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We report the electrochemiluminescence (ECL) of a 3d6 Cr(0) complex ([Cr(LMes)3]; λem=735 nm) with comparable photophysical properties to those of ECL‐active complexes of 4d6 or 5d6 precious metal ions. The electrochemical potentials of [Cr(LMes)3] are more negative than those of [Ir(ppy)3] and render the [Cr(LMes)3]* excited state inaccessible through conventional co‐reactant ECL with tri‐n‐propylamine or oxalate. ECL can be obtained, however, through the annihilation route in which potentials sufficient to oxidise and reduce the luminophore are alternately applied. When combined with [Ir(ppy)3] (λem=520 nm), the annihilation ECL of [Cr(LMes)3] was greatly enhanced whereas that of [Ir(ppy)3] was diminished. Under appropriate conditions, the relative intensities of the two spectrally distinct emissions can be controlled through the applied potentials. From this starting point for ECL with 3d6 metal complexes, we discuss some directions for future development. [ABSTRACT FROM AUTHOR]

We report the electrochemiluminescence (ECL) of a 3d6 Cr(0) complex ([Cr(LMes)3]; λem=735 nm) with comparable photophysical properties to those of ECL‐active complexes of 4d6 or 5d6 precious metal ions. The electrochemical potentials of [Cr(LMes)3] are more negative than those of [Ir(ppy)3] and render the [Cr(LMes)3]* excited state inaccessible through conventional co‐reactant ECL with tri‐n‐propylamine or oxalate. ECL can be obtained, however, through the annihilation route in which potentials sufficient to oxidise and reduce the luminophore are alternately applied. When combined with [Ir(ppy)3] (λem=520 nm), the annihilation ECL of [Cr(LMes)3] was greatly enhanced whereas that of [Ir(ppy)3] was diminished. Under appropriate conditions, the relative intensities of the two spectrally distinct emissions can be controlled through the applied potentials. From this starting point for ECL with 3d6 metal complexes, we discuss some directions for future development. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) represent a new type of crystalline porous polymers that possess pre‐designed skeletons, uniform nanopores, and ordered π structure. These attributes make them well‐suited for the design of light‐emitting materials. However, the majority of COFs exhibits poor luminescence due to aggregation‐caused quenching (ACQ), resulting from the strong interaction between adjacent layers. To break the limitation, the building units with three methoxy groups on the walls are used to construct TM‐OMe‐EBTHz‐COF, which suppresses the ACQ effects to improve light‐emitting activity of COF. The TM‐OMe‐EBTHz‐COF exhibits a notable emission of yellow‐green luminescence in the solid state, with a remarkably high absolute quantum yield of 21.1%. The methoxy groups and hydrazine linkage form three coordination sites, contributing to excellent performance in metal ions sensing. The TM‐OMe‐EBTHz‐COF demonstrates high sensitivity and selectivity to Fe3+ ion. Importantly, the low detection limit is below 150 nanomolar, ranking it among the best‐performing Fe3+ sensor systems. [ABSTRACT FROM AUTHOR]

Hydrogen‐bonded organic frameworks (HOFs) represent an emerging class of porous crystalline materials, have attracted growing interest in the field of fluorescence sensing area due to their distinctive luminescent characteristics, large surface area and abundant recognition sites. Herein, the porous material HOF‐BTB‐NH2 featuring one‐dimensional pore structure was successfully synthesized through hydrogen‐bonding self‐assembly using the organic building molecule 2,4,6‐Tris(4‐carboxyphenyl)aniline (BTB‐NH2) in methanol. HOF‐BTB‐NH2 showed excellent sensitivity and selectivity for metal ion Cu2+ and anion CO32−, and the limits of detection (LOD) reached 0.23 μM and 0.33 μM, respectively. In addition, HOF‐BTB‐NH2 was employed as a biosensing material for the highly selective and sensitive detection of dopamine (DA). The synthesis of porous HOF‐BTB‐NH2 and the excellent sensing performance greatly expanded the application of hydrogen‐bonded organic framework materials in fluorescence sensing. [ABSTRACT FROM AUTHOR]

The chalcone compound DHPO was synthesized through a chemical reaction between 1-(2-hydroxyphenyl)-ethanone and 3,4-dimethoxy benzaldehyde under ultrasound irradiation. The interaction between the DHPO compound and several metal ions was studied using fluorescence behavior, revealing that the chalcone function as a "turn on and turn off" switch fluorescent sensor, for selectively and sensitively detecting Fe3+ ions. The process of fluorescence quenching and complexation of DHPO with Fe3+ ion was further studied using methods such as Benesi-Hildebrand, Stern-Volmer plot, and job plot. [ABSTRACT FROM AUTHOR]

Slightly different reaction conditions afforded two distinct cavity‐shaped cis‐chelating diphosphanes from the same starting materials, namely diphenyl(2‐phosphanylphenyl)phosphane and an α–cyclodextrin‐derived dimesylate. Thanks to their metal‐confining properties, the two diphosphanes form only mononuclear [CuX(PP)] complexes (X=Cl, Br, or I) with the tricoordinated metal ion located just above the center of the cavity. The two series of CuI complexes display markedly different luminescence properties that are both influenced by the electronic properties of the ligand and the unique steric environment provided by the cyclodextrin (CD) cavity. The excited state lifetimes of all complexes are significantly longer than those of the cavity‐free analogues suggesting peculiar electronic effects that affect radiative deactivation constants. The overall picture stemming from absorption and emission data suggests close‐lying charge‐transfer (MLCT, XLCT) and triplet ligand‐centered (LC) excited states. [ABSTRACT FROM AUTHOR]

Mn4+‐activated CaAl12O19 (CAO: Mn4+) is recognized as a promising candidate for red phosphor used in wide color gamut displays. However, the spontaneous self‐reduction of Mn4+ to Mn2+ occurs for charge compensation through Mn2+‐Mn4+ substitution for Al3+‐Al3+, lowering the quantum efficiency of Mn4+. To suppress the self‐reduction, some divalent metal ions, including Ba2+, Sr2+, Cd2+, Zn2+, and Mg2+, are added for charge compensation instead of Mn2+, but only small luminescence enhancement is observed. In this paper, remarkable luminescence enhancement in CAO: Mn4+ via co‐doping Be2+ is reported. The photoluminescence properties are studied as a function of Be2+ doping concentration, and the optimal Be2+ concentration of 0.01 is found. The internal quantum efficiency of 74.9% and external quantum efficiency of 56.3% are achieved under UV excitation, higher than those via co‐doping other divalent metal ions. This study indicates that the addition of Be2+ dominates the charge compensation because Be2+ is closer to Al3+ in size than Mn2+ and other divalent metal ions. The backlight light‐emitting diodes using CAO: Mn4+, Be2+ are fabricated, exhibiting a 110.1% Nation Television Standards Committee (NTSC) color gamut, wider than both the current commercial backlight using K2SiF6: Mn4+ (KSF) red phosphor and the conventional one using YAG yellow phosphor. [ABSTRACT FROM AUTHOR]

A novel time-resolved fluorescence nanoprobe (PBMO, PLNR-BSA-Mn2+-OPD) is fabricated for the label-free determination of acetylcholinesterase (AChE). The ZnGeO:Mn persistent luminescence nanorod (PLNR) and Mn(II) are, respectively, exploited as the signal molecule and quencher to construct the PBMO nanopobe using bovine serum albumin (BSA) as the surface-modified shell and o-phenylenediamine (OPD) as the reducing agent. In the presence of H2O2, the persistent luminescence of PBMO at 530 nm is enhanced remarkably within 30 s due to the oxidation of Mn(II). H2O2 can react with thiocholine (TCh), which is produced through the enzymatic degradation of acetylcholine (ATCh) by AChE. The PBMO nanoprobe is successfully applied to the determination of AChE in the linear range of 0.08–10 U L−1, with a detection limit of 0.03 U L−1 (3σ/s). The practicability of this PBMO nanoprobe is confirmed by accurately monitoring AChE contents in human serum samples, giving rise to satisfactory spiking recoveries of 96.2–103.6%. [ABSTRACT FROM AUTHOR]

In this study, the impact of two co-extracting and interfering metal ions in the coordination process of Ln(III) ions using the luminescence spectroscopic technique by taking Eu(III) as the probe was explored for the first time. The solvent extraction route was adopted for the ligation process, and the organic phase composition was a mixture of diglycolamide (DGA) ligand N,N,N′,N′- tetra(ethylhexyl)diglycolamide (T2EHDGA) and tri-n-butyl phosphate (TBP) in n-dodecane (n-DD) medium. Zr(IV) and Pd(II) were considered as co-extracting metal ions along with Eu(III) extraction from nitric acid medium. The varied concentrations of Zr(IV) and Pd(II) in the feed phase led to significant changes in Eu(III) distribution (or luminescence). The extraction factors of Eu(III) decreased in the presence of Zr(IV) while the presence of Pd(II) followed an opposite trend. The presence of TBP in the T2EHDGA/n-DD phase increases the acid (or Eu(III)) concentration in the extracted phase. The emission patterns of Eu(III) in the presence of Zr(IV) and Pd(II) were contradictory to each other, i.e., Zr(IV) enhanced the peak intensity of 5D0 → 7F2 transition, whereas Pd(II) offered a decreased value. The asymmetry ratio (AR) and the lifetime (τ) data of Eu(III) emission both in the aqueous and organic phases with or without Zr(IV) (or Pd(II)) were appraised to comprehend the nature of the Eu(III) complex. [ABSTRACT FROM AUTHOR]

Metal–organic supramolecular polymers (MOSPs) with multicolor circularly polarized luminescence (CPL) and handedness inversion were constructed from the coordination-driven assembly of pyridine–cyanostilbene–cholesterol and metal salts by modulating the treatment modes, solvents, and metal ions. [ABSTRACT FROM AUTHOR]

Alkylation of one of the inner‐core nitrogen atoms is one possible approach to obtain dianionic corrole ligands, suitable for the coordination of divalent metal ions, such as PdII. Inner‐core N‐methylation can be obtained by treating the corrole with CH3I, but the reaction conditions should be optimized to limit the formation of the dimethylated derivative. Two regioisomers, the N‐21 and the N‐22 methyl derivatives are obtained from the reaction, with the first product achieved in a higher amount. Structural characterization of the reaction products evidenced the distortion induced by the introduction of the methyl groups; the N‐methylcorroles are chiral compounds, and the enantiomers were separated by chromatography, with their absolute configuration assigned by ECD computation. Palladium insertion was achieved in the case of monosubstituted corroles, but not with the dimethylated macrocycle; X‐ray characterization of the complexes showed the distortion of the macrocycles. The Pd complexes do not show luminescence emission, but are able to produce singlet oxygen upon irradiation. The PdII complexes were also inserted in human serum albumin (HSA) and dispersed in water; in this case, the protein protects the corroles from photobleaching, and a switch from the type II to the type I mechanism in reactive oxygen species (ROS) production is observed. [ABSTRACT FROM AUTHOR]

Red-emitting Mn4+-doped fluoride phosphors are promising fluorescent material for use in high-performance warm white light emitting diodes (WLEDs). However, low stability and non-green synthesis method limit the development and commercialization of such phosphor. Herein, a series of novel (Li/Na/Cs) 0.4 Ba 0.8 SiF 6 :Mn4+ phosphors with optimized fluorescence properties induced by alkaline metal ions replacement are successfully synthesized via a green and eco-friendly approach. Under the irradiation of 460 nm blue light, Cs 0.4 Ba 0.8 SiF 6 :Mn4+ red phosphor with narrow band emission peak has the best optical performance. The optimal doping concentration of Mn4+ in Cs 0.4 Ba 0.8 SiF 6 host and the reason for concentration quenching are systematically analyzed. Furthermore, the moisture resistance and thermal stability of this phosphor are discussed. After being soaked in deionized water for 90 min, the PL intensity of Cs 0.4 Ba 0.8 SiF 6 :Mn4+ phosphor can maintain at 40% of that in air, which is 4 times higher than commercial K 2 SiF 6 :Mn4+. At the operating temperature of LED (423 K), Cs 0.4 Ba 0.8 SiF 6 :Mn4+ red phosphor can exhibit stable light output intensity and color. A warm WLED with low correlated color temperature of 4336 K, high color rendering index of 88.4 and high lumen efficiency of 105.96 lm/W is fabricated via using Cs 0.4 Ba 0.8 SiF 6 :Mn4+ phosphor as a component of red-light, and the warm WLED can maintain stable output even at high driving currents. Overall, the alkali metal ion replacement and green synthesis strategies have opened up a new perspective for the synthesis of efficient Mn4+-doped fluoride phosphors, which has dual benefits for optimizing the performance of WLED and environmental protection. Novel Cs 0.4 Ba 0.8 SiF 6 :Mn4+ phosphor with efficient water and thermal stability is synthesized by combining alkali metal ion substitution method with green synthesis route for high-performance warm WLED. [Display omitted] • An eco-friendly approach is adopted to synthetic Mn4+-activated fluoride phosphors. • Alkali metal ion replacement enhances the optical properties of Mn4+-doped phosphor. • Cs 0.4 Ba 0.8 SiF 6 :Mn4+ phosphor with excellent stability is obtained. • Warm WLED can be realized using Cs 0.4 Ba 0.8 SiF 6 :Mn4+ as the red light component. [ABSTRACT FROM AUTHOR]

We designed four ternary lanthanide tris-(β-diketonate) complexes of the form [Ln(tta)3(tpy-HImzphen)], where Ln = LaIII, EuIII, SmIII and TbIII; tta = (2-theonyltrifluoroacetonate) and tpy-HImzphen = 2-(4-[2,2′:6′,2′′]terpyridin-4′-yl-phenyl)-1H-phenanthro[9,10-d]imidazole. All the complexes have been thoroughly characterized by standard analytical tools and spectroscopic techniques including single crystal X-ray diffraction. In situ generation of the complexes was also monitored via absorption and emission spectroscopy upon incremental addition of the respective lanthanide precursor {Ln(tta)3(H2O)2} to the dichloromethane solution of the terpyridyl-imidazole ligand. The photophysical behaviors of all the complexes were thoroughly investigated via absorption and both steady-state and time-resolved emission spectroscopic techniques. The emission spectral measurements were carried out at both room temperature and 77 K to understand the deactivation dynamics of the excited states and elucidate the distinctive luminescence responses from the four lanthanide metal ions owing to the introduction of the terpyridyl-based ancillary ligand. [ABSTRACT FROM AUTHOR]

I-III-VI type QDs have unique optoelectronic properties such as low toxicity, tunable bandgaps, large Stokes shifts and a long photoluminescence lifetime, and their emission range can be continuously tuned in the visible to near-infrared light region by changing their chemical composition. Moreover, they can avoid the use of heavy metal elements such as Cd, Hg and Pb and highly toxic anions, i.e., Se, Te, P and As. These advantages make them promising candidates to replace traditional binary QDs in applications such as light-emitting diodes, solar cells, photodetectors, bioimaging fields, etc. Compared with binary QDs, multiple QDs contain many different types of metal ions. Therefore, the problem of different reaction rates between the metal ions arises, causing more defects inside the crystal and poor fluorescence properties of QDs, which can be effectively improved by doping metal ions (Zn2+, Mn2+ and Cu+) or surface coating. In this review, the luminous mechanism of I-III-VI type QDs based on their structure and composition is introduced. Meanwhile, we focus on the various synthesis methods and improvement strategies like metal ion doping and surface coating from recent years. The primary applications in the field of optoelectronics are also summarized. Finally, a perspective on the challenges and future perspectives of I-III-VI type QDs is proposed as well. [ABSTRACT FROM AUTHOR]

The synthesis of a novel bis‐stannylene pincer ligand and its complexation with coinage metals (CuI, AgI and AuI) are described. All coinage metal centres are in tetrahedral coordination environments in the solid state and are exclusively coordinated by four neutral SnII donors. 119Sn NMR provided information about the behaviour in solution. All of the isolated compounds have photoluminescent properties, and these were investigated at low and elevated temperatures. Compared to the free bis‐stannylene ligand, coordination to coinage metals led to an increase in the luminescence intensity. The new compounds were investigated in detail through all‐electron relativistic density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

Complexes emitting in the blue spectral region are attractive materials for developing white-colored light sources. Here, we report the luminescence properties of novel coordination compounds based on the trivalent group 3, 13 metals, and the 1-phenyl-3-methyl-4-cyclohexylcarbonyl-pyrazol-5-onate (QCH) ligand. [M(QCH)3] (M = Al, Ga, and In), [M(QCH)3(H2O)] (M = Sc, Gd, and Lu), [Lu(QCH)3(DMSO)], and [La(QCH)3(H2O)(EtOH)] complexes were synthesized and structurally characterized by a single-crystal X-ray diffraction study. It has been found that the luminescence quantum yields of the ligand increase by one order of magnitude upon metal coordination. A significant correspondence between the energies of the ligand's excited states and the luminescence quantum yields to the metal ion's atomic numbers was found using molecular spectroscopy techniques. The replacement of the central ion with the heavier one leads to a monotonic increase in singlet state energy, while the energy of the triplet state is similar for all the complexes. Time-resolved measurements allowed us to estimate the intersystem crossing (ISC) rate constants. It was shown that replacing the Al3+ ion with the heavier diamagnetic Ga3+ and In3+ ions decreased the ISC rate, while the replacement with the paramagnetic Gd3+ ion increased the ISC rate, which resulted in a remarkably bright and room-temperature phosphorescence of [Gd(QCH)3(H2O)]. [ABSTRACT FROM AUTHOR]

A new method is presented for the one-step synthesis and real-time monitoring of iridium(III) complex-functionalized AuNPs from the precursor gold(III) chloride (AuCl3). The functionalized AuNPs with an average size of 8 − 20 nm were obtained by the reduction of Au3+ ions by the alkyne group of iridium(III) complexes, which was accompanied by the anchoring iridium(III) complexes on the surface of the nanoparticles. Meanwhile, the luminescence of the iridium(III) complexes was effectively quenched due to distance-dependent fluorescence quenching by AuNPs, thereby enabling luminescence monitoring of the formation process of the functionalized AuNPs and obtaining scattering information and spectral information in real time. Moreover, this method was applied to the determination of Au3+ ions in buffer with a limit of detection of 0.38 μM at 700 nm in luminescence mode, while the detection limit for absorbance was 10.04 μM. Importantly, the multimodal detection strategy alleviates interference from other metal ions. Furthermore, the iridium(III) alkyne complexes were capable of imaging mitochondrial Au3+ ions in living cells. Taken together, this work opens a new avenue for convenient synthesis and monitoring formation of functionalized AuNPs, and also provides a tool for selective determination of Au3+ ions in solution and in cellulo. [ABSTRACT FROM AUTHOR]

Near-infrared long afterglow materials have the characteristics of non-obscuring bio autofluorescence and good photo/chemical stability. They can play an essential role in bioimaging, whereas LiGa5O8:Cr3+ has long afterglow and optical photoexcitation properties. In this paper, LiGa5O8:Cr3+ nanophosphors were successfully synthesized by hydrothermal method. X-ray diffraction (XRD) patterns were recorded using an X-ray diffractometer. Luminescence spectra and decay curves were obtained via a fluorescence spectrophotometer. The microstructural properties of the samples were analyzed using scanning electron microscopy (SEM). Transmission electron microscopy (TEM) images were recorded on a TEM instrument. Thermoluminescence spectrometer was employed to obtain a thermoluminescence curve. Using Tween 20 as the experimental chelating agent, it was found that the ratio of total metal ions to Tween 20 significantly affected the luminescence properties of LiGa5O8:Cr3+. When the ratio of total metal ions to Tween 20 was 7 : 1, the sample had less impurity phase, high crystallinity, regular grain shape, and a size of about 100 nm. The fluorescence spectra showed that the main excitation peaks were 410 nm and 608 nm, and the main emission peaks were 720 nm. The sample with a ratio of 7 : 1 had a higher relative intensity than all other samples, with more effective traps and greater stored energy to produce more luminescent carriers. The kinetic order at this point was 2. It provides a solid basis for bioimaging. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots (QDs) have attracted much attention owing to their specific structures. Doping of metal ions has been extensively investigated to endow QDs with novel optical, electronic, magnetic properties. Herein, we demonstrate an effective strategy to realized excellent dual mode luminescence thermometry based on manganese(II) doped CsPbCl 3 QDs. Photoluminescence quantum yield (PLQY) is improved almost 10 times from 4.8% for undoped CsPbCl 3 to 47.3% for CsPbCl 3 :0.1Mn2+ QDs. The long-term stability is achieved by substitution of Pb2+ by smaller Mn2+ ions, without additional distributing the QDs into glasses or metal-oxide-frameworks (MOFs). Taking advantage of this effective doping strategy, the Mn2+-doped CsPbCl 3 QDs are employed to act as excellent dual-mode luminescent probes towards temperature sensing. The maximum relative sensitivity (SR) reaches as high as 7.38% K-1 and 2.13% K-1 via fluorescence intensity ratio (FIR) and full width at half maximum (FWHM) methods, respectively. The repeatability of luminescence thermometry is distinguished for Mn2+ doped CsPbCl 3 QDs as well. It opens an effective strategy to develop nano optical temperature sensing based on perovskite quantum dots. [ABSTRACT FROM AUTHOR]

This review summarizes the data on the synthesis of coordination compounds containing two or more different metal ions based on fluorinated β-diketonates. Heterometallic systems are of high interest in terms of their potential use in catalysis, medicine and diagnostics, as well as in the development of effective sensor devices and functional materials. Having a rich history in coordination chemistry, fluorinated β-diketones are well-known ligands generating a wide variety of heterometallic complexes. In this context, we focused on both the synthetic approaches to β-dicarbonyl ligands with additional coordination centers and their possible transformations in complexation reactions. The review describes bi- and polynuclear structures in which β-diketones are the key building blocks in the formation of a heterometallic framework, including the examples of both homo- and heteroleptic complexes. [ABSTRACT FROM AUTHOR]

Synthesis of luminescent metal cluster for selective sensing of specific analyte with detail mechanistic understanding is very important for real world applications as well as for developing new emissive materials. In the present work, we have synthesized L-glutathione stabilized gold (Au-SG) and gold-silver bimetallic (AuAg-SG) clusters under identical experimental conditions with orange red emissive characteristics for both. Detail photo physical analysis reveals that both clusters are phosphorescent in nature with moderate quantum yield of 7% and 19% for Au-SG and AuAg-SG respectively and their excited state lifetime values are in the range of 1–2 μs. While Au-SG cluster showed luminescence quenching response (turn-off) in presence of Fe3+ and Hg2+ ions, AuAg-SG cluster showed turn-off response for Cu2+, Fe3+ and Hg2+, but luminescent enhancement (turn-on) response for Cd2+ ions. The highest detection limit obtained for Cu2+ ion by AuAg-SG cluster is 20 nM while for Cd2+ ion it is 75 nM. From Time Correlated Single Photo Counting (TCSPC) and Dynamic Light Scattering (DLS) measurements we postulated that except Cd2+, all other metal ions cause aggregation of clusters through ligation with SG ligands while Cd2+ ion does not induce any cluster aggregation but binds to cluster surface atoms. The near constant life time values of both clusters during gradual addition of respective metal ions confirms static quenching/enhancement process through formation of stable ground state adducts. [ABSTRACT FROM AUTHOR]

This is a brief research review on the new method of development for element luminescence determination, namely, sonoluminescent spectroscopy. The advantages and disadvantages of the technique of multibubble sonoluminescence (MBSL) in solutions used to apply this method are discussed. It has been shown that the use of a new technique moving single-bubble sonoluminescence (m-SBSL) in colloidal suspensions of nanoparticles (<50 nm) containing the elements analyzed seems preferable for this purpose. This makes it possible to determine elements not only at lower concentrations than when using MBSL in solutions but also to find elements that are unavailable for determination through previous techniques. Thus, this new technique expands the range of elements that can be determined using sonoluminescent spectroscopy. The article provides a detailed description of the standard procedure for the preparation and recording of m-SBSL in colloidal suspensions, as well as examples of characteristic spectra of some elements obtained and recorded for the first time according to this new technique (Al, K, Mn, Cd, Pt, Ni, and Ti), including those not previously found using the MBSL in solutions (Al, Cd, Pt, Ni, and Ti). An example of the analytical line at 396 nm in the Al spectrum obtained through this new technique on the basis of an AlCl3 initial aqueous solution, the region of the linear dependence of the intensity on the AlCl3 concentration was registered, and the lower limit of the spectroscopic determination of the Al content in this solution was estimated as 8.3·10−3 M. Using the analysis of the obtained Cd spectrum as an example, we carried out a spectroscopic measurement of the electronic temperature achieved at m-SBSL in bubble plasma at the moment of greatest compression of a bubble with light emission during its acoustic oscillations in dodecane, Te = 7900 ± 500 K. Graphical Abstract [ABSTRACT FROM AUTHOR]

In this report, we explore the precise responsibility of a phase modifier along with the prime ligand in the coordination process of Ln(III) ions using luminescence spectroscopic technique by taking Eu(III) as the probeing metal ion. A well accepted diglyoclamide (DGA) ligand: N,N,N',N'‐ tetra(ethylhexyl)diglycolamide(T2EHDGA) was used as the prime extractant along with tri‐n‐butylphosphate (TBP) as the phase modifier. Meticulous investigations on Eu(III) complexation with T2EHDGA‐TBP binary mixture was pursued by employing luminescence spectroscopy with the systematic variation of the concentration of TBP in the ligating phase and initial concentration of Eu(III) in the feed phase. The dominancy of the LMCT band over that of the metal centered band signifies the structural difference in the ligands used in the study. The presence of TBP in the organic phase enhances the intensity of 5D0→7F2 and 5D0→7F0 transition. The excitation and emission patterns of the Eu(III)‐solvate species formed in the organic phase both in unirraditaed and irradiated conditions were found to be entirely different, which effectively corroborates the efficacy of the extracting phase. The asymmetry ratio (AR) and the life time data at each experimental conditions were ascertained to realize the coordination behavior of the Eu(III) complex in the organic phase. [ABSTRACT FROM AUTHOR]

A new multi-functional organic–inorganic hybrid compound was successfully obtained by regulating metal halides. Apart from excellent luminescence properties, in particular, the introduction of a Mn halide successfully achieved a dual-switchable dielectric property, which could lead to very interesting exploration in sensors. [ABSTRACT FROM AUTHOR]

We studied the interaction of Cu2+ ions and CuO nanoparticles with the fluorescent Schiff base ligand H3L, which derives from the condensation of 4-formyl-3-hydroxybenzoic acid with N-(2-aminobenzyl)-5-(dimethylamino)naphthalene-1-sulfonamide (DsA). A detailed assignment of the most significant bands of the electronic and infrared spectra of H3L and DsA was performed using DFT methods, based on both crystal structures. The affinity of H3L to react with Cu2+ ions in solution (KB = 9.01 103 L mol−1) is similar to that found for the Cu2+ ions present on the surface of CuO NPs (KB = 9.84 103 L mol−1). Fluorescence spectroscopic measurements suggest five binding sites for H3L on the surface of the CuO NPs used. The µ-XRF analysis indicates that a polycrystalline sample of CuO-H3L NPs contains 15:1 Cu:S molar ratio (CuO:H3L). ATR-FTIR spectroscopy, supported by DFT calculations, showed that the HL2− (as a phenolate and sulfonamide anion) is coordinated to superficial Cu2+ ions of the CuO NPs through their azomethine, sulphonamide, and phenolic groups. A solution of H3L (126 ppb) shows sensitive responses to CuO NPs, with a limit of detection (LOD) of 330 ppb. The working range for detection of CuO NPs with [H3L] = 126 ppb was 1.1–9.5 ppm. Common metal ions in water, such as Na+, K+, Mg2+, Ca2+, Fe3+, and Al3+ species, do not interfere significantly with the detection of CuO NPs. [ABSTRACT FROM AUTHOR]

Dynamics of the population of the excited Ce states responsible for the luminescence response time in Gd3Al2Ga3O12:Ce scintillating crystals is studied by revealing the dynamics of nonequilibrium carriers in the picosecond domain. Optical pump and probe technique exploiting selective excitation of structural units of the crystal and probing the induced absorption as a function of time and spectral position is exploited. A fast response within a few picoseconds due to the absorption by holes at Gd ions and by electrons occupying the first excited state of Ce ions with the intracenter relaxation time of 500 fs are identified. Trapping of nonequilibrium electrons during their migration through the matrix to the emitting Ce ions are shown to be responsible for the slow component in the population of the excited Ce state. Elimination of the slow component is evidenced even at Mg codoping as low as 10 ppm. The elimination correlates with the acceleration of the response in coincidence time resolution experiments showing potential of GAGG:Ce, Mg in medical and high-energy physics applications. [ABSTRACT FROM AUTHOR]

Achieving multi-color luminescence with a single atomic center in transition metal complexes is a challenge. In this work, luminescent materials with tunable emission properties were realized by complexation between aluminum (III) ions with the ligands 3-hydroxyflavone (3-HF) and 5,7-dichloro-8-hydroxyquinoline (DCHQ). Aluminum (III) complexes with a single ligand emitted blue from 3-HF and green from DCHQ. High quantum yields (QYs) of 29.42% and 37.00% were also obtained, respectively. DFT calculations revealed details of the photophysical properties of the complexes. Correspondingly, cyan light emission was obtained if these two complexes were mixed together, from which the emission wavelength was located at 470 nm and the QY was 20.52%, under 290 nm excitation. More importantly, the cyan light emitted by the mixtures had selective sensitivity to different metal ions, resulting in either quenching the fluorescence (in the case of Fe3+) or enhancing the fluorescence (in the case of In3+). The fluorescence enhancement effect of In3+ on metal complexes has not been previously reported, neither for transition metal nor lanthanide ions. The linear quenching behavior of Fe3+ functions in the 50–700 μM concentration range, and the linear enhancement behavior of In3+ is demonstrated in the 300–800 mM concentration range. [ABSTRACT FROM AUTHOR]

We report the first example of very efficient NIR Circularly Polarized Luminescence (CPL) (around 970 nm) in water, obtained thanks to the combined use of a chiral Yb complex and of poly lactic‐co‐glycolic acid (PLGA) nanoparticles. [YbL(tta)2]CH3COO (L=N, N'‐bis(2‐pyridylmethylidene)‐1,2‐(R,R+S,S) cyclohexanediamine and tta=2‐thenoyltrifluoroacetonate) shows good CPL in organic solvents, because the tta ligands efficiently sensitize Yb NIR luminescence and the readily prepared chiral ligand L endows the complex with the necessary dissymmetry. PLGA nanoparticles incorporate the complex and protect the metal ion from the intrusion of solvent molecules, while ensuring biocompatibility, water solubility and stability to the complex. Hydrophilic NIR‐CPL optical probes can find applications in the field of NIR‐CPL bio‐assays. [ABSTRACT FROM AUTHOR]

Utilizing Europium(III), compounds having eight-coordination geometry of the type [Eu(hfpd) 3 L 2 ] and [Eu(hfpd) 3 Lʹ] were synthesized [hfpd = 1,1,1,5,5,5-hexafluoro-2,4-pentanedione, L = tri-octyl-phosphine oxide (TOPO) and Lʹ = 1,10-phenanthroline (phen), Neocuproine (neoc) and bathocuproine (bathoc)] and characterized through elemental, FTIR, CV and Proton-NMR techniques. Photoluminescent studies and quantum yield helped to understand the role of coordination environment and ligands on the emission intensity. Luminescence decay curves served as the basis for calculating the excited-state lifetimes of the synthesized complexes. JO parameters (Ω 2 , Ω 4) and asymmetry ratio were also evaluated to study the coordination environment around the central metal ion. Solid-state complexes exhibited an intense, monochromatic bright red emission, as characterized by its Commission International de l'Eclairage (CIE) color coordinates. Owing to red luminescence and semi-conducting properties, these Eu(III) complexes can be employed as red-emitting material for fabricating lighting devices. [Display omitted] • Octacoordinated luminous Eu(III) complexes were synthesized with hfpd and mono & bidentate ancillary ligands. • Observation of the dominance of the hypersensitive transition 5D 0.→ 7F 2 , indicating asymmetry around Eu(III) ions was supported by intensity ratio analysis. • Calculation of JO parameters provided deeper insight into the asymmetry, rigidity and photophysical characteristics. • Comprehensive characterization, including IR, NMR, CV, UV and colorimetric analysis, support their potential application in photonic devices, sensors, magnets and various technological fields. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission luminogens (AIEgens) offer a timely remedy to tackle aggregation-caused quenching of traditional organic fluorescence probes. Metal–organic frameworks (MOFs) receive tremendous attention due to their easy-to-functionalize surface and tunable porosity. If AIEgens are used to construct MOFs, they are stitched together through coordinate bonds and placed in specific geometric with spatial arrangements. Thus, MOFs are a powerful platform to investigate the underlying AIE mechanism and for luminescent sensing applications. Herein, a symmetrical tetra-carboxylic AIE-active ligand, 2,3,5,6-tetrakis(4-carboxyphenyl)pyrazine (TCPP), was prepared for luminescent MOFs with Fe, Eu, and Cu as metal nodes, separately. During the formation of MOFs, the emission of TCPP was enhanced as coordination-induced emission (CIE) to share the same restriction of intramolecular rotation mechanism to AIE. However, the emission was blue-shifted in the presence of Cu, had a constant wavelength with Fe, and was red-shifted in the Eu–TCPP system. The different emission behaviors of TCPP in different systems revealed the different electronic states and coordination modes of different metal ions. The results also illustrated that the electronic property of the ions affected the luminescence of the MOFs differently. Interestingly, antenna effect emission was observed from Eu–TCPP MOF as dual-emission to study the energy and charge transfer. Considering the stronger emission and high stability of Fe–MOFs than those of Cu–MOFs, Cu–MOFs were used as a probe for the "turn-on" sensing of Fe3+. The combination of AIEgen and MOFs provides a chance to reveal the emission mechanism and develop the sensing application, while CIE is used as the additional evidence for the restriction of intramolecular rotation emission mechanism, the same as AIE. [ABSTRACT FROM AUTHOR]

Six new mixed-ligand bimetallic complexes [Eu2(bz)4(tta)2(phen)2] (1), [Gd2(bz)4(tta)2(phen)2] (2), [EuTb(bz)4(tta)2(phen)2] (3), [EuGd(bz)4(tta)2(phen)2] (4), [Eu1,2Gd0,8(bz)4(tta)2(phen)2] (5) and [Eu1,6Gd0,4(bz)4(tta)2(phen)2] (6) have been prepared with the Eu3+, Gd3+ and Tb3+ ions and the benzoate (bz−), 2-thenoyltrifluoroacetonate (tta−) and the 1,10-phenanthroline (phen) ligands. The compounds combine highly efficient antennas to obtain highly luminescent complexes to enhance solar cell efficiency. The benzoate ligand has been chosen to take its advantage as a bridging ligand to end up with bimetallic complexes to study the effect of combining two metal ions in the luminescent molecule. The structure of 1 was obtained by single-crystal X-ray diffraction, and 1–6 were found to be isostructural by powder X-ray diffraction analysis. The photophysical properties were studied by the absorbance and emission spectra and emission lifetimes. The magnetic properties of 2 were studied, and we found intramolecular antiferromagnetic interactions between the Gd3+ ions. We prepared luminescent down-shifting layers (LDSL) with the 1, 3–6 complexes embedded in ethylene–vinyl–acetate and studied their effect in the external quantum efficiency (EQE) and intensity–voltage (I–V) plots of a solar mini-module. We found that LDSL containing the bimetallic complexes 3 and 6 enhance the efficiency of the solar mini-module from 11.26(3)% to 11.76(4)% (+0.52%) and to 11.44(2)% (+0.21%), respectively. [ABSTRACT FROM AUTHOR]

Multifunctional switching materials show great potential for applications in sensors, smart switches, and other fields due to their ability to integrate different physical channels in one single device. However, multifunctional responsive materials with multiple switching and luminescence properties have rarely been reported. Here, we report three organic–inorganic hybrids: [TMAA]2[CoCl4] (compound 1), [TMAA]2[CdBr4] (compound 2) and [TMAA]2[MnCl4] (compound 3). Compound 1 and compound 2 undergo two reversible phase transitions at high temperature (328.95/359.25 K and 350.45/393.15 K, respectively). Since the inorganic skeleton has a strong influence on the luminescence properties of such structured substances, Cd and Co were replaced with Mn, after which compound 3 was obtained as expected. The above strategy triggered bright green luminescence with a quantum yield of 35.19%, and significantly increased the phase transition temperature of compound 3 to above 400 K. The above results show that the regulation of the inorganic skeleton provides a new strategy for researchers to develop dual phase change/luminous materials. [ABSTRACT FROM AUTHOR]

A lanthanide-based optical sensor has been developed for the sensitive and reliable spectrofluorometric determination of the fluoroquinolone antibiotic orbifloxacin (ORLX). Reaction of ORLX and two lanthanide metal ions, Sm(III) and Tb(III), in aqueous buffered solution produced highly fluorescent complexes. Plackett–Burman design (PBD) was used to explore the impact of four factors, pH, temperature (Temp), contact time (CT), and metal volume (MV), on the fluorescence intensity (FI) of the produced complexes. The obtained data showed that pH was the most significant variable. A blend of pH = 5.0, MV = 2.0 mL, T = 25°C, and CT = 10 min was used to achieve the maximum FI. FT-IR and Raman analyses were performed for the crystals of the as-prepared complexes. Obtained data showed shifting in most of the absorption bands, confirming the complexation of ORLX with both metal ions. Job's method showed that the stoichiometry for the reaction of ORLX with Sm(III) and Tb(III) was 1 : 1. The proposed method was validated following the ICH guidelines. Injection formulation was analyzed successfully with the developed method with high recovery (99.42–100.91%). The detection and quantification limits were 0.987 and 3.289 ng/mL for the ORLX-Sm(III) complex and 1.020 and 3.399 ng/mL for the ORLX-Tb(III) complex, respectively. [ABSTRACT FROM AUTHOR]

• Mononuclear, heterodinuclear and heterohexanuclear complexes were synthesized. • The aliphatic ether Schiff base ligand cannot sensitize terbium ion to luminescence. • The zinc Schiff base complex [ZnL] unit can sensitize terbium ion to luminescence. • The luminescence of terbium complexes can be adjusted by Zn(II) and co-ligand. Three new Tb(III) complexes containing bis(N -3-methoxysalicylidene)-3- oxapentane-1,5-diamine (H 2 L) ligand, [Tb(H 2 L)(NO 3) 3 ] (1), [ZnTbL(NO 3) 2 (OAc)(MeOH)] (2), [Zn 4 Tb 2 L 4 (TP) 2 ](NO 3) 2 ·DMF (3) (DMF = N,N -dimethylformamide, TP = terephthalate) have been synthesized by ether diffusion and structurally characterized. Complex 1 is a mononuclear, whereas complex 2 forms a heterodinuclear Zn-Tb cluster when introducing zinc ion into the reaction system of Complex 1. Complex 3 is a Zn-Tb heterohexanuclear cluster by adding terephthalic acid into the reaction system of complex 2. Solid-state luminescence studies show that the luminescence peaks of the ligand (π*→π) in the three complexes have undergone significant redshift and enhancement, which may be attributed to the coordination of ligand with metal ions. Moreover, the characteristic emission peak of terbium ions (5D 4 →7F 5 , at 545 nm for 2 and 546 nm for 3) appeared in heteronuclear complexes 2 and 3 , while complex 1 did not. This indicates that the aliphatic ether Schiff base ligand cannot sensitize terbium ion to luminescence, while the zinc Schiff base complex [ZnL] unit can sensitize terbium ion to luminescence. Finally, the structures and luminescence properties of terbium complexes can be adjusted by the introduction of zinc(II) ion and co-ligand. [Display omitted] [ABSTRACT FROM AUTHOR]

• Coordination sphere effects: Spectroscopic analysis of samarium β-diketonate complexes. • Emission peak at 648 nm: Electric dipole transition responsible for characteristic orange-red emission. • Spectroscopic evidence confirms octacoordinated samarium ion with carbonyl oxygen and nitrogen coordination. • Semiconducting properties and good thermal stability suggested display applications. Ternary Sm(III) complexes of general representation [Sm(TFDH) 3 L] were synthesized to understand influence of different auxiliary moieties on their optoelectronic properties. The synthesized complexes were thoroughly investigated using elemental, IR, NMR, UV and PL studies. In these complexes, the emitting metal ion is bonded with six O atoms from di-ketone 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione and two nitrogen atoms from neutral ligand i.e. 1,10-phenanthroline and its derivatives. Proton NMR spectral data showed that samarium ion induced chemical shift is dipolar in nature. The photoluminescence analysis showed that the complexes show intense orange-red emission due to 4G 5/2 → 6H 9/2 transition. Moreover, CIE color coordinates supported the results obtained from photoluminescence study, providing additional confirmation of the luminescent properties of prepared complexes within the orange-red region. Their utility in displays and OLED's was confirmed by studying their optical and electronic band gaps. [Display omitted] [ABSTRACT FROM AUTHOR]

• The CA-BPE -based co-crystal probe shows selective enhanced fluorescence with Al3+ ions in MeOH: H 2 O (2:8, v/v). • The CA-BPE forms a 1:1 stoichiometry complex with an association constant of 9.17 × 104 M−1. • The CA-BPE detects Al3+ down to 30.4 nM with a pH range of 3 to 6 without interfering form other cations. • Binding mechanism between CA-BPE with Al3+ was studied by FTIR, PXRD, SEM, EDX, and DFT studies. Herein, the caffeic acid and bipyridyl ethylene-based co-crystal (CA-BPE) have been developed as a fluorescent turn-on sensor for Al3+ ions in MeOH: H 2 O (8:2, v/v) media. The free CA-BPE co-crystal shows an absorbance band at 297 nm and emission at 445 nm. The probe forms a 1:1 stoichiometry complex with an estimated association constant of 9.17 × 104 M−1 by Job's and BH plots, respectively. The CA-BPE detects Al3+ down to 30.4 nM with a pH range of 3 to 6 without interfering with other metal ions. Further, the binding mechanism between CA-BPE and Al3+ was studied by FTIR and DFT studies. Interestingly, the PXRD, SEM, EDX, and DFT-based computational studies reveal the formation of 2D layers of a metal–organic framework (MOF)-like structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • CPL Instrumentation has been modified across the three generations; in order to achieve precisely accurate results. • Methodology in order to evaluate the characteristics of circularly polarized luminescence. • Factors that influence and enhance the CPL properties of coordination complexes. • How CPL-active materials can be utilized. The effective production and application of materials with circularly polarized luminescence (CPL) has emerged as a cutting-edge field of research in a number of areas. Researchers should prioritize establishing a high luminescence dissymmetry factor (g lum) and optimizing the optical performance of CPL to meet the needs of practical applications in a wide range of domains. This has led to the foundation of a vast array of new CPL resources and ways to address these important issues. Here, we offer a concise summary of current advancements in the study, development, and application of circularly polarized luminous materials. The numerous methods used to characterize and quantify circularly polarized light, such as circularly polarized luminescence and circular dichroism, are described logically. Secondly, we will discuss the environmental conditions that can influence CPL activity, including temperature, time, pH, solvents, mechanical force, and metal ions. In addition, we present a brief summary of how CPL-active materials have been utilized in several sectors, including organic LEDs, probes and sensors, CPL contrast imaging, and photodetectors. Lastly, this new field's current potential and challenges are evaluated. This review is intended to serve as a guide for anyone seeking to design high-quality CPL-active materials. [ABSTRACT FROM AUTHOR]

In recent years, environmental issues have been caused by heavy metals, which have not been effectively resolved. Fluorescent materials are being used as promising detectors. Covalent organic frameworks (COFs) possess excellent porosity that provides extensive space for guest molecule. The turntable skeleton is also a crucial factor in designing the target site for capturing them. In this study, the hydrazone-based crystalline H–COF-1 and H–COF-2 were successfully synthesized through a solvothermal process. Their luminescence activities are controlled from blue to green for H–COF-1 and H–COF-2 due to the turntable conjugated sites on the walls. More specifically, the intramolecular hydrogen between the ortho-hydroxyl group and imine bond constructs the conjugations binding site of H–COF-2. H–COF-2 possesses more interacted sites for metal ions and demonstrates efficient fluorescence quenching for Cu2+ at 85 % in water, surpassing the performance of H–COF-1. The selectivity and detection limits were also significantly improved as a result. The turntable sites present a novel design approach for luminescent materials as chemical sensors. [Display omitted] • The turntable conjugated strategy regulates luminescence form bule to green for H-COFs. • The H–COF-2 indicates high fluorescence quenching efficiency for Cu2+ at 85 % in water. • The turntable sites on the walls of H–COF-2 also improve the selectivity and detection limits of Cu2+. [ABSTRACT FROM AUTHOR]

• Co-doping with alkaline-earth (AE2+) elements enhances the photoluminescence properties of Mn2+-doped CsPbCl 3 nanocrystals. • Introduction of small AE2+ ions into the doping process induces lattice contraction in Mn2+-doped CsPbCl 3 nanocrystals, leading to improved photoluminescence quantum yield and photostability. • The co-doping of Sr2+ ions with Mn2+ in CsPbCl 3 nanocrystals demonstrates a remarkable enhancement in luminescence and light-emitting diode performance. Doping Mn2+ into CsPbCl 3 nanocrystals (NCs) has garnered significant attention for its potential to create tailored optical properties in optoelectronic applications. However, this approach still faces challenges, including low photoluminescence quantum yield (PL QY), suboptimal Mn2+ doping efficiency, and inadequate stability. Herein, we delve into the specific realm of Mn2+ doping in CsPbCl 3 NCs and delve into the effects of co-doping these NCs with alkaline earth (AE2+) metal ions. Through a comprehensive characterization of the co-doped NCs, we systematically unravel bonding characteristics, and luminescence behaviors induced by AE2+ co-doping. The outcomes underscore the notable enhancement in luminescence performance and stability achieved through AE2+ co-doping, particularly with Sr2+. The utilization of smaller AE2+ results in lattice contraction, leading to improved PL QY and heightened photostability. This work offers valuable insights into tailoring the performance of transition metal-doped semiconductor NCs for advanced optoelectronic devices, establishing a foundation for subsequent optimization and diverse applications. The enhancement in luminescence performance and stability of Mn2+ doped CsPbCl 3 nanocrystals achieved through alkaline-earth (AE2+) metal ions co-doping. [Display omitted] [ABSTRACT FROM AUTHOR]

Ce-PA-Tb polymer with Ce and Tb as metal ion centers was prepared and applied in chemiluminescence (CL) reaction. The structure and property of Ce-PA-Tb were explored. Ce-PA-Tb combines both the oxidant ion (Ce(IV)) and luminescence ion (Tb(III)). Difloxacin can enhance the CL signal of Ce-PA-Tb-SO 3 2- reaction in acidic medium. Under the optimized affecting factors, a CL method for the selective difloxacin determination was established. The CL intensity showed a good linear relationship from 10.0 to 300.0 μg/L (r = 0.9996) with the limit of detection was 1.1 μg/L. The method with the signal response at 0.5 s and completed the CL process within 10 s. The method was used to determine difloxacin in aquatic products, and the recovery rate was in the range of 88.1%–104.0%. The CL method designed Ce-PA-Tb based is demonstrated to be an excellent tool for difloxacin determination in aquatic products. A chemiluminescence method for the determination of difloxacin in aquatic products was developed based on Ce-PA-Tb-SO 3 2-. The chemiluminescence reaction mechanism of difloxacin-Ce-PA-Tb-SO 3 2- was discussed. [Display omitted] • Ce-PA-Tb polymer prepared for chemiluminescence reaction. • The reaction mechanism of difloxacin-Ce-PA-Tb-SO 3 2- explored. • A chemiluminescence method for difloxacin determination developed. • The chemiluminescence method applied to difloxacin analysis in aquatic products. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ratiometric luminescence probe was proposed for the detection Cu2+ and Fe3+. • Cu2+ and Fe3+ quench the luminescence of MOF through different mechanisms. • Comparing with Fe3+, Cu2+ enhances the quenching efficiency of MOF through a combination of inner filter effect and energy transfer. • The intensity ratios of the Tb3+ and ligands show opposite trends with the rise of Cu2+ or Fe3+ concentration. The development of probes for the detection of multiple heavy metal ions holds the nonnegligible practical significance for ensuring public and environment safety. In this work, a ratiometric luminescence probe was proposed for the detection Cu2+ and Fe3+ based lanthanide metal–organic framework@polyethyleneimine (Ln-MOF@PEI). The formation of the complexes between PEI and Cu2+ enhances the quenching efficiency of MOF through a combination of inner filter effect and energy transfer, surpassing the observed quenching efficiency with Fe3+. The emission intensity ratio between Tb3+ and the ligands exhibits a decreasing trend with increasing Cu2+ concentration, while it rises with increasing Fe3+ concentration. It allows for the discrimination between Cu2+ and Fe3+ based on their distinct quenching mechanisms. The assay performance of Ln-MOF@PEI probes was evaluated comprehensively. The limit of detection for Cu2+ and Fe3+ reaches at 9.7 nM and 37.4 nM, respectively. The probe demonstrates acceptable selectivity by effectively avoiding interference from common cations and anions. The detection range covers a wide concentration range from nanomoles to millimoles. Overall, the luminescence probe is expected to meet the requirements of accurate quantification for Cu2+ and Fe3+ in the various application scenarios. [ABSTRACT FROM AUTHOR]

Developing highly sensitive MOF-based probes for environmental contaminant detection is of much importance and challenging. Here, two new three-dimensional lanthanide metal–organic frameworks (Ln-MOFs), {[Eu(DTA)1.5(H2O)]·H2O}n (Eu-DTA) and [Tb(DTA)(C2O4)0.5(H2O)]n (Tb-DTA) (H2DTA = 2,5-di(1H-imidazol-1-yl)terephthalic acid), are successfully synthesized via a hydrothermal reaction. Single-crystal X-ray diffraction analyses demonstrate that the extended π conjugated ligand plays an important role in the coordination mode and topologies. Eu-DTA possesses a 4,6-connected three-dimensional topological structure, while Tb-DTA exhibits a 4,5-connected three-dimensional framework. Interestingly, the rich uncoordinated nitrogen or oxygen atoms in these two structures can be used as Lewis basic sites, showing strong sensitivity to metal ions and solvent molecules. Furthermore, luminescence and sensing studies reveal that Eu-DTA and Tb-DTA can sensitively and simultaneously detect Fe3+ ions and nitrobenzene, which suggests that the two Ln-MOFs are promising bifunctional luminescence sensors. The quenching mechanism for Fe3+ has been discussed in detail. [ABSTRACT FROM AUTHOR]

Nanopowders of ytterbium-doped yttrium aluminum garnet are synthesized by the polymer–salt method and their crystal structure and spectral-luminescent properties are studied experimentally. The IR spectroscopy data of the materials synthesized are presented. X-ray diffraction analysis revealed that ytterbium-doped yttrium aluminum garnet nanocrystals 18–35 nm in size are formed at 900–1100°С. Study of the spectra and luminescence decay kinetics showed that the properties of the synthesized nanocrystals are close to the characteristics of macroscopic materials synthesized by traditional high-temperature methods. [ABSTRACT FROM AUTHOR]

Using a convenient high-temperature solid-state method, a novel Zn(W–Mo)O 4 red phosphor co-doped with alkaline metal ions and Eu3+ was successfully synthesized. The effects of doping with one charge-compensating agent and mixed multiple charge-compensating agents on the phase composition, crystal structure, crystallinity and luminescence properties of phosphors were studied. Using a theoretical study, the crystal environment around the Eu3+ ion was analysed and the internal quantum yield was calculated. The charge-compensating agent decreases the non-radiative transition by reducing the Zn defect in the phosphor and simultaneously changes the crystal environment around the Eu3+ ions. The enhancement of luminescence intensity of phosphors by co-doping with different charge-compensating agent ions is consistent with single doping. The luminescence intensity was increased 82.64% by doping with a charge-compensating agent, and the colour purity increased to 90.36%, indicating that the Zn(W–Mo)O 4 :Eu3+ red phosphor can be used as a potential candidate material in white-light-emitting diodes. [ABSTRACT FROM AUTHOR]

We report the facile synthesis of TbIII and EuIII adducts able to elicit circularly polarized luminescence. Both the sensitization of the lanthanide‐ion‐centered luminescence (i. e. the antenna effect) and the chiral environment around the metal ions are brought about by commercially available enantiopure 2,6‐bis(oxazolinyl)pyridine ligands (PyBox). This strategy is promising for the development of a wide range of new and simple circularly polarized luminescence (CPL) active LnIII adducts, thanks to the fine tunability of the chemical structure of the PyBox ligands. [ABSTRACT FROM AUTHOR]

A new porous metal-organic framework, [Pb5(OAc)7(nIm)3]n (1), has been successfully synthesized by employing 2-nitroimidazole ligand and Pb2+ ion. 1 contains novel the ribbon-shaped Pb-O SBU and reveals a 2D porous framework with a 1D tubular channel. Due to the existence of the electronegative O atom of nitro group and Lewis acid metal ion in the channel, 1 shows moderate CO2 adsorption uptake of 25.8 cm3 cm− 1 at 298 K and 760 mmHg, and adsorption sites are also confirmed by GCMC simulations. Moreover, the electronic structures and luminescence properties of 1 was investigated. This work displays an effective approach to enrich multifunctional porous Pb-MOFs. [ABSTRACT FROM AUTHOR]

With increasing industrial development, heavy metal ions have been widely released, and fluorescence detection is an effective approach owing to its high selectivity and sensitivity. Herein, a water-soluble luminescent sensor based on a spirobifluorene-based imidazolium polymer (IMSPF-Br-COOH) is developed from tetraimidazole spirobifluorene and 3-bromo-2-bromomethylpropionic acid through a quaternization reaction. IMSPF-Br-COOH has an imidazolium cationic network and carboxyl coordination groups. Consequently, fluorescence quenching of IMSPF-Br-COOH exhibits high selectivity for Fe3+ and Cr2O72−via coordination and anion exchange. The corresponding quenching coefficient (Ksv) is 2.0772 × 103 L mol−1 for Fe3+ and 1.0081 × 104 L mol−1 for Cr2O72−. The detection limit (LOD) is calculated to be 170.56 μmol L−1 for Fe3+ and 100.81 μmol L−1 for Cr2O72−. This work provides a novel approach for metal ion detection by water-soluble polymers. [ABSTRACT FROM AUTHOR]

Zn(II) and Cd(II) coordination polymers constructed from a new angular bis-pyridyl-bis-amide ligand and naphthalene-1,4-dicarboxylic acid (1,4-H2NDC), {[Zn2(L)(1,4-NDC)2]·2H2O} [L = 4,4′-oxybis(N-(pyridin-3-ylmethyl)benzamide)], 1, and {[Cd2(L)(1,4-NDC)2]·EtOH}, 2, have been solvothermally synthesized and structurally characterized by using single-crystal X-ray diffraction. While complex 1 displays a 2D double layer with the rare (46·64)-5 L4 topology, complex 2 shows a 3D framework with a new (4·5·6)(45·55·69·7·8) topology. Both complexes 1 and 2 display luminescence properties and 2 exhibits a high sensitivity toward the detection of Fe3+ ions with a Ksv value of 1.9 × 104 M−1. The quenching effect can most probably be ascribed to the interactions between the metal ions and the amide carbonyl oxygen atoms. [ABSTRACT FROM AUTHOR]

Two series of terbium complexes of Tb2(4‐BMBA)6(phen)2 (Tb−Br, 4‐BMBA=4‐Br‐3‐methylbenzoic acid, phen=1,10‐phenanthroline) and Tb2(4‐IMBA)6(phen)2 (Tb−I, 4‐IMBA=4‐I‐3‐methylbenzoic acid) are synthesized by varying the single factor of electron‐acceptor property of substituent group Br and I at para‐position of 3‐methylbenzoic acid. They crystalize in the same space group, ligand and metal ions are arranged in the same mode. Interestingly, the luminescence quantum yield (QY) of Tb−Br is greater than Tb−I, indicating that weaker electron‐acceptor group of I at para‐position of 3‐methylbenzoic acid leads to lower luminescence QY than Br in terbium complex. This is the first work to control the single variable factor to study the substituent group property on the luminescence QY of lanthanide complex. Further study reveals that Tb−I is a multiplex sensor for Fe2+, Co2+, and Ni2+. [ABSTRACT FROM AUTHOR]

Detection of metals in different environments with high selectivity and specificity is one of the prerequisites of the fight against environmental pollution with these elements. Pyrenes are well suited for the fluorescence sensing in different media. The applied sensing principle typically relies on the formation of intra‐ and intermolecular excimers, which is however limiting the sensitivity range due to masking of e. g. quenching effects by the excimer emission. Herein we report a highly selective, structurally rigid chemical sensor based on the monomer fluorescence of pyrene moieties bearing triazole groups. This sensor can quantitatively detect Cu2+, Pb2+ and Hg2+ in organic solvents over a broad concentrations range, even in the presence of ubiquitous ions such as Na+, K+, Ca2+ and Mg2+. The strongly emissive sensor's fluorescence with a long lifetime of 165 ns is quenched by a 1 : 1 complex formation upon addition of metal ions in acetonitrile. Upon addition of a tenfold excess of the metal ion to the sensor, agglomerates with a diameter of about 3 nm are formed. Due to complex interactions in the system, conventional linear correlations are not observed for all concentrations. Therefore, a critical comparison between the conventional Job plot interpretation, the method of Benesi‐Hildebrand, and a non‐linear fit is presented. The reported system enables the specific and robust sensing of medically and environmentally relevant ions in the health‐relevant nM range and could be used e. g. for the monitoring of the respective ions in waste streams. [ABSTRACT FROM AUTHOR]