive in aggregation states. Benefiting from the appealing characteristics of mechanochromic luminescence and AIE behavior, [Ir1-f][PF_(6)] has been successfully applied in reversible re-writable data recording and cell imaging. These results might provide deep insights into AIE and ACQ phenomenon of iridium(Ⅲ) complexes and facilitate the development of phosphorescent materials with promising properties.展开更多
Mechanoluminescent(ML)materials can directly convert external mechanical stimulation into light without the need for excitation from other forms of energy,such as light or electricity.This alluring characteristic make...Mechanoluminescent(ML)materials can directly convert external mechanical stimulation into light without the need for excitation from other forms of energy,such as light or electricity.This alluring characteristic makes ML materials potentially applicable in a wide range of areas,including dynamic imaging of force,advanced displays,information code,storage,and anti-counterfeiting encryption.However,current reproducible ML materials are restricted to sulfide-and oxide-based materials.In addition,most of the reported ML materials require pre-irradiation with ultraviolet(UV)lamps or other light sources,which seriously hinders their practical applications.Here,we report a novel ML material,MgF_(2):Mn^(2+),which emits bright red light under an external dynamic force without the need for pre-charging with UV light.The luminescence properties were systematically studied,and the piezophotonic application was demonstrated.More interestingly,unlike the well-known zinc sulfide ML complexes reported previously,a highly transparent ML film was successfully fabricated by incorporating MgF_(2):Mn^(2+)into polydimethylsiloxane(PDMS)matrices.This film is expected to find applications in advanced flexible optoelectronics such as integrated piezophotonics,artificial skin,athletic analytics in sports.展开更多
[ Objectlve] The paper was to compare the induced resistance of several chemicals on cucumber against Pseudoperonospora cubensis [ Method ] When the cucumber seedlings grew to 4-leaf stage, the second true leaf was tr...[ Objectlve] The paper was to compare the induced resistance of several chemicals on cucumber against Pseudoperonospora cubensis [ Method ] When the cucumber seedlings grew to 4-leaf stage, the second true leaf was treated with salicylic acid, oxalate, chitosan, calcium nitrate and Na2HPO4, the activity of protective enzymes in the third leaf was determined after 7 d. At the same time, inoculation test was also conducted after induced treatment, and the disease condi- tion was coumed. [ Result ] These chemical treatments promoted protective enzyme activities （POD, SOD, PAL, PPO） in different degree, improved the ultra-weak luminescence, and reduced the disease index of cucumber leaves. [ Conclusion] Five chemical treatments expressed good effects on induced resistance. Among the treatments, oxalate had the best induced effect, followed by salicylic acid, chitosan, Na2 HPO4 and calcium nitrate.展开更多
We herein report a new lanthanide metal-organic framework(MOF) that exhibits excellent chemical stability,especially in the aqueous solution over a wide pH range from 1 to 14.In contrast to many reported lanthanide MO...We herein report a new lanthanide metal-organic framework(MOF) that exhibits excellent chemical stability,especially in the aqueous solution over a wide pH range from 1 to 14.In contrast to many reported lanthanide MOFs,this Tb-based MOF emits cyan fluorescence inherited from the integrated AIEactive ligand,rather than Ln3+ ions.More remarkably,its fluorescence signal features a highly selective and sensitive "turn-off" response toward CrO_(4)^(2-),Cr_(2)O_(7)^(2- )and Fe^(3+) ions,highlighted with the low detection limits down to 68.18,69.85 and 138.8 ppm,respectively.Thus,the exceptional structural stability and sensing performance render this material able to be a superior luminescent sensor for heavy metal ions in wastewater.展开更多
To understand the evolution of defects in SiC during irradiation and the influence of temperature,in situ luminescence measurements of 6H-SiC crystal samples were carried out by ion beam induced luminescence(IBIL)meas...To understand the evolution of defects in SiC during irradiation and the influence of temperature,in situ luminescence measurements of 6H-SiC crystal samples were carried out by ion beam induced luminescence(IBIL)measurement under2 MeV H^+ at 100 K,150 K,200 K,250 K,and 300 K.A wide band(400-1000 nm)was found in the spectra at all temperatures,and the intensity of the IBIL spectra was highest at 150 K among the five temperatures.A small peak from 400 nm to 500 nm was only observed at 100 K,related with the D1 defect as a donor-acceptor pair(D-A)recombination.For further understanding the luminescent centers and their evolution,the orange band(1.79 eV)and the green band(2.14 eV)in the energy spectrum were analyzed by Gaussian decomposition,maybe due to the donor-deep defect/conduction band-deep defect transitions and Ti related bound excition,respectively.Finally,a single exponential fit showed that when the temperature exceeded 150 K,the two luminescence centers’resistance to radiation was reduced.展开更多
Herein,a pair of chiral macrocyclic luminogens derived from chiral 1,1-bi(2-naphthol)(BINOL)and tetraphenylethenes(TPEs)have been prepared with high yield via intramolecular McMurry coupling,in which the preferential ...Herein,a pair of chiral macrocyclic luminogens derived from chiral 1,1-bi(2-naphthol)(BINOL)and tetraphenylethenes(TPEs)have been prepared with high yield via intramolecular McMurry coupling,in which the preferential helicity of propeller-shaped TPE units can be tuned via choosing proper chiral BINOL tethers.The preferential chiral geometry of the macrocyclic luminogen was unambiguously confirmed by X-ray crystal crystallography and theoretical calculation,whereas the variable-temperature NMR spectra and chiral HPLC analysis further verified the intramolecular motions.These two chiral macrocyclic luminogens both exhibit obvious aggregation-induced emission behavior and mechanochromic luminescence properties.Furthermore,aggregation attenuated CD signals and circularly polarized luminescence were observed for these two chiral macrocylic luminogens in THF-water mixture and PMMA matrix.These results had paved a new approach toward constructing chiral aggregation-induced emission luminogens(AIEgens)and their structural engineering.展开更多
基金supported by the European Community’s Seventh Framework Programme (FP7/2007-2013) (607585)
文摘The aggregation-induced emission(AIE) phenomenon provides a new direction for the development of organic light-emitting devices. Here, we present a new class of emitters based on 4,4-difluoro-4-bora-3 a,4 a-diaza-s-indacene(BODIPY), functionalized at different positions with tetraphenylethylene(TPE), which is one of the most famous AIE luminogens. Thanks to this modification, we were able to tune the photoluminescence of the BODIPY moiety from the green to the near-infrared(NIR)spectral range and achieve PL efficiencies of ~50% in the solid state. Remarkably, we observed an enhancement of the AIE and up to ~100% photoluminescence efficiencies by blending the TPE-substituted BODIPY fluorophores with a poly[(9,9-di-noctylfluorene-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,7-diyl)](F8 BT) matrix. By incorporating these blends in organic lightemitting diodes(OLEDs), we obtained electroluminescence peaked in the range 650–700 nm with up to 1.8% external quantum efficiency and ~2 m W/cm2 radiance, a remarkable result for red/NIR emitting and solution-processed OLEDs.
基金Ministry of Education,Singapore,Grant/Award Numbers:R-279-000-580-112,R-279-000-538-114China Scholarship Council,Grant/Award Number:201908420311+1 种基金Ministry of Education,Singapore,Grant/Award Numbers:R-279-000-580-112,R-279-000-538-114China Scholarship Council,Grant/Award Number:201908420311。
文摘Metal nanoclusters(MNCs)are ultrasmall metal-organic aggregates,composed of a metal core less than 2 nm and a protecting shell of metal-organic ligand motifs.The controlled aggregation of metal atoms(in the cluster core)and metal-organic ligand motifs(around the cluster core)renders MNCs with numerous molecule-like properties,among which strong and bright luminescence has attracted extensive basic and applied interests.It has now known that aggregation-induced emission is a feasible mechanism for controlling luminescence of MNCs,which makes it particularly useful in biosensing and bioimaging applications.Although the luminescence fundamentals and design principles largely determine the practicality and effectiveness of MNCs in biosensing and bioimaging applications,a systematic summary of this topic is lacking in the current literature.In this review,we aim to provide a concise discussion of the latest developments in biosensing and bioimaging applications of luminescent MNCs,highlighting their luminescence mechanisms,biosensing principles,and bioimaging strategies.Specifically,we first introduce the recent advances in the synthetic chemistry of MNCs,and then briefly discuss the luminescence fundamentals ofMNCs.Then the design strategy and practicality of luminescent MNCs in biosensing and bioimaging applications are exemplified.We conclude the review with our perspectives on the further development of MNC-based optical probes in biosensing and bioimaging applications.Our review is expected to provide guidance for the future practice of designing and synthesizing luminescent MNCs for biomedical and other applications.
基金National Natural Science Foundation of China,Grant/Award Number:21774041。
文摘The aggregate luminescence behavior of organic luminescent materials has been studied extensively.As a new kind of luminescent nanomaterials,carbonized polymer dots(CPDs)not only inherit the stability and biocompatibility of carbon materials,but also possess the luminescence tunability,water solubility,and high photoluminescence quantum yield of organic luminescent materials,rendering them a strong candidate for the next generation of light-emitting materials.Previously,people mainly understood its luminescence from the perspective of carbon materials,but some luminescence mechanisms are still unclear.In this review,we discuss the luminescence mechanism by referring to organic luminescent materials with emphasis on their aggregation behavior.Firstly,three representative aggregate luminescence phenomena of organic luminescent materials are briefly introduced.Chromophores present in CPDs are elaborated to further discuss the potential interactions between them,with emphasis on the role of crosslinked polymer networks.On this basis,some special luminescence phenomena of CPDs in the aggregate state are summarized,and relevant mechanisms are discussed in detail to consolidate relevant statements.
基金This work was supported by the National Science Fund for Distinguished Young Scholars(No.21825106)the National Natural Science Foundation of China(No.21671175)+1 种基金the Program for Science&Technology Innovation Talents in Universities of Henan Province(No.164100510005)the Program for Innovative Research Team(in Science and Technology)in Universities of Henan Province(No.19IRTSTHN022)and Zhengzhou University.
文摘Herein,we prepared two novel pairs of enantiomeric gold cluster complexes,AU4PL4/Au4PD4 and(Au4L4)n/(Au4D4)n with atomic precision.In Au4PL4/Au4PD4,the discrete chiral Au4-based aggregation-induced emission(AIE)luminogens are separated by bulky substitutes.The corresponding aggregates are cyan-emitting with a photoluminescence quantum yield(PLQY)of 14.4%.Upon decreasing the size of the substituents,these chiral Au4 clusters are strung together by inter-cluster Au-Au interactions,which cause a low-energy green emission from the aggregated(Au4L4)n/(Au4D4)n with a much higher PLQY of 41.4%and more intense circularly polarised photoluminescence(CPL)with a dissymmetry factor|gPL|of 7.0×10^−3.Using(Au4L4)n/(Au4D4)n,circularly polarised organic light-emitting diodes(CP-OLEDs)were for the first time fabricated with|gEL|=|gPL|.These findings signify that inter-cluster metallophilic interactions are a new and important type of driving force for AIE and crystallization-induced emission(CIE),suggesting great potential of CPL-active metal clusters in CP-OLEDs.
基金supported by the National Natural Science Foundation of China (52173152, 21805002)Guangdong Basic and Applied Basic Research Foundation (2020A1515110476)+7 种基金the Fund of the Rising Stars of Shaanxi Province (2021KJXX-48)the Shenzhen Science and Technology Program (KQTD20210811090115019)the Major Instrumentation Development Program of the Chinese Academy of Sciences(ZDKYYQ20220008)Shenzhen Basic Research (key project)(China)(JCYJ20210324120011030)the Scientific and Technological Innovation Team of Shaanxi Province (2022TD-36)the National Key R&D Programs(China)(2021YFA0910001)Shaanxi Fundamental Science Research Project for Chemistry&Biology (22JHQ078)the Scientific Research Program Funded by Shaanxi Provincial Education Department (22JK0247)。
文摘Despite the rapid development of probes for targeting single organelle, the construction of robust dual-organelle targeting probes with multicolor emission was rarely reported. Herein, two dual-emissive aggregation-induced emission luminogens(AIEgens)with donor-π-acceptor structures were designed and synthesized, namely QT-1 and QF-2. Both two AIEgens exhibited excitation wavelength-dependence defying the Kasha's rule, and could stain lipid droplets(LDs) and mitochondria in blue and red fluorescence, respectively. Moreover, thanks to the near-infrared emission and abundant reactive oxygen species(ROS) generation efficiency of QT-1, it was chosen as a photodynamic therapy agent to selectively kill cancer cells from normal cells. Upon light irradiation, an obvious decrease of mitochondrial membrane potential(MMP) and serious change of mitochondrial shape in cells were observed, which corresponded to the efficient inhibition of tumor growth in vivo. This work afforded a promising strategy for the construction of multicolor emission by tuning anti-Kasha behaviors and expanding their application in dualorganelle targeting-based phototheranostics.
基金supported by the National Key Research and Development Program of China(2021YFE0103100,2021YFC2400600)the National Natural Science Foundation of China(NSFC)(81925035)+2 种基金the Department of Science and Technology of Guangdong Province(High-Level New R&D Institute 2019B090904008,High-Level Innovative Research Institute 2021B0909050003)the First Batch of Scientific and Technological Innovation Leading Talent Funding Projects in Zhongshan City(LJ2021001)the Introduced Scientific Research and Innovation Team Project in Zhongshan City(Lingnan Pharmaceutical Research and Innovation Team,CXTD2022011)。
文摘The development of solid-state materials with switchable luminescence in response to stimuli remains a challenge,especially for organic materials.While crystal water significantly impacts the absorption spectra of organic crystals,it is unclear whether the emission spectra of organic luminescent materials can be systematically manipulated by water.In this study,we successfully obtained curcumin monohydrate(Form X),a channel-type hydrate exhibiting crystallization-induced emission(CIE)at 608 nm(orange fluorescence),which contrasted with the conventional forms of aggregation-caused quenching(ACQ).Thermal treatment induced the release of hydration water,resulting in a new anhydrate(Form IV)that emitted yellow-green fluorescence with the emission peak at 575 nm.Additionally,this approach can be used to track the absorption of curcumin crystals following subcutaneous or intramuscular delivery.The hydratemediated single-crystal-to-single-crystal transition(SCSC)and its associated luminescence transition were reversible and responsive to temperature,offering a green approach for synthesizing and designing aggregation-induced-emission(AIE)-based intelligent luminescent devices for detecting air humidity or drug absorption.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.91961105,21822107,22001139,and 21827801)the Natural Science Foundation of Shandong Province(Nos.ZR2019ZD45,ZR2020ZD35,ZR2019BB058,JQ201803,and ZR2017MB061)+1 种基金the Taishan Scholar Project of Shandong Province of China(Nos.tsqn201812003 and ts20190908)the Project for Scientific Research Innovation Team of Young Scholar in Colleges and Universities of Shandong Province(No.2019KJC028).
文摘Two diphosphine-protected superatom gold selenido nanoclusters,[Au_(8)Se_(2)(dppm)4]^(2+)(SD/Au_(8)a,dppm=Ph_(2)PCH_(2)PPh_(2))and[Au_(8)Se_(2)(dppe)4]^(2+)(SD/Au_(8)b,dppe=Ph_(2)P(CH_(2))2PPh_(2)),were obtained by the reduction of[Au(SMe2)Cl]in the presence of Ph3PSe as the selenium ion releasing agents.Both can be regarded as“superatoms”with 1S^(2)configuration based on the spherical Jellium model.Despite the same metal-ligand binding motifs on the surface and the intrinsic C_(2)molecular symmetry,the configurations of Au_(8)Se_(2)kernels in them are different in terms of Au-Au bonded metallic frameworks.SD/Au_(8)a displays a heart-shaped[core+exo]type structure(Au4 tetrahedron core+two exo Au2Se units),whereas the two exo Au_(2)Se counterparts in SD/Au_(8)b are additionally locked by an obvious Au-Au bond,forming a distorted hexagonal Au6 ring with two capping AuSe units appended above and below it.Consequently,they showed different photophysical properties as reflected by their electronic absorption and emission spectra.Especially,both SD/Au_(8)a and SD/Au_(8)b exhibit blue-shifted thermochromic luminescence upon cooling from 293 to 83 K but the latter exhibits anomalous emission intensity evolution trends due to the occurrence of temperature-induced phase transition as revealed by varied-temperature crystallographic analyses.This work not only clearly illustrates the significance of ligands on tuning the kernel structure but also provides two rarely comparable examples for better understanding of the structure-property relationship of gold nanoclusters.
基金the National Natural Science Foundation of China(No.21807085)the Natural Science Foundation Research Project of Shaanxi Province(No.2023-JCYB-087)+2 种基金the Technology Innovation Leading Program of Shaanxi(No.2020QFY07-05)the Innovation Capability Support Program of Shaanxi(No.2022KJXX-88)the fund of Education Department of Shaanxi Province(Program No.Z20230071).
文摘Carbon dots(CDs)with aggregation-induced emission(AIE)have sparked significant interest in multidimensional anti-counterfeiting due to their exceptional fluorescence properties.However,the preparation of AIE CDs with multicolor solid-state fluorescence remains a formidable challenge due to its complicated construction.In the present work,a novel class of multicolor AIE CDs(M-CDs)were fabricated using selected precursor(salicylic acid,thiosalicylic acid,and 2,2'-dithiodibenzoic acid),with an eco-friendly,low-cost one-pot solvothermal method.In the dilute organic solution,M-CDs manifested blue emission,but upon aggregation in the presence of water,the red,yellow,green,and blue emissions were displayed due to the AIE effect.Structural analysis,coupled with theoretical calculations,revealed that the increase in the size of sp2 domains would lower the Eg and cause a red-shift emission wavelength.Significantly,the continuous emission of M-CDs from blue to red can be utilized as ink for multimode printing,enabling the creation of a variety of school badges and quick response codes.These findings hold promising implications for multi-information encryption applications.
基金supported by the State Scholarship Fund organized by the China Scholarship Council(CSC).
文摘Energy transfer is ubiquitous in natural and artificial lightharvesting systems,and coherent energy transfer,a highly efficient energy transfer process,has been accepted to play a vital role in such systems.However,the energy oscillation of coherent energy transfer is exceedingly difficult to capture because of its evanescence due to the interaction with a thermal environment.Here a microscopic quantum model is used to study the time evolution of electrons triggered energy transfer between coherently coupled donoracceptor molecules in scanning tunneling microscope(STM).A series of topics in the plasmonic nanocavity(PNC)coupled donor-acceptor molecules system are discussed,including resonant and nonresonant coherent energy transfer,dephasing assisted energy transfer,PNC coupling strength dependent energy transfer,Fano resonance of coherently coupled donor-acceptor molecules,and polariton-mediated energy transfer.
基金F.H.thanks National Key Research and Development Program of China (grant no.2021YFA0910100)National Natural Science Foundation of China (grant no.22035006)+5 种基金Zhejiang Provincial Natural Science Foundation of China (grant no.LD21B020001)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study (grant no.SN-ZJU-SIAS-006)the Leading Innovation Team grant from Department of Science and Technology of Zhejiang Province (grant no.2022R01005)for financial supportH.Z.thanks the National Science Foundation of China (grant no.22205197)for supportY.-Q.H.acknowledges support from the Chinese Postdoctoral Science Foundation (grant no.2022M712735)J.L.S.thanks the Robert A.Welch Foundation for chair support (grant no.F-0018).
文摘Through-space conjugation(TSC)is a noncovalently electronic interaction that is emerging as a potential complement to through-bond conjugation(TBC)-based strategies for constructing luminescent materials.However,the design of efficient luminogens based on TSC is currently challenging due to a lack of established structure-property understanding.This is particularly true in the case of luminogens displaying aggregation-induced emission(AIE)effects.In this work,three terphenyl derivatives were prepared,and their photophysical properties were systemically studied.It was found that relative to the corresponding m-and p-linked analogues,the electronic interaction of TBC is weakened while the strength of TSC is commensurately enhanced in the constitutional isomer containing an o-linked fjordtype subunit.Within this set of luminogens,the presence of a fjord-type arrangement promotes a transformation from aggregation-caused quenching to AIE.Further investigations involving congeneric quaterphenyl and pentphenyl isomers support the universality of the fjord-type unit as a framework for synthesizing AIE-active luminogens(AIEgens)with inherent TSC.This work not only provides a novel set of AIEgens but also establishes the utility of TSC in controlling the photophysical properties of nonconventional and twisted luminogens.
基金supported by the National Natural Science Foundation of China(No.U22A20617)the Natural Science Foundation of Hunan Province,China(Nos.2021JJ30664,2022JJ30559,and 2022JJ50131)Environmental Protection Research Project of Hunan Province,China(No.HBKT-2022036).
文摘In the sewage treatment process,facilitating the conversion of pollutants into value-added resources holds great potential for reducing the amount of greenhouse gas emissions and promoting economic circulation.Cyanophycin granule polypeptide(CGP),a recently discovered high value-added biopolymer present in activated sludge,has provided new avenues for the recovery of resources.However,the mechanisms that regulate CGP synthesis and the characteristics of this biopolymer in activated sludge remain unclear thus far.This study investigated the synthesis of CGP,polyhydroxyalkanoates(PHA),and alginate-like exopolysaccharides(ALE)in various microbial aggregates under different carbon sources feeding conditions.Our results showed that the CGP yields was superior that of PHA and ALE when subjected to identical carbon source feeding conditions.Furthermore,biofilm was more conducive to CGP accumulation than floc sludge.Compared with glucose and methanol,sodium acetate significantly enriched the CGP synthetase-encoding gene(cphAabundance=~17419),resulting in the highest CGP yield(average 107.1 mg/g MLSS)in both biofilm and floc sludge.This study is the first to reported the characteristic fluorescence of CGP(Ex/Em=~360/450 nm)caused by the aggregated luminescence of arginine on the side chains.Overall,this study highlights the potential application of CGP as a fluorescent material and offers insights into CGP recovery from activated sludge in wastewater treatment plants.
文摘Ion beam-induced luminescence(IBIL) experiments were performed to investigate the in situ luminescence of GaN/Al_(2)O_(3) at varying ion energies,which allowed for the measurement of defects at different depths within the material.The energies of H^(+)were set to 500 keV,640 keV and 2 MeV,the Bragg peaks of which correspond to the GaN film,GaN/Al_(2)O_(3) heterojunction and Al_(2)O_(3) substrate,respectively.A photoluminescence measurement at 250 K was also performed for comparison,during which only near band edge(NBE) and yellow band luminescence in the GaN film were observed.The evolution of the luminescence of the NBE and yellow band in the GaN film was discussed,and both exhibited a decrease with the fluence of H^(+).Additionally,the luminescence of F centers,induced by oxygen vacancies,and Cr^(3+),resulting from the ^(2)E →^(4)A_(2) radiative transition in Al_(2)O_(3),were measured using 2 MeV H^(+).The luminescence intensity of F centers increases gradually with the fluence of H^(+).The luminescence evolution of Cr^(3+)is consistent with a yellow band center,attributed to its weak intensity,and it is situated within the emission band of the yellow band in the GaN film.Our results show that IBIL measurement can effectively detect the luminescence behavior of multilayer films by adjusting the ion energy.Luminescence measurement can be excited by various techniques,but IBIL can satisfy in situ luminescence measurement,and multilayer structural materials of tens of micrometers can be measured through IBIL by adjusting the energy of the inducing ions.The evolution of defects at different layers with ion fluence can be obtained.
基金financial support from the National Natural Science Foundation of China(Nos.22175033 and 51902124).
文摘Understanding the relationship between structure and properties is critical to the development of solidstate luminescence materials with desired characteristics and performance optimization. In this work, we elaborately designed and synthesized a pair of mononuclear iridium(Ⅲ) complexes with similar structures but different degrees of cationization. [Ir2-f][2PF_(6)] with two counterions is obtained by simple Nmethylation of the ancillary ligand of [Ir1-f][PF_(6)] which is a classic cationic iridium(Ⅲ) complex. Such a tiny modification results in tremendously different optical properties in dilute solutions and powders.[Ir1-f][PF_(6)] exhibits weak light in solution but enhanced emission in solid-state as well as poly(methyl methacrylate) matrix, indicative of its aggregation-induced emission(AIE) activity. On the sharp contrary, [Ir2-f][2PF_(6)] is an aggregation-caused quenching(ACQ) emitter showing strong emission in the isolated state but nearly nonemissive in aggregation states. Benefiting from the appealing characteristics of mechanochromic luminescence and AIE behavior, [Ir1-f][PF_(6)] has been successfully applied in reversible re-writable data recording and cell imaging. These results might provide deep insights into AIE and ACQ phenomenon of iridium(Ⅲ) complexes and facilitate the development of phosphorescent materials with promising properties.
基金financial support from the Advanced Talents Incubation Program of Hebei University (521100221006)financial support from the National Natural Science Foundation of China (11974097)+2 种基金the Natural Science Foundation of Hebei Province (A2019201073)support from the National Natural Science Foundation of China (61875136)the Fundamental Research Project of Guangdong Province (2020A1515011315)
文摘Mechanoluminescent(ML)materials can directly convert external mechanical stimulation into light without the need for excitation from other forms of energy,such as light or electricity.This alluring characteristic makes ML materials potentially applicable in a wide range of areas,including dynamic imaging of force,advanced displays,information code,storage,and anti-counterfeiting encryption.However,current reproducible ML materials are restricted to sulfide-and oxide-based materials.In addition,most of the reported ML materials require pre-irradiation with ultraviolet(UV)lamps or other light sources,which seriously hinders their practical applications.Here,we report a novel ML material,MgF_(2):Mn^(2+),which emits bright red light under an external dynamic force without the need for pre-charging with UV light.The luminescence properties were systematically studied,and the piezophotonic application was demonstrated.More interestingly,unlike the well-known zinc sulfide ML complexes reported previously,a highly transparent ML film was successfully fabricated by incorporating MgF_(2):Mn^(2+)into polydimethylsiloxane(PDMS)matrices.This film is expected to find applications in advanced flexible optoelectronics such as integrated piezophotonics,artificial skin,athletic analytics in sports.
基金Supported by Science and Technology Project of Educational Commission of Shandong Province of China( J07WJ48)~~
文摘[ Objectlve] The paper was to compare the induced resistance of several chemicals on cucumber against Pseudoperonospora cubensis [ Method ] When the cucumber seedlings grew to 4-leaf stage, the second true leaf was treated with salicylic acid, oxalate, chitosan, calcium nitrate and Na2HPO4, the activity of protective enzymes in the third leaf was determined after 7 d. At the same time, inoculation test was also conducted after induced treatment, and the disease condi- tion was coumed. [ Result ] These chemical treatments promoted protective enzyme activities （POD, SOD, PAL, PPO） in different degree, improved the ultra-weak luminescence, and reduced the disease index of cucumber leaves. [ Conclusion] Five chemical treatments expressed good effects on induced resistance. Among the treatments, oxalate had the best induced effect, followed by salicylic acid, chitosan, Na2 HPO4 and calcium nitrate.
基金financially supported by the National Natural Science Foundation of China (Nos.21771113,22001132)China Postdoctoral Science Foundation (No.2019M651011)。
文摘We herein report a new lanthanide metal-organic framework(MOF) that exhibits excellent chemical stability,especially in the aqueous solution over a wide pH range from 1 to 14.In contrast to many reported lanthanide MOFs,this Tb-based MOF emits cyan fluorescence inherited from the integrated AIEactive ligand,rather than Ln3+ ions.More remarkably,its fluorescence signal features a highly selective and sensitive "turn-off" response toward CrO_(4)^(2-),Cr_(2)O_(7)^(2- )and Fe^(3+) ions,highlighted with the low detection limits down to 68.18,69.85 and 138.8 ppm,respectively.Thus,the exceptional structural stability and sensing performance render this material able to be a superior luminescent sensor for heavy metal ions in wastewater.
基金Project supported by the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.11905010)the Fundamental Research Funds for the Central Universities,China(Grant No.2018NTST04)+1 种基金the China Postdoctoral Science Foundation(Grant No.2019M650526)Guangdong Province Key Area R&D Program,China(Grant No.2019B090909002)。
文摘To understand the evolution of defects in SiC during irradiation and the influence of temperature,in situ luminescence measurements of 6H-SiC crystal samples were carried out by ion beam induced luminescence(IBIL)measurement under2 MeV H^+ at 100 K,150 K,200 K,250 K,and 300 K.A wide band(400-1000 nm)was found in the spectra at all temperatures,and the intensity of the IBIL spectra was highest at 150 K among the five temperatures.A small peak from 400 nm to 500 nm was only observed at 100 K,related with the D1 defect as a donor-acceptor pair(D-A)recombination.For further understanding the luminescent centers and their evolution,the orange band(1.79 eV)and the green band(2.14 eV)in the energy spectrum were analyzed by Gaussian decomposition,maybe due to the donor-deep defect/conduction band-deep defect transitions and Ti related bound excition,respectively.Finally,a single exponential fit showed that when the temperature exceeded 150 K,the two luminescence centers’resistance to radiation was reduced.
基金supported by the National Natural Science Foundation of China(21704065,21902073)Guangdong Basic and Applied Basic Research Foundation(2021A1515010228)the Innovation Research Foundation of Shenzhen(CYJ20190808115215125).
文摘Herein,a pair of chiral macrocyclic luminogens derived from chiral 1,1-bi(2-naphthol)(BINOL)and tetraphenylethenes(TPEs)have been prepared with high yield via intramolecular McMurry coupling,in which the preferential helicity of propeller-shaped TPE units can be tuned via choosing proper chiral BINOL tethers.The preferential chiral geometry of the macrocyclic luminogen was unambiguously confirmed by X-ray crystal crystallography and theoretical calculation,whereas the variable-temperature NMR spectra and chiral HPLC analysis further verified the intramolecular motions.These two chiral macrocyclic luminogens both exhibit obvious aggregation-induced emission behavior and mechanochromic luminescence properties.Furthermore,aggregation attenuated CD signals and circularly polarized luminescence were observed for these two chiral macrocylic luminogens in THF-water mixture and PMMA matrix.These results had paved a new approach toward constructing chiral aggregation-induced emission luminogens(AIEgens)and their structural engineering.
