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
Herein,we report a new metal-organic framework with an AIE ligand (H_(4)TCPP=2,3,5,6-tetra-(4-carboxyphenyl)pyrazine) and Mg^(2+) ions,that is,[Mg_(2)(H_(2)O)_(4)TCPP]·DMF·5CH_(3)CN (Mg-TCPP,TCPP=tetra-(4-ca...Herein,we report a new metal-organic framework with an AIE ligand (H_(4)TCPP=2,3,5,6-tetra-(4-carboxyphenyl)pyrazine) and Mg^(2+) ions,that is,[Mg_(2)(H_(2)O)_(4)TCPP]·DMF·5CH_(3)CN (Mg-TCPP,TCPP=tetra-(4-carboxyphenyl)pyrazine) for detection of nitroaromatic explosives.Due to the coordination effect and restricted intramolecular rotation,Mg-TCPP exhibits bright blue light.As a fluorescent sensor,Mg-TCPP exhibits high selectivity and sensitivity for sensing 2,4,6-trinitrophenol (TNP) by quenching behaviors with the Stern-Volmer quenching constant (K_(SV)) of 3.63×10^(5)L/mol and achieves the low limit of detection of 25.6 ppb,which is beyond most of the previously reported fluorescent materials.Notably,the portable Mg-TCPP films are prepared and it can be used for rapid and sensitive TNP detection in a variety of environments including organic solvent and aqueous solution.Moreover,TNP vapor can be detected within 3 min by naked eye and the film could be regenerated under simple solvent cleaning.展开更多
Luminescent polymers have garnered considerable research attention for their excellent properties and wide range of applications in multi-responsive materials,bioimaging,and photoelectric devices.Thereout,various modu...Luminescent polymers have garnered considerable research attention for their excellent properties and wide range of applications in multi-responsive materials,bioimaging,and photoelectric devices.Thereout,various modulations of polymer structure are often the main approach to obtaining materials with different luminescent colors and functions.However,polymers with biodegradability,tunable color,and efficient emission simultaneously remain a challenge.Herein,we report a feasible strategy to achieve degradable and highly emissive polymers by exquisite combination and interplay of aggregation-induced emission(AIE)unit and environmental-friendly epoxide/CO_(2)copolymerization.A series of polycarbonates P-TEP_(x)CN_(y)(x=0,1,2,4,30,120;y=0,1)were prepared,with emission color changed from blue to yellow by controlling the proportion of two designed AIE-active monomers.Among them,Using P-TCN as emitting layer,high performance white light-emitting diode(WLED)device with an external quantum efficiency(EQE)of 26.09%and CIE coordinates of(0.32,0.32)was achieved.In addition,the designed polymers can be used as selective sensors for nitroaromatic compounds in their nanoaggregate states.展开更多
Photon emission (PE) and light-induced photon emission(LPE) of intact brains isolated from chick embryos have been measured by using the single photon counting device. Experimental results showed that the intensi-ty l...Photon emission (PE) and light-induced photon emission(LPE) of intact brains isolated from chick embryos have been measured by using the single photon counting device. Experimental results showed that the intensi-ty level of photon emission was detected to be higher from intact brain than from the medium in which the brain was immerged during measuring, and the emission intensity was related to the developmental stages, the healthy situation of the measured embryos, and the freshness of isolated brains as well. After white light illumination, a short-life de-layed emission from intact brains was observed, and its relaxation behavior followed a hyperbolic rather than an expo-nential law. According to the hypothesis of biophoton emission originating from a delocalized coherent electromagnetic field and Frohlich's idea of coherent long-range interactions in biological systems, discussions were made on the signifi-cance of photon emission in studying cell communication, biological regulation, living system's relevance to its environ-ment, and also on the relations between the detected photon emission and the coherent electromagnetic field. The de-tected photon emission should be comprehended in the manner of the interactions between the intrinsic fields within the living systems and their environmental external fields.展开更多
Understanding the physical mechanisms governing aggregation-induced-emission(AIE)and aggrega-tion-caused-quenching plays a vital role in developing functional AIE materials.In this work,tetraphenylethene(TPE,a classic...Understanding the physical mechanisms governing aggregation-induced-emission(AIE)and aggrega-tion-caused-quenching plays a vital role in developing functional AIE materials.In this work,tetraphenylethene(TPE,a classical AiEgen)and naphthalimide(NI,a popular fluorophore with ACQ characteristics)were connected through non-conjugated linkages and conjugated linkages.We showed that the nonconjugated-linkage of TPE to NI fragments leads to substantial PET in molecular aggregates and ACQ.In con trast,the conjugated conn ection between TPE and NI moieties results in the AIE phenomenon by suppressing twisted intramolecular charge transfer.This work provides an important guideline for the rational design of AIE materials.展开更多
Organic luminescent materials are very sensitive to external stimuli,such as pressure,temperature,and electric field.The luminescent properties of some organic luminescent materials significantly change under high pre...Organic luminescent materials are very sensitive to external stimuli,such as pressure,temperature,and electric field.The luminescent properties of some organic luminescent materials significantly change under high pressure.Some materials may show luminescence discoloration,whereas some may exhibit luminescence enhancement.These properties have many potential applications in anticounterfeiting,force sensor,data recording and storage,and luminescent devices,thereby greatly attracting the attention of scientists.In this review,the progress of research on these materials at high pressure in recent years is summarized.展开更多
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supported by the National Natural Science Foundation of China(No.22175033)Science and Technology Development Plan of Jilin Province(Nos.YDZJ202101ZYTS063,20210508022RQ)Research Foundation of Education Department of Shaanxi Province(No.18JS009)。
文摘Herein,we report a new metal-organic framework with an AIE ligand (H_(4)TCPP=2,3,5,6-tetra-(4-carboxyphenyl)pyrazine) and Mg^(2+) ions,that is,[Mg_(2)(H_(2)O)_(4)TCPP]·DMF·5CH_(3)CN (Mg-TCPP,TCPP=tetra-(4-carboxyphenyl)pyrazine) for detection of nitroaromatic explosives.Due to the coordination effect and restricted intramolecular rotation,Mg-TCPP exhibits bright blue light.As a fluorescent sensor,Mg-TCPP exhibits high selectivity and sensitivity for sensing 2,4,6-trinitrophenol (TNP) by quenching behaviors with the Stern-Volmer quenching constant (K_(SV)) of 3.63×10^(5)L/mol and achieves the low limit of detection of 25.6 ppb,which is beyond most of the previously reported fluorescent materials.Notably,the portable Mg-TCPP films are prepared and it can be used for rapid and sensitive TNP detection in a variety of environments including organic solvent and aqueous solution.Moreover,TNP vapor can be detected within 3 min by naked eye and the film could be regenerated under simple solvent cleaning.
基金supported by the National Natural Science Foundation of China(No.22175033)the Scientific and Technological Innovation Team of Shanxi Province(No.2022TD-36).
文摘Luminescent polymers have garnered considerable research attention for their excellent properties and wide range of applications in multi-responsive materials,bioimaging,and photoelectric devices.Thereout,various modulations of polymer structure are often the main approach to obtaining materials with different luminescent colors and functions.However,polymers with biodegradability,tunable color,and efficient emission simultaneously remain a challenge.Herein,we report a feasible strategy to achieve degradable and highly emissive polymers by exquisite combination and interplay of aggregation-induced emission(AIE)unit and environmental-friendly epoxide/CO_(2)copolymerization.A series of polycarbonates P-TEP_(x)CN_(y)(x=0,1,2,4,30,120;y=0,1)were prepared,with emission color changed from blue to yellow by controlling the proportion of two designed AIE-active monomers.Among them,Using P-TCN as emitting layer,high performance white light-emitting diode(WLED)device with an external quantum efficiency(EQE)of 26.09%and CIE coordinates of(0.32,0.32)was achieved.In addition,the designed polymers can be used as selective sensors for nitroaromatic compounds in their nanoaggregate states.
基金Project supported by the National Natural Science Foundation of China.
文摘Photon emission (PE) and light-induced photon emission(LPE) of intact brains isolated from chick embryos have been measured by using the single photon counting device. Experimental results showed that the intensi-ty level of photon emission was detected to be higher from intact brain than from the medium in which the brain was immerged during measuring, and the emission intensity was related to the developmental stages, the healthy situation of the measured embryos, and the freshness of isolated brains as well. After white light illumination, a short-life de-layed emission from intact brains was observed, and its relaxation behavior followed a hyperbolic rather than an expo-nential law. According to the hypothesis of biophoton emission originating from a delocalized coherent electromagnetic field and Frohlich's idea of coherent long-range interactions in biological systems, discussions were made on the signifi-cance of photon emission in studying cell communication, biological regulation, living system's relevance to its environ-ment, and also on the relations between the detected photon emission and the coherent electromagnetic field. The de-tected photon emission should be comprehended in the manner of the interactions between the intrinsic fields within the living systems and their environmental external fields.
基金financial support from the National Natural Science Foundation of China (Nos.21676113,21772054)Distinguished Young Scholar Program of Hubei Province (No. 2018CFA079)+5 种基金the 111 Project B17019the Scholar Support Program of CCNU (No.0900-31101090002)the Excellent Doctoral Dissertation Cultivation Grant of CCNU from the colleges’ basic research and operation grant (MOE,No.2019YBZZ029)supported by Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules (No. KLSAOFM2012),Hubei University,Chinasupported by excellent doctorial dissertation cultivation grant of CCNU from the colleges’ basic research and operation of MOE (No.2019YBZZ029)A*STAR under its Advanced Manufacturing and Engineering Program (No.A2083c0051)
文摘Understanding the physical mechanisms governing aggregation-induced-emission(AIE)and aggrega-tion-caused-quenching plays a vital role in developing functional AIE materials.In this work,tetraphenylethene(TPE,a classical AiEgen)and naphthalimide(NI,a popular fluorophore with ACQ characteristics)were connected through non-conjugated linkages and conjugated linkages.We showed that the nonconjugated-linkage of TPE to NI fragments leads to substantial PET in molecular aggregates and ACQ.In con trast,the conjugated conn ection between TPE and NI moieties results in the AIE phenomenon by suppressing twisted intramolecular charge transfer.This work provides an important guideline for the rational design of AIE materials.
基金supported by the National Natural Science Foundation of China(NSFC,Nos.21725304 and 11774120)the Chang Jiang Scholars Program of China(No.T2016051)the Fundamental Research Funds for the Central Universities
文摘Organic luminescent materials are very sensitive to external stimuli,such as pressure,temperature,and electric field.The luminescent properties of some organic luminescent materials significantly change under high pressure.Some materials may show luminescence discoloration,whereas some may exhibit luminescence enhancement.These properties have many potential applications in anticounterfeiting,force sensor,data recording and storage,and luminescent devices,thereby greatly attracting the attention of scientists.In this review,the progress of research on these materials at high pressure in recent years is summarized.
