Journal articles: 'Luminescence lifetime'

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Kang, Jie, Ai Ling Wang, Yan Rong Qu, Hai Bin Chu, and Yong Liang Zhao. "Preparation and Luminescent Property of Eu_xY_y(TPTZ)₂(POA)₆ Complexes." Advanced Materials Research 1078 (December 2014): 118–21. http://dx.doi.org/10.4028/www.scientific.net/amr.1078.118.

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Using anion ligand phenoxyacetic acid (HPOA) and neutral ligand 2,4,6-tri(2-pyridyl)-s-triazine (TPTZ), a series of novel europium complexes EuxYy(TPTZ)2(POA)6·6H2O. The luminescence spectra, luminescence lifetimes and emission quantum efficiencies of the complexes were studied. The results show that doping appropriate amount of Y3+ can significantly increase the luminescence intensities, prolong the luminescent lifetime and improve the emission quantum efficiencies.

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de la Torre, Angel, Santiago Medina-Rodríguez, Jose C. Segura, and Jorge F. Fernández-Sánchez. "Self-Referenced Multifrequency Phase-Resolved Luminescence Spectroscopy." Sensors 20, no. 19 (September 24, 2020): 5482. http://dx.doi.org/10.3390/s20195482.

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Phase-resolved luminescence chemical sensors provide the analyte determination based on the estimation of the luminescence lifetime. The lifetime is estimated from an analysis of the amplitudes and/or phases of the excitation and emission signals at one or several modulation frequencies. This requires recording both the excitation signal (used to modulate the light source) and the emission signal (obtained from an optical transducer illuminated by the luminescent sensing phase). The excitation signal is conventionally used as reference, in order to obtain the modulation factor (the ratio between the emission and the excitation amplitudes) and/or the phase shift (the difference between the emission and the excitation phases) at each modulation frequency, which are used to estimate the luminescence lifetime. In this manuscript, we propose a new method providing the luminescence lifetimes (based either on amplitudes or phases) using only the emission signal (i.e., omitting the excitation signal in the procedure). We demonstrate that the luminescence lifetime can be derived from the emission signal when it contains at least two harmonics, because in this case the amplitude and phase of one of the harmonics can be used as reference. We present the theoretical formulation as well as an example of application to an oxygen measuring system. The proposed self-referenced lifetime estimation provides two practical advantages for luminescence chemical sensors. On one hand, it simplifies the instrument architecture, since only one analog-to-digital converter (for the emission signal) is necessary. On the other hand, the self-referenced estimation of the lifetime improves the robustness against degradation of the sensing phase or variations in the optical coupling, which reduces the recalibration requirements when the lifetimes are based on amplitudes.

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Waters, P. Dean, and David H. Burns. "Optimized Gated Detection for Lifetime Measurement over a Wide Range of Single Exponential Decays." Applied Spectroscopy 47, no. 1 (January 1993): 111–15. http://dx.doi.org/10.1366/0003702934048622.

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Optimal estimation parameters are determined for the rapid lifetime determination technique (RLD) of fitting an exponential model to luminescence decay data that exhibit a wide range of lifetimes. Optimization of the lifetime estimate by this technique depends on only two parameters—period of integration and separation between the periods of integration. Luminescence quenching experiments produce a range of decay lifetimes. Selection of a fixed set of measuring parameters to determine lifetime throughout the entire range can simplify instrumentation and result in enhanced computation speed. The measuring parameters must be optimized to yield the best estimation of each lifetime in the range. The errors in measured lifetime for the RLD technique are investigated for a wide range of luminescence decays. Optimal separation and periods of integration for the modified RLD technique are found by modeling a set of simulated decay data with different lifetimes. Results from the simulation are then compared to similar measurements of oxygen-quenched luminescence decay. Agreement between simulation and quenching data is good.

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Lis, Stefan, Slawomir But, Andrzej M. Klonkowski, and Beata Grobelna. "Spectroscopic studies of Ln(III) complexes with polyoxometalates in solids, and aqueous and non-aqueous solutions." International Journal of Photoenergy 5, no. 4 (2003): 233–38. http://dx.doi.org/10.1155/s1110662x03000370.

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Chosen polyoxometalate (POM) anions and their lanthanide(III) complexes, LnPOM, have been synthesized and spectroscopically characterized in solid state, aqueous and non-aqueous solutions. POMs, such as Keggin's, Dawson's and Anderson's type,Na9EuW10O36, compositions that function as inorganic cryptands ([(Na)P5W30O110]14−-Preyssler anion, and [(Na)As4W40O140]27−), containing inorganic(Na+,K+,NH4+)or organic (tetrabutylammonium,NBu4+) counter cations were obtained and their Ln(III) complexes (sandwiched and encapsulated) studied. The synthesized compounds were identified using elemental and thermogravimetric analysis, UV-Vis spectrophotometry and FTIR spectroscopy. The complexation studies were carried out with the use Nd(III) and Er(III) optical absorption and Eu(III) luminescence spectroscopy. Luminescence characterization, including results of intensity, quantum yields and luminescence lifetimes of EuPOM complexes in aqueous, non-aqueous solutions (DMF, DMSO, acetonitryle) and solid are discussed. Based on luminescence lifetime measurements of the Eu(III) ion the hydration numbers of its sandwiched (efficient emitters) and encrypted complexes have been determined and quenching effect discussed. The Eu(III) complexes entrapped in a xerogel matrix have been studied as luminescent materials. Luminescence intensity, lifetime and quantum yield of the EuPOM materials and their photochemical stability, during continuous UV irradiation, were tested.

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Lu, Kailei, Yingxin Yi, Li Xu, Xianhao Sun, Lu Liu, and Hanyang Li. "Temperature-Independent Lifetime and Thermometer Operated in a Biological Window of Upconverting NaErF4 Nanocrystals." Nanomaterials 10, no. 1 (December 20, 2019): 24. http://dx.doi.org/10.3390/nano10010024.

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Lifetime of lanthanide luminescence basically decreases with increasing the ambient temperature. In this work, we developed NaErF4 core–shell nanocrystals with compensation of the lifetime variation with temperature. Upconversion lifetime of various emissions remains substantially unchanged as increasing the ambient temperature, upon 980/1530 nm excitation. The concentrated dopants, leading to extremely strong interactions between them, are responsible for the unique temperature-independent lifetime. Besides, upconversion mechanisms of NaErF4 core-only and core–shell nanocrystals under 980 and 1530 nm excitations were comparatively investigated. On the basis of luminescent ratiometric method, we demonstrated the optical thermometry using non-thermally coupled 4F9/2 and 4I9/2 emissions upon 1530 nm excitation, favoring the temperature monitoring in vivo due to both excitation and emissions fall in the biological window. The formed NaErF4 core–shell nanocrystals with ultra-small particle size, highly efficient upconversion luminescence, unique temperature-independent lifetimes, and thermometry operated in a biological window, are versatile in applications such as anti-counterfeiting, time-domain manipulation, and biological thermal probes.

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Gonzalez-Garcia, M. Carmen, Pilar Herrero-Foncubierta, Emilio Garcia-Fernandez, and Angel Orte. "Building Accurate Intracellular Polarity Maps through Multiparametric Microscopy." Methods and Protocols 3, no. 4 (November 11, 2020): 78. http://dx.doi.org/10.3390/mps3040078.

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The precise knowledge of intracellular polarity, a physiological parameter that involves complex and intertwined intracellular mechanisms, may be relevant in the study of important diseases like cancer or Alzheimer’s. In this technical note, we illustrate our recently developed, accurate method for obtaining intracellular polarity maps employing potent fluorescence microscopy techniques. Our method is based on the selection of appropriate luminescent probes, in which several emission properties vary with microenvironment polarity, specifically spectral shifts and luminescence lifetime. A multilinear calibration is performed, correlating polarity vs. spectral shift vs. luminescence lifetime, to generate a powerful and error-free 3D space for reliable interpolation of microscopy data. Multidimensional luminescence microscopy is then used to obtain simultaneously spectral shift and luminescence lifetime images, which are then interpolated in the 3D calibration space, resulting in accurate, quantitative polarity maps.

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Kühl, Michael, Lars F. Rickelt, and Roland Thar. "Combined Imaging of Bacteria and Oxygen in Biofilms." Applied and Environmental Microbiology 73, no. 19 (August 17, 2007): 6289–95. http://dx.doi.org/10.1128/aem.01574-07.

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ABSTRACT Transparent sensors for microscopic O2 imaging were developed by spin coating an ultrathin (<1- to 2-μm) layer of a luminescent O2 indicator onto coverslips. The sensors showed (i) an ideal Stern-Volmer quenching behavior of the luminescence lifetime towards O2 levels, (ii) homogeneous measuring characteristics over the sensor surface, and (iii) a linear decline of luminescence lifetime with increasing temperature. When a batch of such coverslip sensors has been characterized, their use is thus essentially calibration free at a known temperature. The sensors are easy to use in flow chambers and other growth devices used in microbiology. We present the first application for combined imaging of O2 and bacteria in a biofilm flow chamber mounted on a microscope equipped with a spinning-disk confocal unit and a luminescence lifetime camera system.

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Egami, Yasuhiro, Yuya Yamazaki, Naoto Hori, Yosuke Sugioka, and Kazuyuki Nakakita. "Investigation of Factors Causing Nonuniformity in Luminescence Lifetime of Fast-Responding Pressure-Sensitive Paints." Sensors 21, no. 18 (September 10, 2021): 6076. http://dx.doi.org/10.3390/s21186076.

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Factors that cause nonuniformity in the luminescence lifetime of pressure-sensitive paints (PSPs) were investigated. The lifetime imaging method of PSP does not theoretically require wind-off reference images. Therefore, it can improve measurement accuracy because it can eliminate errors caused by the deformation or movement of the model during the measurement. However, it is reported that the luminescence lifetime of PSP is not uniform on the model, even under uniform conditions of pressure and temperature. Therefore, reference images are used to compensate for the nonuniformity of the luminescence lifetime, which significantly diminishes the advantages of the lifetime imaging method. In particular, fast-responding PSPs show considerable variation in luminescence lifetime compared to conventional polymer-based PSPs. Therefore, this study investigated and discussed the factors causing the nonuniformity of the luminescence lifetime, such as the luminophore solvent, luminophore concentrations, binder thickness, and spraying conditions. The results obtained suggest that the nonuniformity of the luminophore distribution in the binder caused by the various factors mentioned above during the coating process is closely related to the nonuniformity of the luminescence lifetime. For example, when the thickness of the binder became thinner than 8 μm, the fast-responding PSPs showed a tendency to vary significantly in the luminescence lifetime. In addition, it was found that the luminescence lifetime of fast-responding PSP could be changed in the depth direction of the binder depending on the coating conditions. Therefore, it is important to distribute the luminophore uniformly in the binder layer to create PSPs with a more uniform luminescence lifetime distribution.

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Jung, Euo Chang, Yongheum Jo, Tae-Hyeong Kim, Hee-Kyung Kim, Hye-Ryun Cho, Wansik Cha, Min Hoon Baik, and Jong-Il Yun. "Surface Coverage- and Excitation Laser Wavelength-Dependent Luminescence Properties of U(VI) Species Adsorbed on Amorphous SiO2." Minerals 12, no. 2 (February 10, 2022): 230. http://dx.doi.org/10.3390/min12020230.

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Time-resolved luminescence spectroscopy is usefully used to identify U(VI) surface species adsorbed on SiO2. However, the cause of the inconsistent luminescence lifetimes and spectral shapes reported previously remains undetermined. In this study, the U(VI) surface coverage (Γ) and excitation laser wavelength (λex) were examined as the predominant factors governing the luminescence properties of U(VI) surface species. At neutral pH, the luminescence lifetimes of U(VI) surface species increased with decreasing Γ. In the low-Γ region, where a relatively large number of adjacent surface sites are involved in the formation of multidentate surface complexes, the displacement of more number of coordinated water molecules in the equatorial plane of U(VI) results in a longer lifetime. The pH-dependent luminescence lifetimes of U(VI) surface species at the same U(VI) to SiO2 concentration ratio in the pH range of 4.5–7.5 also explain the effect of the surface binding sites on the luminescence lifetime. The time-resolved luminescence properties of the U(VI) surface species were also investigated at different excitation wavelengths. Continued irradiation of the SiO2 surface with a UV laser beam at λex = 266 nm considerably reduced the luminescence intensities of the U(VI) surface species. The higher the laser pulse energy, the greater the decrease in luminescence intensity. Laser-induced thermal desorption (LITD) of U(VI) surface species is suggested to be the origin of the decrease in luminescence intensity. LITD effects were not observed at λex = 355 and 422 nm, even at high laser pulse energies.

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Zhao, Zhihuan, Yao Wang, Haoyang Jiang, Jixian Liu, Linjun Huang, Yanna Zhang, Yanqi Wang, Laurence A. Belfiore, and Jianguo Tang. "Optical Features of Lanthanide Luminescent Hydrogel Based on Polyethylene Glycol with Silica Nanoparticles." Science of Advanced Materials 13, no. 1 (January 1, 2021): 123–30. http://dx.doi.org/10.1166/sam.2021.3850.

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Inorganic/polymer hybrid hydrogels generally exhibit excellent mechanical properties, while extra function include luminescence are extremely explored due to the further application in sensors and optoelectronic devices. Herein, we report the rare-earth (RE) complex/silica nanoparticles (SNs) luminescent hybrid polyethylene glycol (PEG) hydrogels showing stable luminescence. The hybrid hydrogels coordinated with RE (Eu3+) complex are fabricated via a convenient in situ photocrosslinked procedure. The coordination polymers showed red luminescent color under the 365 nm UV irradiation. Furthermore, the hybrid hydrogel exhibited long luminescence lifetime. These properties of hybrid luminescent hydrogel gave rise to a great improvement in the potential applications as a soft material.

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Pisarska, Joanna, Wojciech A. Pisarski, Radosław Lisiecki, and Witold Ryba-Romanowski. "Phonon Sideband Analysis and Near-Infrared Emission in Heavy Metal Oxide Glasses." Materials 14, no. 1 (December 30, 2020): 121. http://dx.doi.org/10.3390/ma14010121.

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In this work, spectroscopic properties of europium and erbium ions in heavy metal oxide glasses have been studied. The phonon energy of the glass host was determined based on Eu3+ excitation spectra measurements. Near-IR emission spectra at 1550 nm related to 4I13/2 → 4I15/2 transition of erbium in heavy metal glasses were examined with special regards to luminescence bandwidth and measured lifetime. In particular, correlation between phonon energy and the measured lifetime 4I13/2 (Er3+) was proposed. The luminescence lifetime for the 4I13/2 upper laser state of erbium decreases with increasing phonon energy in glass matrices. Completely different results were obtained glass samples with europium ions, where the 5D0 lifetime increases with increasing phonon energy. Our investigations suggest that the values of measured 5D0 lifetime equal to radiative lifetimes for all heavy metal oxide glasses.

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Beltramini, M., G. M. Giacometti, B. Salvato, G. Giacometti, K. Münger, and K. Lerch. "Luminescence emission from Neurospora copper metallothionein. Time-resolved studies." Biochemical Journal 260, no. 1 (May 15, 1989): 189–93. http://dx.doi.org/10.1042/bj2600189.

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The luminescence lifetime of Cu-metallothionein from the fungus Neurospora crassa has been studied by the frequency-domain emission technique. Lifetimes of 10.3 and 3.4 microseconds have been found for the protein in the absence and in the presence of oxygen respectively. Binding of Hg(II) results in a quenching of the luminescence correlated to the shortening of lifetime to 0.3-0.4 microsecond. No quenching by oxygen is found for the Hg(II)-Cu-metallothionein adduct. By analogy to model compounds, luminescence emission is attributed to a triplet excited state of a Cu(I)-to-sulphur charge-transfer complex. The comparison of bimolecular quenching constants for O2 and acrylamide indicates a highly compact structure of the protein.

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Osborne, Shani A. M., and Zoe Pikramenou. "Highly luminescent gold nanoparticles: effect of ruthenium distance for nanoprobes with enhanced lifetimes." Faraday Discussions 185 (2015): 219–31. http://dx.doi.org/10.1039/c5fd00108k.

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The photophysical properties of gold nanoparticles, AuNPs, with sizes of 13, 50 and 100 nm in diameter, coated with surface-active ruthenium complexes have been studied to investigate the effect of the distance of the ruthenium luminescent centre from the gold surface. Luminescence lifetimes of the three ruthenium probes, RuS1, RuS6 and RuS12, with different length spacer units between the surface active groups and the ruthenium centre were taken. The metal complexes were attached to AuNP13, AuNP50 and AuNP100via thiol groups using a method of precoating the nanoparticles with a fluorinated surfactant. The luminescence lifetime of the longer spacer unit complex, RuS12, was enhanced by 70% upon attachment to the AuNP when compared to the increase of the short and medium linker unit complexes, RuS1 (20%) and RuS6 (40%) respectively. The effect of the surfactant in the lifetime increase of the ruthenium coated AuNPs was shown to be larger for the medium spacer probe, RuS6. There was no effect of the change of the size of the AuNPs from 13 to 50 or 100 nm.

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Kuznetsova, Vera, Anton Tkach, Sergei Cherevkov, Anastasiia Sokolova, Yulia Gromova, Viktoria Osipova, Mikhail Baranov, Valery Ugolkov, Anatoly Fedorov, and Alexander Baranov. "Spectral-Time Multiplexing in FRET Complexes of AgInS2/ZnS Quantum Dot and Organic Dyes." Nanomaterials 10, no. 8 (August 10, 2020): 1569. http://dx.doi.org/10.3390/nano10081569.

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Nowadays, multiplex analysis is very popular, since it allows to detect a large number of biomarkers simultaneously. Traditional multiplex analysis is usually based on changes of photoluminescence (PL) intensity and/or PL band spectral positions in the presence of analytes. Using PL lifetime as an additional parameter might increase the efficiency of multiplex methods. Quantum dots (QDs) can be used as luminescent markers for multiplex analysis. Ternary in-based QDs are a great alternative to the traditional Cd-based one. Ternary QDs possess all advantages of traditional QDs, including tunable photoluminescence in visible range. At the same time ternary QDs do not have Cd-toxicity, and moreover they possess long spectral dependent lifetimes. This allows the use of ternary QDs as a donor for time-resolved multiplex sensing based on Förster resonance energy transfer (FRET). In the present work, we implemented FRET from AgInS2/ZnS ternary QDs to cyanine dyes absorbing in different spectral regions of QD luminescence with different lifetimes. As the result, FRET-induced luminescence of dyes differed not only in wavelengths but also in lifetimes of luminescence, which can be used for time-resolved multiplex analysis in biology and medicine.

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Yamshchikov, V. M. "Influence of a Scattering Medium Consisting of Potassium Atoms on the Luminescent Signal Decay Time: Theoretical Investigation by Monte Carlo Method." Herald of the Bauman Moscow State Technical University. Series Natural Sciences, no. 3 (102) (June 2022): 69–85. http://dx.doi.org/10.18698/1812-3368-2022-3-69-85.

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The study solves the problem of the luminescent photons propagation in a resonantly absorbing medium consisting of atoms of the studied substance and a buffer inert gas. The Monte Carlo method was used in numerical experiments carried out to simulate real processes that occur in a chamber designed to determine the lifetime of an individual atom in an excited state by the method of measuring the luminescence intensity decay time. Findings of the research show that when luminescent photons are repeatedly scattered (scattering means the process of absorption and re-emission of a photon by an atom) in a medium, the luminescence decay time noticeably increases, reaching a value greater than the average lifetime of an individual atom in an excited state. The reflection of photons from the walls that make up the chamber can lead to errors in measuring the lifetime. The process of luminescence decay is studied theoretically for various detunings of the laser frequency from the resonant transition frequency. A three-level model of the atom and a model of complete frequency redistribution were applied. The study describes an algorithm based on the Monte Carlo method, which is used to model the three-level population kinetics, laser radiation transfer, radiation trapping, and frequency redistribution

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Suzuki, Hitoshi, and Hiroshi Mizushima. "ICCDcamera based Luminescence Lifetime Imaging." Journal of the Visualization Society of Japan 21, no. 1Supplement (2001): 321–24. http://dx.doi.org/10.3154/jvs.21.1supplement_321.

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Liaugaudas, Gediminas, Alan T. Collins, Klaus Suhling, Gordon Davies, and Rainer Heintzmann. "Luminescence-lifetime mapping in diamond." Journal of Physics: Condensed Matter 21, no. 36 (August 19, 2009): 364210. http://dx.doi.org/10.1088/0953-8984/21/36/364210.

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Zhang, Ning, and Shiqing Man. "Luminescent Properties of a Novel Mn²⁺ doped 3CaO-CaF₂-2SiO₂ Glasses." Journal of Physics: Conference Series 2076, no. 1 (November 1, 2021): 012048. http://dx.doi.org/10.1088/1742-6596/2076/1/012048.

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Abstract The transition metal Mn2+ ions doped materials have been widely reported for the luminescent properties for its broad emission band from green to red due to the spin-forbidden 4T1→6A1 transitions. To investigate the luminescent properties of Mn2+ ions in cuspidine glass, the 3CaO-CaF2-2SiO2 glasses doped with different Mn2+ concentration were prepared with traditional melt-quenching method. The luminescence emission spectra, excitation spectra and luminescence decay curves were recorded and analyzed. The tunable broadband emission from orange to red was obtained. The luminescence intensity and lifetime of Mn2+: 4T1 level showed different quenching points with the increasing of Mn2+ concentration. All these results indicate that Mn2+ doped 3CaO-CaF2-2SiO2 glass could be applied as light conversion material for solid-state lighting applications.

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Wang, Wanhe, Zhifeng Mao, Modi Wang, Li-Juan Liu, Daniel W. J. Kwong, Chung-Hang Leung, and Dik-Lung Ma. "A long lifetime luminescent iridium(iii) complex chemosensor for the selective switch-on detection of Al3+ ions." Chemical Communications 52, no. 18 (2016): 3611–14. http://dx.doi.org/10.1039/c5cc10383e.

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A novel luminescent cyclometalated iridium(iii) complex 1 was synthesized and employed as a chemosensor for the detection of Al³⁺ ions. 1 displays a long lifetime luminescence that allow 1 to detect Al³⁺ ions in strong fluorescence media.

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Ren, Jinjun, Jianrong Qiu, Danping Chen, Chen Wang, Xiongwei Jiang, and Congshan Zhu. "Infrared luminescence properties of bismuth-doped barium silicate glasses." Journal of Materials Research 22, no. 7 (July 2007): 1954–58. http://dx.doi.org/10.1557/jmr.2007.0245.

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Infrared (IR) luminescence covering 1.1 to ∼1.6 μm wavelength region was observed from bismuth-doped barium silicate glasses, excited by a laser diode at 808 nm wavelength region, at room temperature. The peak of the IR luminescence appears at 1325 nm. A full width half-maximum (FWHM) and the lifetime of the fluorescence is more than 200 nm and 400 μs, respectively. The fluorescence intensity increases with Al2O3 content, but decreases with BaO content. We suggest that the IR luminescence should be ascribed to the low valence state of bismuth Bi2+ or Bi+, and Al3+ ions play an indirect dispersing role for the infrared luminescent centers.

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Gao, Dangli, Peng Wang, Feng Gao, William Nguyen, and Wei Chen. "Tuning Multicolor Emission of Manganese-Activated Gallogermanate Nanophosphors by Regulating Mn Ions Occupying Sites for Multiple Anti-Counterfeiting Application." Nanomaterials 12, no. 12 (June 13, 2022): 2029. http://dx.doi.org/10.3390/nano12122029.

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The ability to manipulate the luminescent color, intensity and long lifetime of nanophosphors is important for anti-counterfeiting applications. Unfortunately, persistent luminescence materials with multimode luminescent features have rarely been reported, even though they are expected to be highly desirable in sophisticated anti-counterfeiting. Here, the luminescence properties of Zn3Ga2GeO8:Mn phosphors were tuned by using different preparation approaches, including a hydrothermal method and solid-state reaction approach combining with non-equivalent ion doping strategy. As a result, Mn-activated Zn3Ga2GeO8 phosphors synthesized by a hydrothermal method demonstrate an enhanced red photoluminescence at 701 nm and a strong green luminescence with persistent luminescence and photostimulated luminescence at 540 nm. While Mn-activated Zn3Ga2GeO8 phosphors synthesized by solid-state reactions combined with a hetero-valent doping approach only exhibit an enhanced single-band red emission. Keeping the synthetic method unchanged, the substitution of hetero-valent dopant ion Li+ into different sites is valid for spectral fine-tuning. A spectral tuning mechanism is also proposed. Mn-activated Zn3Ga2GeO8 phosphors synthesized by a hydrothermal approach with multimodal luminescence is especially suitable for multiple anti-counterfeiting, multicolor display and other potential applications.

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Knyazev, Andrey A., Aleksandr S. Krupin, and Yuriy G. Galyametdinov. "Composites Based on Polylactide Doped with Amorphous Europium(III) Complex as Perspective Thermosensitive Luminescent Materials." Inorganics 10, no. 12 (November 30, 2022): 232. http://dx.doi.org/10.3390/inorganics10120232.

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This work reports fabrication of polylactide (PLA) films doped with various additives of an amorphous Eu(III) complex. We study the temperature behavior of the luminescence intensity and lifetime of the PLA-Eu(III) composites in the range of 298–353 K and investigate the mechanism of luminescence temperature quenching. The peak relative sensitivity of the films reaches 20.1 %×K−1 and exceeds the respective characteristics of all known lanthanide-containing thermosensors designed for the range of physiological temperatures. The produced films can be potential novel materials for luminescent thermosensors.

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Levin, E. I., S. Marianer, B. I. Shkolvskii, and H. Fritzsche. "Luminescence lifetime distribution in amorphous semiconductors." Journal of Non-Crystalline Solids 137-138 (January 1991): 559–62. http://dx.doi.org/10.1016/s0022-3093(05)80179-6.

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Bas, Alin-Ciprian, Xavier Thompson, Lionel Salmon, Christophe Thibault, Gábor Molnár, Oleg Palamarciuc, Lucie Routaboul, and Azzedine Bousseksou. "Bilayer Thin Films That Combine Luminescent and Spin Crossover Properties for an Efficient and Reversible Fluorescence Switching." Magnetochemistry 5, no. 2 (May 1, 2019): 28. http://dx.doi.org/10.3390/magnetochemistry5020028.

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We report on the vacuum thermal deposition of bilayer thin films of the luminescent complex Ir(ppy)3, tris[2-phenylpyridinato-C2,N]iridium(III), and the spin crossover complex [Fe(HB(tz)3)2], bis[hydrotris(1,2,4-triazol-1-yl)borate]iron(II). Switching the spin state of iron ions from the low spin to the high spin state around 337 K leads to a reversible jump of the luminescence intensity, while the spectrum shape and the luminescence lifetime remain unchanged. The luminescence modulation occurs due to the different UV light absorption properties of the iron complex in the two spin states and its magnitude can therefore be precisely adjusted by varying the film thickness. These multilayer luminescence switches hold potential for micro- and nanoscale thermal sensing and imaging applications.

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Dmitriev, Ruslan I., Xavier Intes, and Margarida M. Barroso. "Luminescence lifetime imaging of three-dimensional biological objects." Journal of Cell Science 134, no. 9 (May 1, 2021): 1–17. http://dx.doi.org/10.1242/jcs.254763.

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ABSTRACT A major focus of current biological studies is to fill the knowledge gaps between cell, tissue and organism scales. To this end, a wide array of contemporary optical analytical tools enable multiparameter quantitative imaging of live and fixed cells, three-dimensional (3D) systems, tissues, organs and organisms in the context of their complex spatiotemporal biological and molecular features. In particular, the modalities of luminescence lifetime imaging, comprising fluorescence lifetime imaging (FLI) and phosphorescence lifetime imaging microscopy (PLIM), in synergy with Förster resonance energy transfer (FRET) assays, provide a wealth of information. On the application side, the luminescence lifetime of endogenous molecules inside cells and tissues, overexpressed fluorescent protein fusion biosensor constructs or probes delivered externally provide molecular insights at multiple scales into protein–protein interaction networks, cellular metabolism, dynamics of molecular oxygen and hypoxia, physiologically important ions, and other physical and physiological parameters. Luminescence lifetime imaging offers a unique window into the physiological and structural environment of cells and tissues, enabling a new level of functional and molecular analysis in addition to providing 3D spatially resolved and longitudinal measurements that can range from microscopic to macroscopic scale. We provide an overview of luminescence lifetime imaging and summarize key biological applications from cells and tissues to organisms.

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Ovchinnikov, Oleg V., Mikhail S. Smirnov, Irina G. Grevtseva, Tamara S. Kondratenko, and Aleksey S. Perepelitsa. "Control of the direction of energy transfer in associates of colloidal quantum dots Ag2S/TGA and dye molecules." EPJ Web of Conferences 190 (2018): 04015. http://dx.doi.org/10.1051/epjconf/201819004015.

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The possibilities for changing the direction of energy transfer in hybrid associates of colloidal Ag2S quantum dots (QDs) and thionine molecules are analyzed. The studies were performed by transmission electron microscopy, absorption and luminescence spectroscopy, PL decay study (time correlated single photon counting). An increasing of the average QDs size from 1.8 nm to 5.5 nm, and also a shift of the luminescence band from 630 nm to 950 nm, were found at using of TGA molecules and sodium sulfide as a sulfur precursor. Hybrid association of QDs (1.8 nm) with TH+ molecules leads to quenching of QDs luminescence with a simultaneous reduction of the luminescence lifetime from 13.7 to 6.5 ns. An association of QDs with a luminescence band maximum of 950 nm with TH+ molecules leads to quenching of TH+ luminescence and a reduction in its lifetime of luminescence from 0.43 to 0.3 ns. It was concluded that the reduction of lifetime of luminescence caused by the resonant nonradiative energy transfer between the components of the associates. An increasing in the average size of QDs leads to a change in the direction of energy transfer between the components of the associates.

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Rood, Marcus T. M., Maria Oikonomou, Tessa Buckle, Marcel Raspe, Yasuteru Urano, Kees Jalink, Aldrik H. Velders, and Fijs W. B. van Leeuwen. "An activatable, polarity dependent, dual-luminescent imaging agent with a long luminescence lifetime." Chem. Commun. 50, no. 68 (2014): 9733–36. http://dx.doi.org/10.1039/c4cc04015e.

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A combination of two quenching interactions was incorporated in a new activatable imaging agent. Partial and total activation of luminescence can be achieved, as well as luminescence lifetime imaging.

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Zhang, Wenjun, Xuefeng Zou, and Jinfeng Zhao. "Preparation and performance of a novel graphene oxide sheets modified rare-earth luminescence material." Journal of Materials Chemistry C 3, no. 6 (2015): 1294–300. http://dx.doi.org/10.1039/c4tc02172j.

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Plonska, Malgorzata, Wojciech A. Pisarski, and Joanna Pisarska. "Luminescence Properties of Ytterbium Activated PLZT Ceramics." Advances in Science and Technology 98 (October 2016): 64–69. http://dx.doi.org/10.4028/www.scientific.net/ast.98.64.

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In the present work the influence of co-doping with ytterbium ions (for 0, 0.5, 1.5, 2.5 wt.% of Yb3+) on physical properties of 8/65/35 PLZT was studied. The ceramic powders were synthesized by the modified sol-gel method, and underwent consolidation by the pressure-less sintering techniques, in Ts=1200°C/6h. Our investigations give a detailed account of the relationships between concentrations of trivalent ytterbium ions in PLZT matrix, on their structure, microstructure, as well as luminescence properties. Near-infrared luminescence spectra at about 1020 nm were registered, which correspond to 2F5/2 - 2F7/2 transition of Yb3+. Based on decay measurements, the luminescence lifetimes for the 2F5/2 excited state of Yb3+ were determined. Luminescence decay analysis indicates that the 2F5/2 lifetime increase with increasing activator concentration (Yb3+) in PLZT ceramic matrix.

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Chan, Sing Po, Z. J. Fuller, J. N. Demas, and B. A. DeGraff. "Optimized Gating Scheme for Rapid Lifetime Determinations of Single-Exponential Luminescence Lifetimes." Analytical Chemistry 73, no. 18 (September 2001): 4486–90. http://dx.doi.org/10.1021/ac0102361.

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Ji, Zeliang, Yao Cheng, Xiangshui Cui, Hang Lin, Ju Xu, and Yuansheng Wang. "Heating-induced abnormal increase in Yb3+ excited state lifetime and its potential application in lifetime luminescence nanothermometry." Inorganic Chemistry Frontiers 6, no. 1 (2019): 110–16. http://dx.doi.org/10.1039/c8qi01052h.

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Tang, Ruijun, Jianxun Wang, Yueshan Xu, Shasha Wang, and Gejihu De. "Controlled synthesis and upconversion luminescence properties of heterogeneous isomorphic Yb³⁺/Er³⁺ co-doped Na_0.9Ca_0.9Gd_1.1F₆ nanorods with multiple luminescence centers." CrystEngComm 24, no. 2 (2022): 251–59. http://dx.doi.org/10.1039/d1ce01435h.

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Heterogeneous isomorphic β-Na0.9Ca0.9Gd1.1F6:Yb3+/Er3+ nanorods with multiple luminescence centers were successfully synthesized and exhibited strong luminescence, long decay lifetime and high optical stability.

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Li, Benhao, Jing Lin, Peng Huang, and Xiaoyuan Chen. "Near-infrared probes for luminescence lifetime imaging." Nanotheranostics 6, no. 1 (2022): 91–102. http://dx.doi.org/10.7150/ntno.63124.

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34

Fu-Jun, Zhang, Xu Zheng, Zhao Su-Ling, Lou Zhi-Dong, Yang Sheng-Yi, and Xu Xu-Rong. "Estimation of luminescence lifetime in frequency domain." Chinese Physics 15, no. 3 (March 2006): 526–30. http://dx.doi.org/10.1088/1009-1963/15/3/013.

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35

van der Voort, D. D., N. J. Dam, A. M. Sweep, R. P. J. Kunnen, G. J. F. van Heijst, H. J. H. Clercx, and W. van de Water. "Decreasing luminescence lifetime of evaporating phosphorescent droplets." Applied Physics Letters 109, no. 23 (December 5, 2016): 234103. http://dx.doi.org/10.1063/1.4971987.

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36

Harukawa, N., S. Murakami, S. Tamon, S. Ijuin, A. Ohmori, K. Abe, and T. Shigenari. "Temperature dependence of luminescence lifetime in Cu2O." Journal of Luminescence 87-89 (May 2000): 1231–33. http://dx.doi.org/10.1016/s0022-2313(99)00524-4.

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Morgan, C. G., A. C. Mitchell, J. G. Murray, and E. J. Wall. "New approaches to lifetime-resolved luminescence imaging." Journal of Fluorescence 7, no. 1 (March 1997): 65–73. http://dx.doi.org/10.1007/bf02764579.

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38

Holst, Gerhard, and Björn Grunwald. "Luminescence lifetime imaging with transparent oxygen optodes." Sensors and Actuators B: Chemical 74, no. 1-3 (April 2001): 78–90. http://dx.doi.org/10.1016/s0925-4005(00)00715-2.

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Tan, Meiling, Blanca del Rosal, Yuqi Zhang, Emma Martín Rodríguez, Jie Hu, Zhigang Zhou, Rongwei Fan, et al. "Rare-earth-doped fluoride nanoparticles with engineered long luminescence lifetime for time-gated in vivo optical imaging in the second biological window." Nanoscale 10, no. 37 (2018): 17771–80. http://dx.doi.org/10.1039/c8nr02382d.

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40

Miyazawa, Tetsuya, Takeshi Tawara, and Hidekazu Tsuchida. "Carrier Lifetime Control of 4H-SiC Epitaxial Layers by Boron Doping." Materials Science Forum 897 (May 2017): 51–54. http://dx.doi.org/10.4028/www.scientific.net/msf.897.51.

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An epitaxial growth technique for 4H-SiC with B doping was developed to control the carrier lifetimes of the epilayers. A linear relationship was observed between the B doping concentration and the flow rate of tri-ethyl-boron, which was used as the B doping source. A room temperature photoluminescence spectrum of a N-and B-doped epilayer showed a broad B-related peak at 2.37 eV instead of a band-edge luminescence, which indicates that the carrier recombination path was changed by the B doping. The minority carrier lifetime decreased (< 30 ns at 250°C) with increasing B doping concentration. The thermal stability of the short carrier lifetime was compared with a conventional carrier lifetime reduction method, namely an electron irradiation technique. After thermal annealing at 1700°C, the carrier lifetime of the electron irradiated epilayer recovered while that of the B-doped epilayer remained, indicating that the carrier lifetime controlled by the B doping technique was more stable against the thermal processes.

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41

Smola, Serhii, Nataliia Rusakova, Olga Snurnikova, Elena Alekseeva, and Tatyana Kirichenko. "PECULIARITIES OF STRUCTURE AND SPECTRAL-LUMINESCENT PROPERTIES OF CARBOXYMETHOXY-SUBSTITUTED CALIX[4]ARENES AND THEIR COMPLEXES WITH LANTHANIDES." Ukrainian Chemistry Journal 86, no. 3 (April 7, 2020): 9–18. http://dx.doi.org/10.33609/0041-6045.86.3.2020.9-18.

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Spectral-luminescent properties of a variety of carboxymethoxy-substituted p-tert-butyl-calix[4]arenes and their complexes with lanthanides (Nd, Er, Yb) that exhibit the 4f-luminescence in the IR-spectrum region have been investigated. The effect of substitution of hydrogen phenolic atoms by carboxymethoxy groups on the stability and spectral-luminescent characteristics of both the ligands and lanthanide complexes was analyzed. Thus, based on the combination of the results obtained by means of elemental analysis, mass spectrometry, IR and 1H NMR spectroscopy, and taking into account the data of pH-metric titration, spectrophotometric and luminescence measurements, it can be concluded that lanthanide ions form neutral complexes of 1:1 ratio with L1H4 - L4H4. This is explained by the presence of mobile hydrogen atoms of phenol and/or carboxyl groups in the molecules of these ligands. An increase in the number of donor substituents leads to changes in the number of solvent molecules in the series L3H4 < L1H4 < L2H4 < L4H4 from 0.8 to 2.4 for neodymium complexes, from 1.2 to 2.2 - for ytterbium complexes. Both the quantum yield and lifetime of the 4f-luminescence of the neodymium and ytterbium complexes and also the luminescence intensity of the erbium-containing compounds change in the same order.

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Wang, Chen, Luyao Feng, Junxiao Liu, Jing Fu, Jinglin Shen, and Wei Qi. "Manipulating the Assembly of Au Nanoclusters for Luminescence Enhancement and Circularly Polarized Luminescence." Nanomaterials 12, no. 9 (April 25, 2022): 1453. http://dx.doi.org/10.3390/nano12091453.

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Au nanocluster (AuNCs)-based luminescent functional materials have attracted the interest of researchers owing to their small size, tractable surface modification, phosphorescence lifetime and biocompatibility. However, the poor luminescence quantum yield (QY) of AuNCs limits their practical applications. Herein, we synthesized a type of AuNCs modified by 4,6-diamino-2-mercaptopyrimidine hydrate (DPT-AuNCs). Furthermore, organic acids, i.e., citric acid (CA) and tartaric acid (TA), were chosen for co-assembly with DPT-AuNCs to produce AuNCs-based luminescent materials with enhanced emission. Firstly, it was found that CA could significantly enhance the emission of DPT−AuNCs with the formation of red emission nanofibers (QY = 17.31%), which showed a potential for usage in I− detection. The n···π/π···π interaction between the CA and the DPT ligand was proposed as crucial for the emission. Moreover, chiral TA could not only improve the emission of DPT-AuNCs, but could also transfer its chirality to DPT-AuNCs and induce the formation of circularly polarized luminescence (CPL)-active nanofibers. It was demonstrated that the CPL signal could increase 4.6-fold in a ternary CA/TA/DPT-AuNCs co-assembly system. This work provides a convenient way to build AuNCs-based luminescent materials as probes, and opens a new avenue for building CPL-active materials by achiral NCs through a co-assembly strategy.

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43

Wang, Chen, Luyao Feng, Junxiao Liu, Jing Fu, Jinglin Shen, and Wei Qi. "Manipulating the Assembly of Au Nanoclusters for Luminescence Enhancement and Circularly Polarized Luminescence." Nanomaterials 12, no. 9 (April 25, 2022): 1453. http://dx.doi.org/10.3390/nano12091453.

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Au nanocluster (AuNCs)-based luminescent functional materials have attracted the interest of researchers owing to their small size, tractable surface modification, phosphorescence lifetime and biocompatibility. However, the poor luminescence quantum yield (QY) of AuNCs limits their practical applications. Herein, we synthesized a type of AuNCs modified by 4,6-diamino-2-mercaptopyrimidine hydrate (DPT-AuNCs). Furthermore, organic acids, i.e., citric acid (CA) and tartaric acid (TA), were chosen for co-assembly with DPT-AuNCs to produce AuNCs-based luminescent materials with enhanced emission. Firstly, it was found that CA could significantly enhance the emission of DPT−AuNCs with the formation of red emission nanofibers (QY = 17.31%), which showed a potential for usage in I− detection. The n···π/π···π interaction between the CA and the DPT ligand was proposed as crucial for the emission. Moreover, chiral TA could not only improve the emission of DPT-AuNCs, but could also transfer its chirality to DPT-AuNCs and induce the formation of circularly polarized luminescence (CPL)-active nanofibers. It was demonstrated that the CPL signal could increase 4.6-fold in a ternary CA/TA/DPT-AuNCs co-assembly system. This work provides a convenient way to build AuNCs-based luminescent materials as probes, and opens a new avenue for building CPL-active materials by achiral NCs through a co-assembly strategy.

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44

Hömmerich, U., J. T. Seo, J. D. MacKenzie, C. R. Abernathy, R. Birkhahn, A. J. Steckl, and J. M. Zavada. "Comparison of the Optical Properties of Er3+ Doped Gallium Nitride Prepared by Metalorganic Molecular Beam Epitaxy (Mombe) and Solid Source Molecular Beam Epitaxy (SSMBE)." MRS Internet Journal of Nitride Semiconductor Research 5, S1 (2000): 824–30. http://dx.doi.org/10.1557/s1092578300005135.

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We report on the luminescence properties of Er doped GaN grown prepared by metalorganic molecular beam epitaxy (MOMBE) and solid-source molecular beam epitaxy (SSMBE) on Si substrates. Both types of samples emitted characteristic 1.54 µm PL resulting from the intra-4f Er3+ transition 4I13/2→4I15/2. Under below-gap excitation the samples exhibited very similar 1.54 µm PL intensities. On the contrary, under above-gap excitation GaN: Er (SSMBE) showed ∼80 times more intense 1.54 µm PL than GaN: Er (MOMBE). In addition, GaN: Er (SSMBE) also emitted intense green luminescence at 537 nm and 558 nm, which was not observed from GaN: Er (MOMBE). The average lifetime of the green PL was determined to be 10.8 µs at 15 K and 5.5 µs at room temperature. A preliminary lifetime analysis suggests that the decrease in lifetime is mainly due to the strong thermalization between the 2H11/2 and 4S3/2 excited states. Nonradiative decay processes are expected to only weakly affect the green luminescence.

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45

Chauvin, Anne-Sophie, Frédéric Thomas, Bo Song, Caroline D. B. Vandevyver, and Jean-Claude G. Bünzli. "Synthesis and cell localization of self-assembled dinuclear lanthanide bioprobes." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 371, no. 1995 (July 28, 2013): 20120295. http://dx.doi.org/10.1098/rsta.2012.0295.

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Lanthanide bioprobes and bioconjugates are ideal luminescent stains in view of their low propensity to photobleaching, sharp emission lines and long excited state lifetimes permitting time-resolved detection for enhanced sensitivity. In this paper, we expand our previous work which demonstrated that self-assembled dinuclear triple-stranded helicates [Ln 2 (L C2X ) 3 ] behave as excellent cell and tissue labels in immunocytochemical and immunohistochemical assays. The synthetic strategy of the hexadentate ditopic ligands incorporating dipicolinic acid, benzimidazole units and polyoxyethylene pendants is revisited in order to provide a more straightforward route and to give access to further functionalization of the polyoxyethylene arms by incorporating a terminal function X. Formation of the helicates [Ln 2 (L C2X ) 3 ] ( X =COOH, CH 2 OH, COEt, NH 2 , phthalimide) is ascertained by several experimental techniques and their stability tested against diethylenetriaminepentaacetate. Their photophysical properties (quantum yield, lifetime, radiative lifetime and sensitization efficiency) are presented and compared with those of the parent helicates [Ln 2 (L C2 ) 3 ]. Finally, the cellular uptake of five Eu III helicates is monitored by time-resolved luminescence microscopy and their localization in HeLa cells established by co-staining experiments.

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46

Gao, Cunjin, Pengrui Zheng, Quanxiao Liu, Shuang Han, Dongli Li, Shiyong Luo, Hunter Temple, et al. "Recent Advances of Upconversion Nanomaterials in the Biological Field." Nanomaterials 11, no. 10 (September 22, 2021): 2474. http://dx.doi.org/10.3390/nano11102474.

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Rare Earth Upconversion nanoparticles (UCNPs) are a type of material that emits high-energy photons by absorbing two or more low-energy photons caused by the anti-stokes process. It can emit ultraviolet (UV) visible light or near-infrared (NIR) luminescence upon NIR light excitation. Due to its excellent physical and chemical properties, including exceptional optical stability, narrow emission band, enormous Anti-Stokes spectral shift, high light penetration in biological tissues, long luminescent lifetime, and a high signal-to-noise ratio, it shows a prodigious application potential for bio-imaging and photodynamic therapy. This paper will briefly introduce the physical mechanism of upconversion luminescence (UCL) and focus on their research progress and achievements in bio-imaging, bio-detection, and photodynamic therapy.

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Mykhaylyk, V. B., A. Wagner, and H. Kraus. "Non-contact luminescence lifetime cryothermometry for macromolecular crystallography." Journal of Synchrotron Radiation 24, no. 3 (April 4, 2017): 636–45. http://dx.doi.org/10.1107/s1600577517003484.

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Temperature is a very important parameter when aiming to minimize radiation damage to biological samples during experiments that utilize intense ionizing radiation. A novel technique for remote, non-contact,in situmonitoring of the protein crystal temperature has been developed for the new I23 beamline at the Diamond Light Source, a facility dedicated to macromolecular crystallography (MX) with long-wavelength X-rays. The temperature is derived from the temperature-dependent decay time constant of luminescence from a minuscule scintillation sensor (<0.05 mm3) located in very close proximity to the sample under test. In this work the underlying principle of cryogenic luminescence lifetime thermometry is presented, the features of the detection method and the choice of temperature sensor are discussed, and it is demonstrated how the temperature monitoring system was integrated within the viewing system of the endstation used for the visualization of protein crystals. The thermometry system was characterized using a Bi4Ge3O12crystal scintillator that exhibits good responsivity of the decay time constant as a function of temperature over a wide range (8–270 K). The scintillation sensor was calibrated and the uncertainty of the temperature measurements over the primary operation temperature range of the beamline (30–150 K) was assessed to be ±1.6 K. It has been shown that the temperature of the sample holder, measured using the luminescence sensor, agrees well with the expected value. The technique was applied to characterize the thermal performance of different sample mounts that have been used in MX experiments at the I23 beamline. The thickness of the mount is shown to have the greatest impact upon the temperature distribution across the sample mount. Altogether, these tests and findings demonstrate the usefulness of the thermometry system in highlighting the challenges that remain to be addressed for the in-vacuum MX experiment to become a reliable and indispensable tool for structural biology.

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Plant, Randall L., and David H. Burns. "Quantitative, Depth-Resolved Imaging of Oxygen Concentration by Phosphorescence Lifetime Measurement." Applied Spectroscopy 47, no. 10 (October 1993): 1594–99. http://dx.doi.org/10.1366/0003702934334868.

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Minimally invasive determination of oxygen concentration can be made by measuring phosphorescence lifetime. We describe a technique for depth-resolved measurements of oxygen concentration using confocal imaging of phosphorescence lifetime. A confocal imaging system is used to obtain depth-resolved measurements of phosphorescence decay. The spatial resolution of the system is characterized in terms of the Line Spread Function and shown to be similar in both lateral and depth directions. Lifetimes are calculated with the use of the Rapid Lifetime Determination technique. One- and two-dimensional quantitative images of oxygen concentration in a test specimen are rapidly generated from luminescence decay data. Measurements are made for oxygen concentrations ranging from 2 to 90 µM. A linear relationship between Pdmeso-tetra-(4-sulfonato-phenyl)-porphine phosphorescence inverse lifetime and oxygen concentration is determined. The presence of an intervening solution of different oxygen concentration does not significantly affect the concentration measurements made with the use of depth-resolved imaging techniques.

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Ru, Jing, Yixuan Shi, Qiang Guo, Boxuan Hu, Leilei Li, Yanlan Wang, and Chunlin Ma. "Two Cd(II)-Based MOFs Constructed from Tris(30-F-40-carboxybiphenyl)amine: Synthesis, Crystal Structure, Luminescence Sensing towards Nitrophenols and Acetylacetone." Crystals 12, no. 12 (November 24, 2022): 1708. http://dx.doi.org/10.3390/cryst12121708.

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Two new luminescent metal-organic frameworks (MOFs), namely [Cd4(TFBA)3(H2O)4]n (CdMOF-1) and [Cd(TFBA) (bipy)]n (CdMOF-2) (H3TFBA = tris(3′-F-4′-carboxybiphenyl)amine, 4,4′-bipy = 4,4’-bipyridine), have been prepared and successfully constructed via solvothermal conditions. Single-crystal structure analysis reveals that CdMOF-1 are two-dimensional network containing [Cd4O26] units. CdMOF-2 shows a non-interpenetration 3D microporous structure with a hexagon pore of 24.6 × 25.9 Å. Notably, CdMOF-2 exhibits turn off fluorescence behavior towards picric acid (TNP) and 4-Nitrophenol (PNP) with a limit of detection (LOD) value of 9.2 × 10−6 M and 1.81 × 10−5 M, respectively. Furthermore, CdMOF-2 shows obvious turn-on luminescence responses toward acetylacetone (Acac) with luminescence red-shift and a detection limit of 19.40 ppm. Additionally, the possible quenching or enhancing mechanism during the sensing process were evaluated by PXRD, UV-vis, and luminescence decay lifetime.

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Marciniak, L., and K. Trejgis. "Luminescence lifetime thermometry with Mn3+–Mn4+ co-doped nanocrystals." Journal of Materials Chemistry C 6, no. 26 (2018): 7092–100. http://dx.doi.org/10.1039/c8tc01981a.

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Journal articles on the topic 'Luminescence lifetime'

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