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Although considerable research works have witnessed the important modulations of oxygen vacancies on the optical, electrical, and magnetic properties of SnO 2 nanostructures, it is not easy to control oxygen vacancy defects in such systems.The difficulty stems from that oxygen vacancy is a kind of atomic defect, and its distribution is sensitive to process conditions and external factors, which makes direct characterization and purposeful control difficult. The purpose of this work on Ce-doped SnO 2 nanocrystals is to investigate the tolerance of the host lattice to Ce ions, the population and evolution of Ce3+/Ce4+ ions, and the possibility to adjust oxygen vacancies by Ce3+ ions, and then focus on the influence of oxygen vacancy defects on the band gap and luminescence performance. As Ce doping concentration increases from 0 to 12 at.%, the doped system changes from Ce3+ dominated at low doping amount (≤3 at.%) to Ce3+/Ce4+ coexistence at medium doping concentration (3 at.% ∼ 9 at.%), to occurrence of CeO 2 impurity phase at over doping (∼12 at.%). The optimum doping occurs at 6 at.%, which corresponds to the saturated critical point of Ce3+ content and the maximum oxygen vacancy concentration. Importantly, the oxygen vacancies in the current Ce-doped SnO 2 nanocrystals is directly regulated by the Ce3+ ion concentration on the Sn sites, which plays an important role in the band gap tuning and visible light emission. With Ce concentration increasing from 0 to 12 at.%, the band gap monotonicity decreases from 3.36 eV to 3.12 eV, while the intensity of the oxygen vacancy luminescence band first increases and then decreases, with the turning point at 6 at.%. Both band gap narrowing effect and enhanced emission indicate that Ce-doped SnO 2 should be a promising method to design and manufacture visible light responsive SnO 2 based optoelectronic materials by manipulating oxygen vacancy defects. [ABSTRACT FROM AUTHOR]

• Improvement of downconversion luminescence by adjusting the co-doping ratio of Yb3+ and Er3+ in NaLuF 4 :Yb3+,Er3+ micrometer prismatic crystals. • Defects in the crystals were removed by treating the microcrystals with ion exchange and high-temperature annealing methods to further improve the downconversion luminescence performance. • The crystalline quality and densification of the treated crystals were enhanced, and the diffraction peaks were closer to those of standard β-NaLuF 4. • The downconversion luminescence of the treated sample was significantly enhanced, and its luminescence intensity could reach 2.5 times of that of the untreated sample. NaLuF 4 :Yb3+,Er3+ micrometer prismatic crystals are potential materials for the preparation of optical waveguide devices. However, structural defects and OH– groups are generated inside and on their surfaces during growth processes. The structural defects and OH– groups lead to a large depletion of excitation energy and severely quench the downconversion luminescence of Er3+. In addition, the Yb3+/Er3+ co-doping ratio significantly affects the downconversion luminescence of the microcrystals, which in turn affects the performance of the optical waveguide amplifiers based on the microcrystals. By adjusting the co-doping ratio of Yb3+ and Er3+ in the microcrystals and removing the defects in the crystals, their downconversion luminescence performance was significantly improved. The results showed that the downconversion luminescence under the excitation from a 980 nm laser reached the maximum value when the doping ratio of Yb3+ and Er3+ was 20:1.5. In addition, the OH– groups and structural defects in the micrometer crystals were significantly eliminated by ion-exchange and high-temperature annealing treatments, and the crystalline quality was significantly improved. After ion-exchange and high-temperature annealing treatments, the downconversion luminescence enhancement of NaLuF 4 :Yb3+,Er3+ microcrystals was 2.5 times that of the untreated samples. By changing the Yb3+/Er3+ co-doping ratio in the NaLuF 4 :Yb3+/Er3+ crystals, a clear pattern exists between the down-conversion luminescence and the co-doping ratio of the samples. Meanwhile, the lattice defects and OH– groups in the crystals can be removed by ion exchange and high-temperature annealing methods, which can further enhance the down-conversion luminescence. By observing the scanning electron micrographs before and after the reaction, it can be found that the size and surface morphology of the samples have changed greatly, and the crystalline quality and densification of the crystals of the treated samples have been improved. The XRD diffraction peaks of the treated sample (110) are shifted to a large angle, which is closer to β-NaLuF 4. Meanwhile, the upconversion luminescence, downconversion luminescence, and downconversion energy level lifetimes of the samples before and after the treatment can be found to be significantly changed under the excitation at 980 nm. [Display omitted] [ABSTRACT FROM AUTHOR]

SrF 2 transparent ceramic is a promising upconversion material due to the low phonon energy. The effect of different sintering temperatures on Er:SrF 2 transparent ceramics was investigated. The suitable sintering temperature for Er:SrF 2 transparent ceramics was 900 °C by hot-pressed sintering in this study. High quality of Er:SrF 2 transparent ceramics with different doping concentrations were obtained. The upconversion luminescence spectra and decay behavior were compared between Er:SrF 2 and Er:CaF 2 transparent ceramics with different Er3+ doping concentration. The green emission of 5 at.% Er:SrF 2 ceramic was much stronger than that of 5 at.% Er:CaF 2 ceramic, while the red emission of Er:SrF 2 ceramic was almost the same as that of Er:CaF 2 ceramic. The upconversion luminescence lifetime of Er:SrF 2 transparent ceramics was longer than that of Er:CaF 2.All the results indicated Er:SrF 2 transparent ceramics was a candidate for green fluorescent upconversion materials. [ABSTRACT FROM AUTHOR]

Self‐assembly of transition metal ions with different N‐donor ligands and 3,3′‐azodibenzoic acid (3,3′‐H2ADB) yielded five novel metal‐organic frameworks. All the 3,3′‐ADB2– anions got oxidized into 3,3′‐AO2DB2– and 3,3′‐AODB2– under solvothermal conditions. Compound 1 has a 3D 6‐connected pcu architecture based on [Mn3(COO)6] SBU. Compound 2 exhibits 3D threefold interpenetrating framework based on paddlewheel [Mn2(COO)4] SBU with 41263 topological configuration. Compound 3 bears zigzag double chains, which are then connected by π–π stacking interactions into 2D porous structure. Compound 4 features 2D network with self‐penetrating feature. Compound 5 exhibits a fivefold interpenetrating architecture with dia type. Magnetic measurements show that 1, 2 and 5 exhibit antiferromagnetic behavior. In addition, compound 3 displays significant adsorption towards methylene blue in aqueous solution. Thermogravimetric analyses for 1–5 and the luminescence properties of 3 and 4 have also been investigated. [ABSTRACT FROM AUTHOR]

High optical quality of Er3+:CaF 2 transparent ceramics were successfully fabricated by hot pressing method. The maximum transmittance reached to 93% which was close to theoretical transmittance in 2 mol% Er3+:CaF 2 transparent ceramics. The upconversion luminescence of ceramics samples were investigated in detail upon 980 ​nm, 808 ​nm excitation and 980 ​nm ​+ ​808 ​nm two-wavelength excitation, respectively. UC transition mechanism about red emission at 808 ​nm excitation was different from that at 980 ​nm excitation. Owing to the synergistic effect at simultaneous 980 ​nm and 808 ​nm excitation, energy losses caused by multi-phonon relaxation and the energy mismatch between 4f levels and excited photons could be suppressed. The strategy of multi-wavelength excitation might broaden the applications of upcoversion ceramics materials. [ABSTRACT FROM AUTHOR]

Polymer-based waveguide amplifiers are essential components in integrated optical systems, as their gain bandwidths directly determine the operating wavelength of optical circuits. However, development of the wideband gain media has been challenging, making it difficult to fabricate devices with broadband amplification capability. Rare earth ion-doped nanoparticles (NPs) are a key component in the gain media, and their full width at half maximum (FWHM) of the emission peak decides the final gain bandwidth of the gain media. Here, KMnF3: Yb, Er, Ce@KMnF3: Yb NPs with the broad full width at half maximum (FWHM) of the emission peak covering the S+C band was prepared. The NPs were synthesized using a hydrothermal method, and the FWHM of the emission peak of NPs reached 76 nm under the excitation of a 980 nm laser. The introduction of Ce3+ ions and a core-shell structure coating greatly enhanced the emission intensity of NPs at C band. Since KMnF3: Yb, Er, Ce@KMnF3: Yb NPs have exceptional broadband luminescence properties at C band, KMnF3: Yb, Er, Ce@KMnF3: Yb NPs can be the potential gain medium in the future polymer-based waveguide amplifiers. [ABSTRACT FROM AUTHOR]

A photoresponsive hollow molecularly imprinted polymer (PHMIP) was fabricated for photoresponsive recognition and determination of trace bisphenol A (BPA) in aqueous media using a water-soluble azo compound as the functional monomer. The PHMIP was prepared on sacrificial silica microspheres by surface imprinting and subsequent removal of the silica core. The PHMIP displayed photocontrolled recognition for BPA. SEM, TEM, FT-IR, TGA and N 2 adsorption-desorption analyses confirmed successful formation of the hollow structure. The PHMIP displayed higher binding capacity, a larger specific area, and faster mass transfer rate than its corresponding surface molecularly imprinted polymer. The PHMIP was used to determine trace BPA in real samples with a limit of detection of 0.5 ppm. For samples spiked at 0–10 ppm, the BPA recoveries were in the range of 93.0%–99.0%. This PHMIP-based method provides convenient and inexpensive detection method for trace BPA in environmental samples. This method is especially suitable for determining materials that do not possess specific spectroscopic or luminescent properties. [ABSTRACT FROM AUTHOR]

We reported on an Yb/Tb-codoped silica fiber with a large fiber core prepared from nanoporous silica glass based on glass phase-separated method. The measured refractive index profile indicated an excellent homogeneity of the doped active fiber core. Intense green upconversion emission from Tb centered at 543 nm was obtained in the Yb/Tb-codoped silica fiber under 976-nm excitation. It is suggested that the green upconversion emission is dominated by a two-photon absorption process. It is found that the Al ions as a modifier can facilitate the energy transfer from Yb to Tb in the porous glass fiber. The energy transfer efficiency from Yb to Tb was calculated. [ABSTRACT FROM AUTHOR]

Two type lanthanide complexes obtained by salen-type ligand N,N'-ethylenebis(salicylideneimine) (HL) and N,N'-ethylene-bis(3-methoxysalicylideneimine) (HL) have been isolated. They are 2D coordination polymer [Yb(HL)(NO)] ( 1), mononuclear Ln(HL)(NO) [Ln = Sm ( 2), Ho ( 3)]. The structures of 1- 3 were determined by single crystal X-ray crystallographic studies and their photophysical properties were investigated. [ABSTRACT FROM AUTHOR]

Three dinuclear lanthanide complexes are achieved by using H2salen or H2salen/acac ligands (H2salen = N,N′-ethylenebis(salicylideneimine), acac = acetylacetonate). They are homodinuclear [Er2(salen)3] (1), [Yb2(salen)2(acac)2] (2), and heterodinuclear geometrical [ErYb(salen)2(acac)2] (3). The structures of complexes were determined by single crystal X-ray crystallographic studies and their photophysical properties were investigated. The homonuclear Yb2 complex exhibits characteristic metal-centered NIR emission. The geometric ErYb isomer exhibits ‘dual emissions’ from both erbium(iii) and ytterbium(iii) ions. There was no detectable photoluminescence in the Er2 complex, not only in solid state but also in solvent. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the near-infrared luminescence emission of erbium ions is enhanced by 6-folds in intensity with an ion-associated erbium complex consisting of an IR140 dye cation. The energy-transfer process from the IR140 dye cation to the erbium ion has been modeled. Near-infrared luminescence of the erbium ion is sensitized intra-molecularly by the IR140 dye cation effectively, although the residual IR140 dye emission is still observed, indicating an incomplete energy transfer between the IR140 dye cation and the erbium ion. The main path of energy-transfer process is through the T1 → 4I11/2 transition with the operative mechanism to be Förster type. [Copyright &y& Elsevier]

Abstract: Two novel metal–organic frameworks of [M3(ptz)2(N3)4(H2O)2] (M=Zn(1), Cd(2)) (ptz=5-(4-pyridyl)tetrazolate) have been prepared hydro(solvo)thermally by reactions of 4-cyanopyridine and excess NaN3 in the presence of zinc and cadmium chloride, respectively. The overall structure motif of complexes 1 and 2 show pillared layered frameworks and feature an unprecedented 3-nodal network with (3,5,6)-connectivity. The layer is of particular interest as it is constructed by μ1,1–N3 − and μ1,1,3–N3 − bridging modes, simultaneously. Furthermore, the solid fluorescent properties and TGA were studied. [Copyright &y& Elsevier]

Abstract: This paper reports a highly efficient organic light-emitting diode (OLED) with high-quality white emission that employs a deep blue-emitting beryllium complex bis(2-(2-hydroxyphenyl)-pyridine)beryllium (Bepp2) doped with a wide-bandwidth orange-emitting fluorescent dye 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4-H-pyran (DCM) through incomplete energy transfer from the blue host to the orange dopant. The two-component WOLED exhibits ideal and stable CIE coordinates (0.334±0.002, 0.337±0.007) with a high color rendering index equal to 79–81 upon variation in brightness from 10 to 10,000cdm−2. As an all-fluorophore-doped white OLED, it yields very high EL efficiencies with the peak luminescence efficiency. The peak value of luminescence efficiency (LE), power efficiency (PE), and external quantum efficiency (EQE) is 14.0±0.35cdA−1, 9.2±0.25lmW−1, and 5.6±0.15%, respectively. [Copyright &y& Elsevier]

Flow cytometry (FC) was used to determine effects of tetrabromobisphenol A (TBBPA) on the green alga Chlorella pyrenoidosa (C. pyrenoidosa) by evaluating esterase activity, membrane integrity, concentrations of intracellular reactive oxygen species (ROS) and chlorophyll a (Chl-a) auto-fluorescence. TBBPA can inhibit esterase activity. Esterase activity was inversely proportional with TBBPA with a 24 h EC50 value of 3.13 mg TBBPA/L. After 48 h of exposure to TBBPA intracellular ROS was significantly greater than in the unexposed cells. TBBPA inhibited Chl-a fluorescence after 168 h. Concentrations of ROS were directly proportional to both magnitude and duration of exposure and was inversely proportional to cellular Chl-a. FC was useful as an integrated, ecologically relevant, measure of a functional response of the algae. The possible action pathway of TBBPA in C. pyrenoidosa is that TBBPA can cause toxic effects on esterase activity. As concentrations and exposure time increased, TBBPA change the ROS level in the internal. The role of anti-oxidative action is marked and significant at the duration of 48 h exposure, compared to the control. This suggested there was a redox cycle. TBBPA changes physiological status of cells, further decreased Chl-a fluorescence indicating inhibition. [ABSTRACT FROM AUTHOR]

Abstract: Rare earth ternary chelates Ln(TFA)3(TPPO)2 (Ln=Eu, Tb and Eu/Tb) were synthesized in gel glasses via in situ technique. Pure Ln(TFA)3(TPPO)2 chelates were also synthesized for a comparative study. Photoluminescence properties of the in situ chelates in gel glasses and the pure chelates were studied. In order to investigate the energy transfer mechanism from Tb3+ ions to Eu3+ ions in Eu/Tb(TFA)3(TPPO)2 chelates, photoluminescence spectra and fluorescence decay curves have been measured at the temperature range from 10K to 293K. It is found that the energy transfer rate constants calculated from the fluorescence lifetimes do not vary with temperature, which suggests that Dexter mechanism is responsible for the energy transfer from Tb3+ ions to Eu3+ ions in both pure and in situ Eu/Tb ternary chelate. [Copyright &y& Elsevier]

Abstract: Laser dyes such as coumarin 440 (C440) and coumarin 500 (C500) were doped into vinyltriethoxysilane (VTES)-derived organically modified silicates (ORMOSILs) by sol–gel process. The fluorescence properties of these two dyes doped in VTES-derived ORMOSILs with various initial dye concentrations were studied. A longitudinal pumped solid-state dye laser was established with a Q-switched Nd:YAG laser source. The laser performances of C440 and C500 dyes doped in VTES-derived ORMOSILs were also measured. [Copyright &y& Elsevier]

A novel unexpected 1D coordination polymer Nd(Nphgly)(1,2-BDC)(H2O)·2H2O (1) containing simultaneously N-phthaloylglycine (Nphgly) and benzene-1,2-dicarboxylic acid (1,2-BDC) ligands has been prepared under the solvothermal conditions. In situ solvothermal aminolysis reaction occurred at benzene-1,2-dicarboxylic acid and glycine when they reacted with neodymium salts. Furthermore, the magnetic and luminescent properties of 1 were studied. [ABSTRACT FROM AUTHOR]

SrLaGa 3 O 7 :Eu3+ and SrLaGa 3 O 7 :Tb3+ fluorescent powders were synthesized using solid sintering procedure. The crystal structure and luminescence of the synthesized fluorescent powders were surveyed. XRD patterns of the synthesized fluorescent powders demonstrate that they have the single tetragonal phase. Under excitation at 392 nm, SrLaGa 3 O 7 :Eu3+ fluorescent powders exhibit photoluminescence bands rooting in 5D 0 → 7F 0, 1, 2, 3, 4 transitions of Eu3+. In SrLaGa 3 O 7 , La3+ ions are surrounded octahedrally by eight ions and there is only one mirror plane paralleling to c axis in these distorted octahedrons. This characteristic induces the existence of photoluminescence band resulting from 5D 0 → 7F 0 transition and the strongest photoluminescence band resulting from 5D 0 → 7F 2 transition. Under excitation at 265 nm, SrLaGa 3 O 7 :Tb3+ fluorescent powders show photoluminescence bands resulting from 5D 3 → 7F 3 and 5D 4 → 7F 6, 5, 4, 3 transitions of Tb3+. The band resulting from 5D 4 → 7F 5 transition is strongest because that this transition has the largest probability for both electric-dipole and magnetic-dipole transitions. The decay curves of SrLaGa 3 O 7 :Eu3+ and SrLaGa 3 O 7 :Tb3+ fluorescent powders show a single exponential characteristic. • Synthesis of Eu3+/Tb3+ doped SrLaGa 3 O 7. • Single tetragonal phase of synthesized Eu3+/Tb3+ doped SrLaGa 3 O 7. • Red/green light emitted by Eu3+/Tb3+ doped SrLaGa 3 O 7. [ABSTRACT FROM AUTHOR]

Copper is an essential mineral nutrient for the human body. However, excessive levels of copper accumulated in the body can cause some diseases. Therefore, it is great significant to establish a sensitive bioprobe to recognize copper ions (Cu2+) in vivo. In our work, nitrogen-doped carbon dots (N-CDs) and gold nanoclusters (Au NCs) are selected as luminescent nanomaterials and the Au NCs/N- CDs nanohybrids is successfully synthesized by coupling method. The Au NCs/N-CDs exhibited characteristic dual-emission peaks at 450 and 620 nm when excited by a single-wavelength of 380 nm. When different amounts of Cu2+ are introduced, the fluorescence intensity of the Au NCs is gradually weakened and fluorescence intensity of the N-CDs is almost unchanged, which can facilitate the visual detection of Cu2+. The Au NCs/N-CDs nanohybrid possesses good selectivity to Cu2+ with a limit of detection (LOD) is 3.5 μM and linear detection range of 10–150 μM. Visualization detection of Cu2+ is implemented by using nanoprobe in water samples. Furthermore, the ratiometric nanoprobe is utilized to the toxicity test of liver cancer cells, indicating excellent biocompatibility and low toxicity. This nanoprobe has been used to the intracellular fluorescence imaging. Moreover, this method is expected to be used to monitor the changes of Cu2+ concentration in hepatocytes. Unlabelled Image • A dual-emission nanohybrid of the Au NCs/N-CDs was prepared. • The nanoprobe exhibited high sensitivity and selectivity to Cu2+. • This method was used to analysis of Cu2+in real water samples. • The nanoprobe was utilized to the monitoring and imaging of Cu2+ in HepG2 cells. [ABSTRACT FROM AUTHOR]

In this paper, cyan BaLaGa 3 O 7 : Bi3+ phosphors were synthesized by solid-state reaction method at 1400 °C. The crystal structure, elemental composition and optical properties were characterized and studied. The results of X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy and infrared spectroscopy indicate the successful synthesis of BaLaGa 3 O 7 : Bi3+ phosphors with the pure phase. The BaLaGa 3 O 7 : Bi3+ phosphors show wide band emission corresponding to the 3P 1 →1S 0 transition of Bi3+ when excited at 328 nm. • Synthesis of the BaLaGa 3 O 7 :Bi3+ phosphors. • Broadband cyan emission of the BaLaGa 3 O 7 :Bi3+ phosphors. • Excellent thermal stability of the BaLaGa 3 O 7 :Bi3+ phosphors. [ABSTRACT FROM AUTHOR]

A hydrogen‐bonded solvate (HBS) model is herein proposed to construct hydrogen‐bonded organic frameworks (HOFs), for enhancing the solid‐state one‐/two‐photon excited fluorescence (1/2PEF) of organic fluorophores. Two photonic HOFs (ZJU‐HOF‐25 and ZJU‐HOF‐26) are synthesized by using the same organic fluorophore and the fluorophore in them features similar arrangement. The most obvious structural distinction between the two HOFs is the existence of solvent molecules in the crystal cell of ZJU‐HOF‐25. ZJU‐HOF‐25 is regarded as an ideal HBS material where solvent molecules separate fluorophores apart just like dissolving them. But ZJU‐HOF‐26 contains no solvent molecules and the fluorophores are connected directly via hydrogen bonds among them. A significant quantum yield (η) increase is realized from amorphous fluorophores (η ≈0%) to HBS‐based ZJU‐HOF‐25 (η ≈21.75%), while ZJU‐HOF‐26 displays poor 1PEF (η ≈0%). ZJU‐HOF‐25 also exhibits much stronger 2PEF with the two‐photon action cross section larger than ZJU‐HOF‐26 by almost two orders of magnitude. These phenomena are mainly attributed to that the solvent molecules in ZJU‐HOF‐25 benefit the homogeneous separation and conformation fixation of fluorophores, suppressing the non‐radiative transition. The HBS model thus shows the fantastic validity to improve solid‐state optical properties of organic materials, providing guidance for exploring advanced optical materials. [ABSTRACT FROM AUTHOR]

Herein, a series of ionic mononuclear Cu(I) complexes, [Cu(phen)(bdppmapy)]Cl (1a), [Cu(phen)(bdppmapy)]Br (2a), [Cu(phen)(bdppmapy)]I (3a), [Cu(phen)(bdppmapy)]SCN (4a), [Cu(Dpq)(bdppmapy)]Cl (1b), [Cu(Dpq)(bdppmapy)]Br (2b), [Cu(Dpq)(bdppmapy)]I (3b) and [Cu(Dpq)(bdppmapy)]SCN (4b) {phen = [1,10]phenanthroline; Dpq = pyrazino[2,3-f][1,10]-phenanthroline; bdppmapy = N,N-bis((diphenylphosphino)methyl)-2-pyridinamine} have been synthesized and characterized by using IR, NMR, elemental analysis, single crystal X-ray diffraction analysis, fluorescence spectroscopy methods, and UV-vis and terahertz (THz) time-domain absorption spectroscopy. Their crystal structures were elucidated by X-ray crystallography and their photophysical properties were investigated in detail. All the above complexes exhibit a 1D to 3D supramolecular structure which is linked together by intermolecular weak interaction forces and hydrogen bonds. By regulating ligands and anions, the emission wavelengths of these complexes are quite different in the range from 533 nm to 604 nm. Theoretical calculations and photophysical properties indicate that luminescence is derived from metal-to-ligand charge transfer (MLCT) excited states. In the meantime, the results of calculations show that the stabilization of the increased conjugation of the ligand-based π* orbital is ascribed to the observed bathochromic-shift in the MLCT transitions. [ABSTRACT FROM AUTHOR]

Luminescence characteristics of yttrium-aluminum garnet based phosphor samples differed by their elemental composition and prehistory of synthesis are studied. The morphology, structure, and elemental composition of phosphor samples, their excitation and emission spectra, efficiency of phosphor conversion of chip emission, and kinetics of luminescence decay are measured. The emission characteristics of phosphors are compared with their structural properties and elemental composition. [ABSTRACT FROM AUTHOR]

• A well-designed multilayer core–shell UCNPs for generating orthogonal RGB luminescence with high color purity is proposed. • A simple approach for modulation of full-color upconversion luminescence in such UCNPs is introduced. • The display matrices based on UCNPs/epoxy AB glue can improve color pixel and optical resolution of color display. • The naked-eye-based volumetric/flat color display images with high color pixel and optical resolution can be achieved. Real three-dimensional (3D) volumetric display, as a pursuable ultimate goal in the field of display, have attracted extensive interest in both fundamental research and various frontier applications. In particular, the emergence of solid-state 3D display technology based on upconversion processes offers a versatile and powerful tool to achieve truly spatial naked-eye 3D displays. However, the realization of a solid-state real 3D volumetric color display with high spatiotemporal resolution in upconversion nanoparticles (UCNPs) at a single nanoparticle level remains a great challenge. Herein, without multiple compositions of UCNPs and high excitation power density or complex pulse excitation modulation, a specifically well-designed nanostructures of multilayer core–shell UCNPs, by manipulating energy transfer pathways, enables us to realize excitation power density-independent orthogonal red–green–blue (RGB) emissions with high color purity by utilizing near-infrared multiwavelength excitations. Notably, full-color emissions, involving red, orange, yellow, green, blue, indigo, violet, and white upconversion luminescence, can be dynamically regulated in this multilayer architecture by adjusting excitation wavelength and power density of the combined 980/808/1560 nm lasers. These emission profiles of multilayer UCNPs make them promising for a wide range of applications. As a proof of concept, we demonstrated their potential for application in real 3D volumetric full-color display. By incorporating such UCNPs into epoxy resin AB glue to construct transparent display matrices, the naked-eye-based 3D volumetric color display images with high color pixel and optical resolution can be achieved by moving the focal point of the laser beams within the stereo display matrices. These findings will benefit the future development of convenient and versatile optical technique for the fine tuning of full-color luminescence in a single nanoparticle level, and provide the possibility to construct true 3D volumetric full-color display technologies with high brightness, nanometer range display resolution, and multi-perspective display. [ABSTRACT FROM AUTHOR]

The cyan SrLaGa 3 O 7 :Bi3+ phosphors were prepared via the solid state sintering processes at 1400 °C. The optical performance was characterized and researched based on the theory calculation and experimental results. The phase and constitution of the prepared SrLaGa 3 O 7 :Bi3+ phosphors were ascertained by the X-ray diffraction and elemental composition analyses. The theory calculations were carried out based on the state density function. Upon the ultraviolet light excitation, SrLaGa 3 O 7 :Bi3+ phosphors yield broadband emission in 380–600 nm relating to the 3P 1 →1S 0 transitions of Bi3+. The full width of the half-maximum of emission band reaches ∼130 nm. Tunable light was achieved by adjusting the content of Bi3+ or changing the excitation wavelength. [Display omitted] • Synthesis of disordered SrLaGa 3 O 7 :Bi3+ phosphor with a wide cyan emission band. • Dependence of emission on excitation wavelength and doping concentration. • Influence of disordered structure on the luminescence of the phosphor. [ABSTRACT FROM AUTHOR]

Herein, six new [Cu(N^N)(P^P)]+/0 complexes with different N-ligands and counteranions, [Cu2(dmp)2(bdppmapy)I2] (1), [Cu2(dmp)2(bdppmapy)(CN)2]·3CH3OH (2), [Cu(dmp)(bdppmapy)](BF4) (3), [Cu(dmp)(bdppmapy)](ClO4) (4), [Cu(phen)(bdppmapy)](BF4) (5), and [Cu(phen)(bdppmapy)](ClO4) (6), have been synthesized and characterized (bdppmapy = N,N-bis[(diphenylphosphino)methyl]-2-pyridinamine, phen = 1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline). Single-crystal X-ray diffraction showed that different counteranions help to construct various stacking modes 1D–3D via weak interactions, such as π–π, C–H⋯π and C–H⋯X (X = F, O). Photophysical analysis showed they have yellow-green to yellow-orange emission within a range of 504–569 nm, and excellent photophysical properties with quantum yields from 2.6% (2) to 77% (4). In this study, these results indicate that the π–π stacking and C–H⋯X (X = O, F) weak interactions help to enhance the rigidity of these structures and further improve their luminescence quantum yields. In addition, we have explored the nature of the complexes emission mechanism through theoretical calculations. According to DFT/TD-DFT calculations, the luminescence behavior of the six complexes is ascribed to MLCT or (M + X)LCT. THz spectra were applied to explore the relationship between weak interactions and luminescence. These results have opened up a new direction in the characterization of the properties of luminescent materials. [ABSTRACT FROM AUTHOR]

Traditional inorganic ceramic materials usually exhibit macroscopic rigidity due to the incompatibility to the flexibility mechanism of traditional flexible materials such as sliding of polymer chains or atoms. Recently, new form of nanotechnology has been proposed to be capable of preparing inorganic flexible materials. In this paper, inorganic luminescent material (Ba,Ca)TiO 3 :Pr3+ was prepared into the flexible form by electrospinning technology, and the macroscopic flexibility of pure inorganic (Ba,Ca)TiO 3 :Pr3+ was systematic investigated. The crystal grain size was found to grow after higher temperature calcination, which benefits luminescence. However, lowering the calcination temperature will further optimize the flexibility of the membrane. This study shows that fibrous membrane fabrication is an applicable flexible fabrication strategy for inorganic oxides, which provides an important reference for the design of flexible materials. • Macroscopically self-supporting flexible (Ba,Ca)TiO3:Pr3+ nanofiber membranes were prepared for the first time. • The prepared macroscopic self-supporting flexible (Ba,Ca)TiO3:Pr3+ nanofiber membranes were characterized by a bending stress test system. • The macroscopically flexible nanofiber membrane is inorganic. • The macroscopically flexible inorganic nanofiber membrane has excellent luminescence properties. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), self-assembled from metal ions with organic ligands, are well known for their intriguing framework topology, permanent porosity, and tunable optical properties and have shown great promise for a good number of applications. Over the past few years, luminescent MOFs have attracted growing attention, especially for developing various luminescent sensors, by virtue of their excellent selectivity and high sensitivity. In this feature article, we highlight some of the recent significant progress in this active research field, and provide a comprehensive review on luminescent MOFs as sensory materials for diverse sensing applications including for metal ions, anions, small molecules and gases, nitroaromatics and explosives, temperature, as well as other aspects. [ABSTRACT FROM AUTHOR]

Colloidal perovskite quantum dots (CsPbX 3) are highly desirable in optoelectronics due to their favorable optical properties. However, their instability limits their practical application. This study investigates the use of metal-organic frameworks as carrier matrices for perovskite quantum dots, which could enhance their stability without compromising their optical properties. Here, CsPbBr 3 @ZIF-8 composite materials were synthesized through an in-situ growth method. The results demonstrate that the CsPbBr 3 quantum dots in the composite exhibit a significantly longer lifetime (increasing from 11 ns to 39 ns), higher quantum yield (increasing from 32 % to 53 %) compared to pure perovskite quantum dots. The photothermal stability of the composite is also superior to that of the pure quantum dots, as the composite maintains 81 % of its quantum yield under light, 82 % under wet air, and 72.5 % under continuous heating at 120 °C. Furthermore, the CsPbBr 3 @ZIF-8 based flexible fluorescent film shows adjustable viscosity, which provides a novel approach for next-generation flexible displays. • In situ growth of perovskite quantum dots in ZIF-8. • Use ZIF-8 to improve the optical properties of materials. • With PDMS to prepare flexible film-expanded solution materials. [ABSTRACT FROM AUTHOR]

The luminescence properties of the tetranuclear bimetallic lanthanide complexes Sm2Eu2 ( 1) and Eu2Tb2 ( 2), were compared with those of the analogous homometallic complexes [Sm4(μ3-OH)2(salen)2(acac)6(CH3OH)2] ·CH3OH ( 3) and [Eu4(μ3-OH)2(salen)2(acac)6(CH3OH)2] ( 4) [H2salen = N, N′-ethylenebis(salicylideneimine), Hacac = acetylacetonate]. X-ray crystallographic analysis reveals that complexes 3 and 4 have planar tetranuclear structures. For the Eu2Tb2 configurational isomer, the TbIII ion in complex 2 mainly serves as a sensitizer. The quantum yields and lifetime measurements for 2 support the premise that Ln/ Ln energy transfer occurs in such lanthanide bimetallic complexes, along with the usual ligand-to-metal triplet energy pathways. Complexes 3 and 4 exhibit the characteristic metal-centered emission. [ABSTRACT FROM AUTHOR]

All-inorganic CsPbBr3 perovskites exhibit great potential in optoelectronic application due to their outstanding physical properties for optoelectronics. However, the relatively low luminescence efficiency of the bulk CsPbBr3 crystal hampers its further application. Here, we report a facile method to enhance the optical efficiency of halide perovskite powder via doping the transition metal Ni ions. It is demonstrated that Ni doping results in the formation of the Cs(NiPb)Br3 alloy and also triggers the phase transition of CsPbBr3 from orthorhombic to cubic. Both the Cs(NiPb)Br3 alloy and cubic CsPbBr3 are found to contribute to the asymmetric photoluminescence (PL) spectra in the green-yellow light band. The splitting-peak fitting experiments for the overlapped PL spectrum based on the bi-Gaussian line model reveal that the Cs(NiPb)Br3 alloy dominates the contribution of the observed PL enhancement. The Ni2+ doping is also beneficial for optimizing the crystallinity of the CsPbBr3 perovskite, suppressing the nonradiative recombination and significantly enhancing the photoluminescence consequently. Our investigation provides a novel insight into the effect of environmentally friendly metal doping in perovskites. [ABSTRACT FROM AUTHOR]

On the basis of the 3-(pyrazin-2-yl)-1H-pyrazole-5-carboxylic acid (H2L) ligand, four new polymers [Cu2(L2−)2] (1), [Zn3(L2−)2(H2O)4Cl2]n (2), [Pb(HL−)Cl]n (3), and {[Ni(L2−)(H2O)]·(H2O)}n (4) have been synthesized under solvothermal conditions. Polymer 1 possesses a discrete (0D) binuclear structure, which is further formed into a three-dimensional (3D) supramolecular structure by hydrogen bonding and π⋯π stacking interactions. Polymers 2 and 3 display one-dimensional (1D) infinite chain structures, which further extend into 3D supramolecular structures through hydrogen bonding interactions. Polymer 4 features two-dimensional (2D) layers which can form a 3D supramolecular architecture via interlayer hydrogen bonds. The ligand in the four polymers adopts different coordination modes for constructing versatile structures. Moreover, luminescence sensing study shows that polymer 2 is a promising luminescent sensor for the detection of Cu2+, Co2+ and Fe3+via drastic luminescence quenching in aqueous solution with high efficiency. The quenching constants KSV for Cu2+, Co2+ and Fe3+ are 6.35 × 103 M−1, 8.70 × 103 M−1 and 1.62 × 104 M−1, respectively. What's more, 1–4 with electrochemical luminescence (ECL) properties show high intensity in N,N-dimethylformamide (DMF) solution and high thermal stability. [ABSTRACT FROM AUTHOR]

Nine lanthanide complexes with a high L:Ln ratio (4:1), [LnL 4 ](OTf) 3 ( 1 – 8 ) (L = tetrakis( O -isopropyl)methylenediphosphonate, OTf = SO 3 CF 3 , Ln = Ce, Pr, Nd, Sm, Eu, Gd, Dy, Yb) and [DyL 4 ](OTf) 3 ·DMF ( 9 ) have been synthesized through easy and effective methods in air. Each complex was synthesized by the reaction of lanthanide triflate with the L ligand in a solvent mixture (acetonitrile and DMF for 1 – 8 , dichloromethane and DMF for 9 ). The above complexes, except for complex 9 , were synthesized in the presence of 1,10-phenanthroline. The title complexes were characterized by elemental analyses, IR spectra, single-crystal X-ray diffraction analysis, luminescence, NMR spectra and terahertz time-domain spectroscopy (THz-TDS). Structure analysis shows that complexes 1 – 9 consist of one cation [LnL 4 ] 3+ and three triflate anions OTf - . Complexes 1 – 8 crystallized in the orthorhombic system, space group Pbcn , whereas complex 9 belongs to the space group I 222. The cationic [LnL 4 ] 3+ fragments in complexes 1 – 8 are self-assembled to construct 2D layers with a (8·2·8·4) net topology by hydrogen bonding interactions. The OTf − cations in 9 are attached directly to the [DyL 4 ] 3+ cations to form a 2-fold hydrogen-bonded three-dimensional (3D) cage structure framework. Solid luminescence of complex 5 displays the characteristic bands of Eu 3+ , due to a long emission lifetime (4.04 ms of 5 D 0 ) and high absolute emission quantum yield (53.30%). Terahertz (THz) time-domain spectroscopy of the complexes was also studied. [ABSTRACT FROM AUTHOR]

In acidic solution, a serials of water-soluble coordination polymers (CPs) were isolated as zonal 1D-CPs 1,3-propanediaminetetraacetato lanthanides [ Ln (1,3-H 3 pdta)(H 2 O) 5 ] n ·2Cl n ·3 n H 2 O [ Ln =La, 1 ; Ce, 2 ; Pr, 3 ; Nd, 4 ; Sm, 5 ] (1,3-H 4 pdta=1,3-propanediaminetetraacetic acid, C 11 H 18 N 2 O 8 ) in high yields. When 1 eq. mol potassium hydroxide was added to the solutions of 1D-CPs, respectively, two 1D-CPs [Ln(1,3-H 2 pdta)(H 2 O) 3 ] n ·Cl n ·2 n H 2 O [ Ln =Sm, 6 ; Gd, 7 ] were isolated at room temperature and seven 2D-CPs [ Ln (1,3-H 2 pdta)(H 2 O) 2 ] n ·Cl n ·2 n H 2 O [ Ln =La, 8 ; Ce, 9 ; Pr, 10 ; Nd, 11 ; Sm, 12 ; Eu, 13 ; Gd, 14 ] were isolated at 70 °C. When the crystals of 1–4 were hydrothermally heated at 180 °C with 1–2 eq. mol potassium hydroxide, four 3D-CPs [ Ln (1,3-Hpdta)] n · n H 2 O [ Ln =La, 15 ; Ce, 16 ; Pr, 17 ; Nd, 18 ] were obtained. The two 2D-CPs [ Ln (1,3-Hpdta)(H 2 O)] n ·4 n H 2 O (Sm, 19 ; Eu, 20 ) were isolated in similar reaction conditions. With the increments of pH value in the solution and reaction temperature, the structure becomes more complicated. 1–5 are soluble in water and 1 was traced by solution 13 C{ 1 H} NMR technique, the water-soluble lanthanides 1 and 5 show catalytic activity to ester hydrolysis reaction respectively, which indicate their important roles in the hydrolytic reaction. The europium complexes 13 and 20 show visible fluorescence at an excitation of 394 nm. The structure diversity is mainly caused by the variation of coordinated ligand in different pH values and lanthanide contraction effect. Acidic conditions are favorable for the isolations of lanthanide complexes in different structures and this may helpful to separate different lanthanides. The thermal stability investigations reveal that acidic condition is favorable to obtain the oxides at a lower temperature. [ABSTRACT FROM AUTHOR]

In this paper, a series of Eu3+/Tb3+ doped La3Ga5SiO14 (LGS:Eu3+, Tb3+) phosphors with excellent performance have been synthesized by high-temperature solid-phase method. The effects of Eu3+ and Tb3+ doping in LGS on the host lattice were analyzed by X-ray diffraction (XRD). X-ray photoelectron spectroscopy (XPS) proved that the Eu3+ and Tb3+ ions were successfully doped into the LGS host. The doped Eu3+/Tb3+ ions only occupy the eight-coordinated La3+ sites. The concentration quenching points of LGS:Eu3+ and LGS:Tb3+ phosphors were determined to be 0.16 and 0.18, respectively. The luminescence performance and fluorescence lifetime of LGS:Eu3+, Tb3+ were studied. LGS:Eu3+, Tb3+ phosphors successfully realized Tb3+ → Eu3+ energy transfer to enhance Eu3+ luminescence. The energy transfer mechanism is speculated on using the experimental results. The energy transfer efficiency from Tb3+ to Eu3+ is about 66.83% in La2.46Tb0.18Eu0.36Ga5SiO14. The LGS:Eu3+, Tb3+ phosphors can achieve tunable luminescence by controlling the doping concentrations of Eu3+ and Tb3+. The ΔE is calculated to be 0.2567 eV for the La2.70Eu0.12Tb0.18Ga5SiO14 phosphor. [ABSTRACT FROM AUTHOR]

The development of a convenient method for the discrimination of typically quenching metal ions such as Cu2+, Co2+, Ni2+, and Fe3+ is of great interest but still a challenge. By simultaneously incorporating Eu3+ and organic dye 3,3′‐diethyloxacarbocyanine iodide (DOC) into a metal‐organic framework, MOF‐253, a luminescent sensor array MOF‐253⊃Eu3++DOC with three emission centers is generated. Utilizing the diversity of quenching responses of metal ions to the different emission centers, five metal ions including Ag+, Cu2+, Fe3+, Co2+ and Ni2+ can be well distinguished with a discrimination accuracy of 100% at a concentration as low as 60 µm. Subsequently, the binary and ternary mixtures of three metal ions (Fe3+, Co2+, and Ni2+) can also be discriminated successfully. Furthermore, taking Cu2+ and Ag+ as examples, this MOF‐based sensor array can quantify the ion concentration at a low range from 0 to 15 µm. Most probably, this is the first case of simultaneous recognition and quantitation of metal ions in an aqueous solution using an MOF‐based luminescent sensor array. Since a variety of luminescent species including organic dyes and lanthanide ions can be introduced into MOFs to generate multiple‐dimensional luminescence, such strategy will open a new avenue for luminescent sensor assays. [ABSTRACT FROM AUTHOR]

The synthesis of four heteroleptic dinuclear Cu(I) complexes bearing tetraphosphine and diimine ligands was reported. Complexes 1–3 were successfully obtained through microwave synthesis while complex 4 was synthesized through traditionally stirring at room temperature. These complexes are listed as follows: [Cu2(Dpq)2(dppeda)](ClO4)2·1.5CH2Cl2 (1), [Cu2(neo)2(dppeda)](ClO4)2·1.3CH2Cl2·1.7C4H10O (2), [Cu2(batho)2(dppeda)](ClO4)2·C4H10O (3), and [Cu2(batho)2(dpppda)](ClO4)2·3CH2Cl2 (4) {(Dpq = pyrazino[2,3-f][1,10]phenanthroline, batho = 4,7-diphenyl-1,10-phenanthroline, neo = 2,9-dimethyl-1,10-phenanthroline, dppeda = N1,N1,N2,N2-tetrakis[(diphenylphosphino)methyl]-1,2-ethanediamine, and dpppda = N1,N1,N4,N4-tetrakis[(diphenylphosphino)methyl]-1,4-benzenediamine}. Their crystal structures have been elucidated by X-ray crystallography and their photophysical properties have been investigated in detail. Photophysical studies and time domain density functional theory (TD-DFT) calculations show that the luminescence performance of these four complexes is ascribed to metal-to-ligand charge transfer (MLCT) mixed with ligand-to-ligand charge transfer (LLCT), and complex 2 shows green emission at 574 nm with the highest quantum yield of up to 52.80%. In addition, the research of photoluminescence properties under the guidance of terahertz spectroscopy technology leads to the preliminary discovery of a correlation between crystal packing and luminescence. It is found that the terahertz spectrum and absorption peak are strongly interdependent on C–H⋯π and π⋯π interactions, and the external weak interactions have negative effects on the luminescence performance. Herein, we predict that the terahertz spectroscopy analysis establishes a bridge between weak interactions (C–H⋯π and π⋯π interactions) and the photoluminescence properties, and puts forward a problem that should be noticed in designing Cu(I) complexes. [ABSTRACT FROM AUTHOR]

Abstract: The present work is focused on the enhancement of luminescence in PbWO4 by boron (B) ions doping. A series of boron-doped PbWO4 polycrystals were synthesized by solid-state reaction in air atmosphere. The crystal structure of PbWO4 was decided from powder X-ray diffraction data. The X-ray excited luminescence, UV excitation and emission spectra measurements were conducted on these samples under the same conditions to evaluate the doping effects of luminescence on PbWO4. The B-doped PbWO4 gave an enhanced broad emission band centered between 420 and 520 nm depending on different doping concentration. Another scintillating crystal, Bi4Ge3O12, was also introduced to compare the effects of luminescence with B-doped PbWO4. The doping mechanism of B ions in the PbWO4 lattices was briefly discussed according to the present experimental results. [Copyright &y& Elsevier]

Different copper(I) complexes were synthesized by changing the anions and ligands. All complexes show 0D−3D structures which are caused by intermolecular interactions such as hydrogen bonds, C H⋯π interactions and π⋯π interactions. The luminescence properties of complexes are generated by metal-to-ligand charge transfer (MLCT). In addition, THz time-domain spectroscopy was also studied in this research. Nine novel copper(I) complexes with diphosphine and diimine ligands, namely [Cu(dpq)(xantphos)]BF 4 (1), [Cu(dpq)(xantphos)]I (2), [Cu(dpq)(dppp)]BF 4 (3), [Cu(dppz)(dppp)]BF 4 (4), [Cu(dppz)(dppp)]I (5), [Cu(dppz)(pop)]I (6), [Cu(dpq)(pop)]I (7), [Cu(dpq)(pop)]Br (8), [Cu(dpq)(pop)]SCN (9) (dpq = pyrazino[2,3-f][1,10]phenanthroline, dppz = dipyrido[3,2-a:2′,3′-c]phenazine, xantphos = 9,9-dimethyl-4,5-bis(diphenylphosphanyl)xanthene, dppp = 1,3-bis(diphenylphosphino)propane, pop = 1,1′-[(Oxydi-2,1-phenylene)]bis[1,1-diphenylphosphine]), were characterized by single crystal X-ray diffraction, IR, elemental analysis, 1H NMR, 31P NMR, fluorescence spectra and terahertz time domain spectroscopy (THz-TDS). These nine complexes were synthesized by the reactions of copper salts, diimine ligands and various of P-donor ligands through one-pot method. Single crystal X-ray diffraction reveals that complex 9 is of a simple mono-nuclear structure while complexes 6 and 7 are of dimer structures. For complex 8 , hydrogen bonds and C H⋯π interactions lead to the formation of a 1D infinite chain structure. Interestingly, complexes 1 – 5 show novel 2D or 3D network structures through C H⋯π interactions. In addition, complexes 1 – 3 and 6 – 9 exhibit interesting fluorescence in the solid state at room temperature. Among the nine complexes, complex 1 shows the highest quantum yield up to 37% and the lifetime of 1 is 6.0 μs. The terahertz (THz) time-domain spectra of these complexes were also studied. [ABSTRACT FROM AUTHOR]

Abstract A silica composite system with rare earth ions and gold nanoparticles was fabricated based on nanoporous silica glass. The formation and optical properties of the systems were controlled by the nanoparticles doping concentration and heat treatment. The luminescence intensity dependence on the HAuCl 4 doping concentration and heat-treated temperature were investigated. At the optimized concentration of HAuCl 4 and heat-treated temperature, the maximal luminescence intensity can be enhanced up to 14.33-fold for Yb2+ and 10.52-fold for Eu2+. It is indicated that the rare earth ions luminescence can be regulated by interactions distance between different types of RE ions and metal NPs as well as the state of nanopores. [ABSTRACT FROM AUTHOR]

Graphical abstract Reactions of diphosphine and diimine ligands with AgCF 3 SO 3 under different reaction conditions gave rise to six complexes with different structures. The representative one-dimensional coordination polymer {[Ag(dppe)(dmp)](CF 3 SO 3)·(CH 3 OH)·(H 2 O)} n exhibited good stability and excellent catalytic activity toward the photodegradation of a spectrum of common organic dyes in water under UV light irradiation. Abstract Six new silver(I) complexes with diphosphine ligands and 1,10-phenanthroline derivatives are named by [Ag 2 (dppe)(dicnq) 2 ](CF 3 SO 3) 2 (1), [Ag 2 (dppp) 2 (dicnq) 2 ](CF 3 SO 3) 2 (2), [Ag 2 (dppb) 2 (dicnq) 2 ](CF 3 SO 3) 2 (3), [Ag(DPEphos)(dicnq)]CF 3 SO 3 (4), {[Ag(dppe)(dmp)](CF 3 SO 3)·(CH 3 OH)·(H 2 O)} n (5), [Ag 2 (dppp) 2 (dmp) 2 ](CF 3 SO 3) 2 ·(H 2 O) (6), (dppe = 1,2-bis(diphenylphosphino)ethane, dppp = 1,3-bis(diphenylphosphino)propane, dppb = 1,4-bis(diphenylphosphino)butane, DPEphos = bis[2-(diphenylphosphanyl)phenyl]ether, dmp = 2,9-dimethyl-1,10-phenanthroline, dicnq = 6,7-dicyanodipyridoquinoxaline) were characterized by IR and X-ray diffraction. Further fluorescence spectroscopy, photocatalytic properties and terahertz time-domain spectra (THz-TDS) were performed on 2 – 6. Complexes 1 – 3 and 6 were binuclear, while 4 was mononuclear. Complex 5 was a coordination polymer, displaying a one-dimensional infinite chain. Moreover, complexes 1 , 2 and 4 were assembled via several pairs of C H⋯π interactions to 1D–3D supramolecular architectures. The emission peaks of the complexes 2 – 4 all exhibit a large degree of red shift, which may be tentatively attributed to the intraligand transition. Compounds 2 – 6 represented the first examples of Ag(I) complexes bearing both diphosphine and diimine ligands that exhibit high, efficient photocatalytic abilities for dye degradation under UV light and show good stability toward photocatalysis. [ABSTRACT FROM AUTHOR]

A trinuclear cyanide-bridged luminescent compound, trans-RuII(DMAP)4(CN)2[(PY5Me2)Mn]2[PF6]4 (1-R), and its oxidation product, ferromagnetic trans-RuIII(DMAP)4(CN)2[(PY5Me2)Mn]2-[PF6]5 (1-O), were synthesized and fully characterized. This is the first example of a molecular material showing a redox-controlled transformation between fluorescence and ferromagnetism. [ABSTRACT FROM AUTHOR]

The rapid development of functionalization of lanthanide metal organic frameworks (Ln-MOFs) offers the potential for biomarkers sensing. It is closely associated with biology science and clinic medicine. In this work, a porous and luminescent terbium metal-organic framework TbTATB has been designed and solvothermally synthesized. The PXRD results demonstrated the commendable stability of this sensor. Enhanced luminescence of TbTATB origin from Tb 3+ was observed in the presence of Zn 2+ , which is a kind of biologically important ion. This turn-on pattern was utilized for sensing Zn 2+ . TbTATB exhibited excellent sensitivity and selectivity towards Zn 2+ in aqueous solution with the detection limit of 10.5 nM. What's more, it has fairly acceptable biocompatibility which was fully verified by cytotoxicity test. In the state of coexistence with living cells, visible increased green light of TbTATB emerged after the addition of Zn 2+ , while the survival state of cells was hardly disturbed. Markedly, this is the first time that a luminescent Tb-MOF can act as a sensor for sensing and imaging of Zn 2+ ions simultaneously. What's more, the results also guide a new application direction of MOFs and supply a new way for the detection of other analytes in biological systems. [ABSTRACT FROM AUTHOR]

A fluorescent pH sensor based on post-synthetically modified nanoscale UiO-67-bpydc by encapsulating Eu 3+ cations in the pores was fabricated. The Eu 3+ incorporated sample (Eu 3+ @UiO-67-bpydc) shows excellent luminescence due to the sensitization and protection provided by the parented framework. Subsequently, Eu 3+ @UiO-67-bpydc was developed as a pH sensor. Eu 3+ @UiO-67-bpydc shows good chemical resistance to both acidity and alkalinity solutions with pH ranging from 1.06 to 10.99, which makes it potentially useful for wide-range pH sensor. In addition, cycling experiments have demonstrated the utilizability of the sensor. The MTT analysis shows that Eu 3+ @UiO-67-bpydc possesses favourable biocompatibility. Furthermore, fluorescence imaging of Eu 3+ @UiO-67-bpydc in PC12 cells was also performed to test its feasibility in vivo. Given its exceptional stability and pH-dependent fluorescent intensity, the fluorescent probe should be a promising candidate for application in fluorescent pH sensing in vitro and in vivo. [ABSTRACT FROM AUTHOR]

The reactions of diphosphine ligands and nitrogen-containing ligands with Cu(I) salts in the mixed solvents of methanol (MeOH) and dichloromethane (CH 2 Cl 2 ) generated the corresponding complexes, {[Cu(dppbe)(Bphen)](ClO 4 )·2CH 3 OH} n ( 1 ), {[Cu 2 (dppe)(dmp) 2 (CN) 2 ]·2CH 3 OH} n ( 2 ), {[Cu 2 (dppb)(dmp) 2 I 2 ]·2CH 3 OH} n ( 3 ), [Cu(POP)(C 16 H 6 N 6 )]I ( 4 ), {[Cu(POP)(C 16 H 6 N 6 )](SCN)} n ( 5 ), [Cu(xantphos)(bpy)](ClO 4 ) ( 6 ) and {[Cu(xantphos)(bpy)](CF 3 SO 3 )} n ( 7 ) {dppbe = 1,2-bis(diphenylphosphanyl)benzene, dppe = 1,2-bis(diphenylphosphino)ethane; dppb = 1,4-bis(diphenylphosphino)butane, POP = bis[2-(diphenylphosphino)phenyl]ether, xantphos = 4,5-bis (diphenylphosphio)-9,9-dimethylxanthene, Bphen = 4,7-diphenyl-1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline, C 16 H 6 N 6 = [2,3-f]-pyrazino-[1,10]phenanthroline-2,3-dicarbonitrile, bpy = 2,2′-bipyridine}. These complexes were all characterized by single-crystal X-ray crystallography, elemental analysis, IR, 1 H NMR spectroscopy, luminescence and THz spectroscopy. Complexes 1 and 2 consist of 1D infinite zigzag chain structures which are linked by hydrogen bonds, while complexes 3 , 5 and 7 have 2D topological architectures which are connected by hydrogen bonds, complex 4 has an annular structure and complex 6 is a mononuclear structure. The types of hydrogen bonds, choice of solvents and coordination modes of the ligands are of importance in defining the structural and topological features of the resulting networks. Furthermore, complexes 1 – 7 exhibit interesting luminescence in the solid state at room temperature. Complexes 1 – 3 can act as yellow luminophores, complex 4 acts as a red luminophore, complex 5 acts as an orange luminophore and complexes 6 – 7 act as green luminophores. Their terahertz spectra show more accurate characteristics of their structures. [ABSTRACT FROM AUTHOR]

Five mono-nuclear silver (I) complexes with 6,7-dicyanodipyridoquinoxaline ligand, namely {[Ag(DPEphos)(dicnq)]NO3}2. CH3OH (1), [Ag(DPEphos)(dicnq)]BF4.CH3OH (2), [Ag(XANTphos) (dicnq)]CF3SO3 (3), {[Ag(XANTphos)(dicnq)]NO3}2 (4) and [Ag(XANTphos)(dicnq)]ClO4.CH2Cl2 (5) {DPEphos = bis[2-(diphenylphosphanyl) phenyl]ether, dicnq = 6,7-dicyanodipyridoquinoxaline, XANTphos = 9,9-dimethyl-4,5-bis(diphenylphosphanyl)xanthene} were characterized by X-ray diffraction, IR, 1H NMR, 31P NMR, fluorescence spectra and terahertz time-domain spectra (THz-TDS). In the five complexes the AgI, which is coordinated by two kinds of chelating ligands, adopts four-coordinate modes to generate mono-nuclear structures. The C-H...π interactions lead to formation of a 1D infinite chain for complexes 2 and 3. The crystal packing of complexes 1 and 5 reveal that they form 3D supermolecular network by several pairs of C-H...π interactions. The emissions of these complexes are attributed to ligands-centered [π-π8 ] transition based on both of the P-donor and N-donor ligands. [ABSTRACT FROM AUTHOR]

In this study, we synthesized series of La3Ga5SiO14:Pr3+ phosphors by high-temperature solid-state reactions. For the synthesized phosphors, X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive spectrum (EDS), Raman, infrared (IR), absorption, photoluminescence (PL) and photoluminescence excitation (PLE) characterizations and decay characteristics were performed. The XRD patterns indicate that the synthesized phosphors have the same D32 (P321) structure with La3Ga5SiO14 host. The SEM image and EDS pattern show the irregular morphology and the combined La, Ga, Si, O and Pr elements for the synthesized phosphors. The room temperature Raman and IR spectra show that the phonon modes of the La3Ga5SiO14:Pr3+ phosphors follow the overall mode distributions of La3Ga5SiO14 and no appreciable changes in the phonon properties are observed, indicating that the force fields in the La3Ga5SiO14:Pr3+ lattice are not strongly altered by Pr3+ doping. The UV-Vis absorption spectra show that the phosphors contain a strong absorption band and several moderate bands resulting from the 4f-5d and f-f transitions of Pr3+ ions, respectively. La3Ga5SiO14:Pr3+ phosphors produce white light when λex = 255 nm. On the basis of emission data, the concentration quenching mechanism of the Pr3+ emission was speculated as the dipole-dipole interaction. The decay time and thermal stability were investigated, and the CIE coordinates with the corresponding correlated color temperatures were also calculated. • Crystal analyses of LGS: Pr3+ phosphors. • Detail Raman characteristics of LGS: Pr3+ phosphors. • Generation of white light by LGS: Pr3+ phosphors upon the UV light excitation. • Unique temperature response characteristics of the LGS: Pr3+ phosphor. [ABSTRACT FROM AUTHOR]

The precise and real-time monitoring of localized pH changes is of great importance in many engineering and environmental fields, especially for monitoring small pH changes in biological environments and living cells. Metal–organic frameworks (MOFs) with their nanoscale processability show very promising applications in bioimaging and biomonitoring, but the fabrication of nanoscale MOFs is still a challenge. In this study, we synthesized a nanoscale mixed-lanthanide metal–organic framework by a microemulsion method. The morphology and size of the NMOF can be simply adjusted by the addition of different amounts of the CTAB surfactant. This NMOF exhibits significant pH-dependent luminescence emission, which can act as a self-referenced pH sensor based on two emissions of Tb3+ at 545 nm and Eu3+ at 618 nm in the pH range from 3.00 to 7.00. The MTT assay and optical microscopy assay demonstrate the low cytotoxicity and good biocompatibility of the nanosensor. [ABSTRACT FROM AUTHOR]

Five novel silver(I) complexes and two copper(I) phosphine complexes containing the bis[2-(diphenylphosphino)phenyl]ether ligand were synthesized and structurally characterized. Treatment of AgX / CuX and the bis[2-(diphenylphosphino)phenyl]ether with N^N ligands afforded the silver(I) or copper(I) complexes {[Ag 2 (POP) 2 (dpa)(H 2 O) 2 ](dpa)(ClO 4 ) 2 } n ( 1 ), {[Ag(POP)(dpp)](ClO 4 )} n ( 2 ), [Ag 2 (POP) 2 (4,4′-bipy)(CH 3 CN) 2 ](CF 3 SO 3 ) 2 ·CH 3 CN ( 3 ), {[Ag(POP)(dpe)](CF 3 SO 3 )·CH 3 CN} n ( 4 ), { [Ag 2 (POP) 2 (dpe)(H 2 O) 2 ](dpe)(BF 4 ) 2 } n ( 5 ), [Cu(POP)(bpy)](BF 4 ) ( 6 ) and [Cu 2 (POP) 2 (4,4′-bipy)](CF 3 SO 3 ) 2 ·4CH 3 CN ( 7 ) {POP = bis[2-(diphenylphosphino)phenyl]ether; dpp = 1,3-bis(4-pyridyl)propane; dpa = 1,2-bis(4-pyridyl)ethane; dpe = 1,2-bis(4-pyridyl)ethene; 4,4′-bipy = 4,4′-bipyridine; bpy = 2,2′-bipyridine}. These complexes are all characterized by IR, elemental analysis, X-ray diffraction, luminescence, 31 P NMR and 1 H NMR spectroscopy. Complex 5 has an irregular (6,3) network structure connected through hydrogen bonds between the C–H groups of aromatic rings and anions; complexes 1 and 2 are of 2D topological architectures which are linked by hydrogen bonds; complex 4 is of a 1D infinite zigzag chain structure formed by the bridging ligand dpe; complexes 3 and 7 are of dinuclear structures and complex 6 is of mononuclear structure. The choice of solvent and the type and coordination modes of the bipyridine derivatives are of importance in defining the structural and topological features of the resulting networks. In addition, the complexes 1 – 7 exhibit interesting luminescence in the solid state at room temperature. At the same time, we also studied the terahertz spectrum which provided some new informations of these complexes. [ABSTRACT FROM AUTHOR]

A water-stable metal-organic framework (MOF) EuNDC has been synthesized for selective detection of the well-known contaminant and toxicant picric acid (PA) in aqueous solution. Due to the photo-induced electron transfer and self-absorption mechanism, EuNDC displayed rapid, selective and sensitive detection of PA with a detection limit of 37.6 ppb. Recyclability experiments revealed that EuNDC retains its initial luminescent intensity and same quenching efficiency in each cycle, suggesting high photostability and reusability for long-term sensing applications. The excellent detection performance of EuNDC makes it a promising PA sensing material for practical applications. [ABSTRACT FROM AUTHOR]