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Improving the nighttime vision of drivers is essential, given the growing advancements in urban transportation. In this study, polyurethane-based self-luminous pavement coatings (PSCs) were prepared by doping luminous powders (LPs) into the polyurethane materials. The superior optical properties and chemical stabilities of these coatings were ensured by synthesizing the polyurethane-based material. Then, the PSCs were evaluated for their comprehensive performances, such as luminescence, aging resistance, and abrasion resistance, using various characterization methods, including fluorescence spectral analysis, Fourier-transform infrared spectroscopy, fluorescence microscopy, and mechanical property testing. The results show that the 50-mesh LP has the optimal overall performance, with an initial luminescence that exceeds those of the 100 and 400 meshes. The initial brightness of the PSC is mainly influenced by the LP and increases with dosage. The lattice structure and luminescent properties of the luminescent material did not change after coating preparation. The peak excitation wavelength of 420 nm implies that the coating has the best excitation effect under UV light. The primer-marking coating effectively improves the abrasion resistance of the PSC, and the mass loss of the PSC with a coating thickness of 0.4 kg/m² is 52.9% of that without the primer-marking coating, with the optimal coating thickness being 0.6 kg/m². This research provides an innovative solution to improve nighttime roadway lighting, which provides useful support for the sustainable development of urban transportation infrastructures and construction of intelligent transportation systems. [ABSTRACT FROM AUTHOR]

Two new cadmium(II) complexes [Cd0.5(HL)(bpa)0.5(H2O)]n·0.5nbpa and [Cd2(HL)2(L)(bpe)2]n·nH2L [H2L = 3-hydroxyisonicotinic acid, bpa = 1,2-bi(4-pyridyl)ethane, bpe = 1,2-bi(4-pyridyl)ethene] were synthesized by the reaction of a H2L and auxiliary N-containing ligands with Cd(II) ions under hydrothermal conditions. Obtained complexes were studied by elemental analysis, IR spectroscopy, powder XRD and X-ray crystallography. The thermal stability and luminescent properties of two complexes were investigated. [ABSTRACT FROM AUTHOR]

Extensive efforts have been devoted to magneto-optical (MO) glass, owing to its remarkable potential in modern optics, encompassing diverse applications such as optical isolation, modulation, and sensing. Although the Tb ions doped glass has good MO properties, high concentrations of Tb ions tend to cluster, resulting in glass crystallization. To further improve the performance of MO glass, we must improve the solubility of Tb ions and inhibit the oxidation of paramagnetic Tb3+ to diamagnetic Tb4+ by adjusting the glass composition. In this work, we conducted a comparative study on GeO 2 -B 2 O 3 -X 2 O 3 glasses doped with Tb 2 O 3 (TGBX, where X represents Ga or La) to elucidate the effects of Ga 2 O 3 and La 2 O 3 on glass properties. Our findings reveal that TGBG glasses exhibit superior MO performance compared to TGBL glasses. Notably, the Verdet constant of TGBG glass with 45 mol.% Tb 2 O 3 at 650 nm reaches 105 rad/(T·m). Although TGBL glass exhibits a lower Verdet constant, its higher glass network connectivity and higher concentration of Tb3+ ions suggest its potential for preparing larger-sized glasses with an increased Tb3+ molar ratio. [ABSTRACT FROM AUTHOR]

In this work, a novel white light emitting Dy3+ doped NaPbBi2(PO4)3 phosphors were synthesized for WLEDs application. The phase formation, morphological analysis and elemental composition of the prepared phosphors were investigated. The optical spectra revealed the nature of bonding (Dy3+ ions–ligand) and the band gap value of the optimized phosphor. The photometric analysis (PLE, PL spectra and lifetime value) at the room temperature and in the temperature range of 303–483 K were investigated. Exciting the phosphors at the near UV light gave rise to predominant emission in the blue and yellow region of the visible spectrum. The dipole–dipole interactions between the Dy3+ ions leads to concentration quenching effect which occured at 0.09 mol. The Judd–Ofelt intensity parameters were computed and the information about the radiative properties were attained through them. The emission of cool light (5474 K) with color purity 3.69%, lifetime time value of 0.631 ms and good thermal stability suggested that these phosphor is a potential candidate for WLEDs application. [ABSTRACT FROM AUTHOR]

Amidst growing concerns for environmental sustainability and green ecology, the utilization of Light Emitting Diodes (LEDs) for indoor plant cultivation has emerged as an influential area of research. Nonetheless, the growth of indoor plants is often constrained by inadequate lighting. Consequently, designing novel LEDs to create an appropriate light environment has emerged as a focal point in research. As a new type of photocatalytic material with excellent optical properties and light stability, double perovskite has broad application prospects in LEDs manufacturing. In this context, this article aims to synthesize a new Ca 2 Lu(Nb,Mn)O 6 double perovskite and study its optical properties in LEDs lighting for indoor plant growth. A new Ca 2 Lu(Nb,Mn)O 6 double perovskite were synthesized using the traditional high-temperature solid-phase method. The crystal structure and luminescence properties of the double perovskite were characterized in detail using powder X-ray diffraction (XRD), Rietveld refinement, excitation and emission spectra, decay lifetimes, quantum efficiency (QE), electron paramagnetic resonance (EPR) spectra, temperature-dependent emission spectra, and the Commission International de l'Eclairage (CIE) color coordinates. The photoelectric properties of Ca 2 Lu(Nb,Mn)O 6 and Ca 2 LuNbO 6 double perovskite have been explored through first-principles investigations. The absorption spectra from 270 to 600 nm indicates that it can be effectively excited by ultraviolet (UV) light. The emission spectra show a strong broad red emission peak at 684 nm. The luminescence mechanism has been studied using the Tanabe-Sugano diagram. In addition, the internal UV emission ratio β 1 , crystal field strength D q , and Racah parameters B and C were evaluated. The thermal stability of the sample was studied through emission spectra at heating temperatures from 303 to 573 K. The results indicate that Ca 2 Lu(Nb,Mn)O 6 double perovskite provides a new solution for indoor plant growth. [ABSTRACT FROM AUTHOR]

Rare earth Tb3+ doped gadolinium phosphate (GdPO4) green phosphor is a potential phosphor for white LED, while the preparation by conventional hydrothermal method has some problems, such as long reaction time and low doping amount of Tb3+. A series of Gd1 - x PO4 : xTb3+ (x = 0, 1%, 5%, 11%, 13%, 15%, 17%, 19%) samples were prepared by hydrothermal method combined with high temperature sintering. The phase structure, morphology, elemental composition, optical absorption and luminescence properties of samples were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM)-energy spectrometer (EDS), infrared spectrometer (FT-IR) and fluorescence spectrophotometer. The results show that, all the synthesized samples are pure phase of GdPO4 belonging to monoclinic monazite structure, and the Tb3+ are uniformly distributed in GdPO4 matrix and cause lattice shrinkage. Under 274 nm photoexcitation, GdPO4 :Tb3+ phosphors have the strongest emission peak at 545 nm, which belongs to 5D4→7F5 transition of Tb3+. The fluorescence quenching concentration of Tb3+ was determined to be 15% (molar ratio), and this sample (GdPO4 :15% Tb3+) exhibits excellent green light emission and good thermal stability. [ABSTRACT FROM AUTHOR]

A series of color tunable NaCa2-xMg2 (VO4)3 : xEu3+ (0≤x≤0. 10) phosphors were synthesized by molten salt method using cheap NaCl as molten salt. The effects of synthesis conditions and Eu3+ doping on the structure and luminescence properties of the samples were investigated in details. The results show that the optimum reaction conditions for the synthesis of NaCa2Mg2 (VO4)3 are reaction temperature of 800 °C, reaction time of 0. 5 h and mass ratio of raw material to molten salt of 1:3. The obtained samples are NaCa2Mg2 (VO4)3 pure phase with higher crystallinity. The micromorphology of the samples changed from coral-like to smooth irregular polyhedron with the increase of temperature. Eu3+ doping has little effect on the crystal structure of NaCa2 Mg2 ( VO4)3, but great effect on its luminescence properties. With the increase of Eu3+ concentration (x), the characteristic emission band intensity of VO43- gradually decreases, while the characteristic emission peak intensity of Eu3+ first increases and then decreases, reaching the maximum when x = 0. 06. Therefore, the luminous color of the samples can be modulated by changing the Eu3+ concentration, from green to yellow-green, yellow, yellow-white and orange-red. According to the fluorescence spectrum and fluorescence lifetime analysis, it is confirmed that the energy transfer process of VO43-to Eu3+ exists in NaCa2 Mg2 (VO4)3 : Eu3+ phosphors, and the energy transfer efficiency is about 23%. The thermal stability analysis shows that when the temperature increases from room temperature (298. 15 K) to 398. 15 K, the retaining ratio of the main emission peak intensity of NaCa2 Mg1. 94 (VO4)3:0. 06Eu3+ phosphor at 614 nm is 68. 4%, showing its good thermal stability. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Red phosphors play a key role in improving the optical quality of white light emitting diodes (WLEDs). In this work, Eu3+-activated red-emitting pyrophosphate phosphors of NaREP 2 O 7 :Eu3+ (RE = Sc, Lu) were prepared and the comparative investigations on crystal structures and luminescent properties were carried out. The X-ray diffraction (XRD), scanning electron microscope (SEM), and spectroscopy techniques were employed to characterize the materials. The features of crystal structures with regard to the Eu3+ doping were analyzed in detail on the basis of Rietveld crystal structure refinements. It is found that the Eu3+ tends to substitute Lu3+ in the NaLuP 2 O 7 :Eu3+, while in NaScP 2 O 7 :Eu3+ it tends to substitute Na+ due the principle of ionic size matching. The disparate selective occupation behaviour of Eu3+ ion in both crystals has resulted in a certain difference in fluorescence emission nature from each other. The doping concentration of Eu3+ was optimized for the strongest luminescence under near-ultraviolet (UV) excitation. The measurement of temperature-dependent luminescence showed that the emission of NaLuP 2 O 7 :Eu3+ at 150 °C maintained 77% of that at room temperature, and that for NaScP 2 O 7 :Eu3+ is 72%. Under the near-UV excitation, the fluorescence efficiency of the phosphors were assessed. The quantum efficiencies of NSPO:0.125Eu3+ and NLPO:0.125Eu3+ were measured to be 41.6% and 40.8%, respectively. The results imply that the Eu3+-activated pyrophosphate phosphors are promising red-emitting components in WLEDs. [ABSTRACT FROM AUTHOR]

For improving the night recognition of road markings and enhancing the driving safety of asphalt pavements, single-factor optimization is used to investigate the effects of the component materials, including luminescent power, pigment, filler, and anti-sedimentation agent, on the luminous performance of a coating. Additionally, their composition ratios are optimized using response surface methodology. A phosphorescent marking coating is prepared to investigate the micromorphology, excitation, and emission properties using scanning electron microscopy (SEM) and molecular fluorescence spectroscopy (MFS). The optimum thickness of the coating on an asphalt pavement is investigated, and the durability of the coating on asphalt pavement using a wheel rutting test is evaluated. The results show that the 300 mesh yellow-green luminous powder has the optimal overall performance, with an initial luminescence that exceeds that of orange and sky blue by three times. Initial brightness is mainly influenced by aluminate luminescent powder (ALP), which increases with the dosage. ALP and fumed silica powder (FSP) have a positive effect on brightness after centrifugation, and the effect of FSP dosage is more significant. ALP, rutile titanium dioxide powder (RTDP), and FSP influence the wear value of the coating, and the magnitude of the effect is RTDP > FSP > ALP. The optimal dosages of the main component are 27% ALP, 5% RTDP, and 0.8% FSP. The results of SEM show that the components in the coating are evenly dispersed, and the surface of the coating is rough. The peak excitation wavelength of 420 nm means that the coating has the best excitation effect in UV light, and its emission spectrum in the 440–760 nm wavelength range is well within the sensitive recognition zone of the human eye. The initial brightness gradually reached 4.38 cd/m2 when the coating thickness was increased from 482 μm to 546 μm, and the optimal application thickness of the luminous coating was determined to be 500 μm. At high and normal temperatures, the rutting stripping rates of the luminous marking coating are 16.8% and 8.2%, indicating its satisfactory durability. This study provides an experimental basis for the ratio optimization design of a luminous coating for asphalt pavements. [ABSTRACT FROM AUTHOR]

A series of Ca 2 GdNbO 6 : x Sm3+ (0.01 ≤ x ≤ 0.15) and Ca 2 GdNbO 6 : 0.03Sm3+, y Eu3+ (0.05 ≤ y ≤ 0.3) phosphors were synthesized by the traditional solid-state sintering process. XRD and the corresponding refinement results indicate that both Sm3+ and Eu3+ ions are doped successfully into the lattice of Ca 2 GdNbO 6. The micro-morphology shows that the elements of Ca 2 GdNbO 6 : 0.03Sm3+, 0.2Eu3+ phosphor are evenly distributed in the sample, and the particle size is about 2 μm. The optical properties and fluorescence lifetime of Ca 2 GdNbO 6 : 0.03Sm3+, Eu3+ phosphors were detailedly studied. The emission peak at 5D 0 →7F 2 (614 nm) is the strongest and emits red light under 406 nm excitation. The increase of Eu3+ concentration causes the energy transfers from Sm3+ to Eu3+ ions, and the transfer efficiency reaches 28.6%. Ca 2 GdNbO 6 : 0.03Sm3+, 0.2Eu3+ phosphor has a quantum yield of about 82.7%, and thermal quenching activation energy is of 0.312 eV. The color coordinate (0.646, 0.352) of Ca 2 GdNbO 6 : 0.03Sm3+, 0.2Eu3+ phosphors is located in the red area. The LED device fabricated based on the above phosphor emit bright white light, and CCT = 5400 K, Ra = 92.8. The results present that Ca 2 GdNbO 6 : 0.03Sm3+, Eu3+ phosphors potentially find use in the future. [ABSTRACT FROM AUTHOR]

Chromium-doped CaMgSi2O6 ( Cr 3 + : CMS) fluorescent ceramics with various concentrations were fabricated using solid-state reaction technique. All the samples were sintered at 1250 ∘ C for 3 h. Analysis of microstructure of the Cr 3 + : CMS ceramics shows homogeneous structure with grain size distributions between 0.86 nm and 2.26 nm. Luminescent spectra of the ceramics show two emission peaks, a strong peak at 872 nm and a weak peak at 960 nm because of 4 T 2 → 4 A 2 transition of the Cr 3 + ions. Intensity of the emission peaks increases with Cr 3 + concentration, reaches maximum with 0.1 at.% Cr 3 + , then decreases with higher Cr 3 + concentration. Owing to the differences in crystal field strength, the luminescent properties of the Cr 3 + : CMS fluorescent ceramics and powder are quite different. [ABSTRACT FROM AUTHOR]

A heteronuclear Tb-Al complex (1) was obtained by pyridine-2,6-dicarboxylic acid (H2PDA), AlCl3 and Tb4O7 under hydrothermal condition. Single-crystal X-ray diffraction analysis reveals that 1 is an ion-pair and consists of [Al(H2O)6]3+ cation and [Tb(PDA)3]3- anion; the [Al(H2O)6]3+ cations and [Tb(PDA)3]3- anions are further connected by hydrogen bonds to construct a 3D NaCl-like topology. Lattice water molecules in 1 fabricate a cubic (H2O)8-octamer by hydrogen bonds, which is located in the void of 1. Luminescent property indicates efficient energy transfer from PDA3- ligand to Tb3+ in 1, exhibiting the typical green emission of Tb3+ in the visible region. [ABSTRACT FROM AUTHOR]

Herein, four compounds containing the neutral viologen derivative, 1-(2-carboxyethyl)-4,4′-bipyridine (CBbpy) have been synthesized, (CBbpy)·(H 2 TPDC)·H 2 O (1), [Co 0.5 (CBbpy)(H 2 O) 2 ](HTPDC)·2 H 2 O (2), [Ni 0.5 (CBbpy)(H 2 O) 2 ](HTPDC)·2 H 2 O (3) and {[Cd(CBbpy) 2 (H 2 O) 2 ][Cd(TPDC) 2 ]·4 H 2 O} n (4) (H 2 TPDC = thiophene-2,5-dicarboxylic acid). Compound 1 is a co-crystal that forms the donor-acceptor (D-A) system through non-covalent interactions. Compounds 2 and 3 own the same isolated structure, in which metal ions coordinate with CBbpy to form cations, while H 2 TPDC loses a proton to form anions. Compound 4 contains one-dimensional (1D) {[Cd(CBbpy) 2 (H 2 O) 2 ]2+} n double chain and two-dimensional (2D) {[Cd(TPDC) 2 ]2-} n layer, which leads to a 1D + 2D→three-dimensional (3D) interdigitated supramolecular architecture. Although four compounds comprise the same bipyridinium moiety, their chromic behaviors are different. Compounds 1 and 4 own reversible photochromic action, while 2 and 3 reveal hydrochromic action upon heating. Based on the photochromic properties of 1 and 4 , the photo-modulated fluorescence and the potential applications of inkless and erasable printing are investigated. [Display omitted] • Four compounds have been successfully prepared by utilizing the 1-(2-carboxyethyl)-4,4′-bipyridine (CBbpy) viologen ligand. • Compounds 1 and 4 own reversible photochromic action, while 2 and 3 reveal hydrochromic action upon heating. • The photo-modulated fluorescence and the inkless erasable printing capability are investigated. [ABSTRACT FROM AUTHOR]

• Two novel photochromic Zn-MOFs have been successfully prepared. • Compound 1 is layered, while 2 displays unique Anderson-like metal-carboxylate cluster that forms 3D structure. • The photo-modulated fluorescence and the inkless erasable printing capability are investigated. By using the flexible viologen carboxylate ligand 1,1′-bis(4-carboxybenzyl)-4,4′-bipyridinium dichloride (H 2 BpybcCl 2) and two kinds of aromatic dicarboxylic acids (1,4-benzenedicarboxylic acid = p -H 2 BDC, 1,2-benzenedicarboxylic acid = σ -H 2 BDC), two novel Zn-MOFs {[Zn 4 (Bpybc) 6 (H 2 O) 12 ]·(p -BDC) 3 ·(OH) 2 ·22H 2 O} n (1) and {KZn 6 (Bpybc) 3 (σ -BDC) 6 ·OH} n (2) have been successfully synthesized. Complex 1 represents the two-dimensional (2D) layered network, while complex 2 displays the unique Anderson-type metal-carboxylate cluster that forms a three-dimensional (3D) framework. It is noticeable that the shape of dicarboxylic acids can have a direct effect on the pattern of the interpenetrated frameworks. In addition, compounds 1 and 2 demonstrate photochromism via reversible electron transfer (ET) and undergo an obvious color transformation owing to the generation of viologen free radicals. Furthermore, we investigated the fluorescent properties under photo modulation and their potential applications in ink-less and erasable printing. Two novel photochromic Zn-MOFs have been successfully synthesized. Compound 1 is layered, while 2 displays unique Anderson-like metal-carboxylate cluster that forms 3D structure. [Display omitted] [ABSTRACT FROM AUTHOR]

• Three compounds containing 1-carboxyethyl-4,4′-bipyridine have been synthesized. • Compounds 1 and 3 exhibit photochromism, while 2 reveals hydrochromism upon heating. • Photo-controlled fluorescence and ink-free erasable printing abilities are discussed. Herein, three compounds containing the neutral viologen derivative, 1-carboxyethyl-4,4′-bipyridine (CEbpy) have been synthesized, (CEbpy)·(H 2 TPDC)·2H 2 O (1) [Co(CEbpy)(TPDC)(H 2 O) 4 ]·3H 2 O (2) and [Cd 3 (CEbpy) 2 (TPDC) 3 ·7H 2 O] n (3) (H 2 TPDC = thiophene-2,5-dicarboxylic acid). Compound 1 is a supramolecular assembly, linked by non-covalent interactions to constitute the donor-acceptor (D-A) system. Compound 2 owns a zero-dimensional (0D) isolated structure in which metal ions are coordinated with CEbpy and fully deprotonated (TPDC)2- ligands. Compound 3 exhibits a three-dimensional (3D) framework of trinuclear metal clusters, where each metal atom forms its own distinct linear one-dimensional (1D) chain along a specific axis. Although the three compounds comprise the same bipyridinium moiety and aromatic acid, their chromic behaviors are different. Compounds 1 and 3 exhibit reversible photochromism, while 2 reveals hydrochromism upon heating. Additionally, photo-modulated fluorescence as well as their potential applications in inkless erasable printing have been studied. [Display omitted] [ABSTRACT FROM AUTHOR]

Two new Zn(II) metal-organic frameworks (MOFs) {[Zn(Bpybc) 0.5 (m -BDC)(H 2 O)]·2H 2 O} n (1) and {[Zn(H 2 Bpybc)(BTEC)(H 2 O) 2 ]·H 2 O} n (2) have been successfully synthesized, where 1,1′-bis(4-carboxybenzyl)-4,4′-bipyridinium dichloride (H 2 BpybcCl 2) is used to react as the predesigned ligand with two kinds of aromatic carboxylic acids (1,3-benzenedicarboxylic acid = m -H 2 BDC, 1,2,4,5-benzenetetracarboxylic acid = H 4 BTEC) as the secondary building linkers. Both two compounds own two-dimensional (2D) layered structures. In addition, compounds 1 and 2 display reversible photochromism, which is associated with the generation of free radicals via photoinduced electron transfer. Simultaneously, the photomodulated fluorescent properties and their potential applications in ink-less and erasable printing were also studied. Two novel Zn(II)-based photo-responsive 2D-MOFs, {[Zn(Bpybc) 0.5 (m -BDC)(H 2 O)]·2H 2 O} n (1) and {[Zn(H 2 Bpybc)(BTEC)(H 2 O) 2 ]·H 2 O} n (2), derived from 1,1′-bis (4-carboxybenzyl)-4,4′-bipyridine dichloride (H 2 BpybcCl 2) and two aromatic carboxylic acid ligands (m -H 2 BDC = 1,3-benzenedicarboxylic acid, H 4 BTEC = 1,2,4,5-benzenetetracarboxylic acid) as the secondary building linkers, have been synthesized and characterized. Two compounds both display unique 2D networks and exhibit reversible photochromic behavior due to the generation of free radicals via photo-induced electron transfer (PET). [Display omitted] • Two novel Zn(II)viologen-based 2D-MOFs have been prepared. • Compounds 1 and 2 exhibit reversible photochromic behavior due to PET. • The photo-modulated fluorescence and the inkless erasable printing capability are investigated. [ABSTRACT FROM AUTHOR]

Oxide matrix red-emitting phosphors are deemed as excellent color converters for white light emitting diodes (WLEDs) and laser diodes (LDs). Manganese-doped MgAl2O4 powder was synthesized by a solid-state reaction method at different sintering temperatures. Microstructure shows that grain size is mainly in the range of 0.2–5 μm, and grain agglomeration occurs with increased sintering temperature. XPS analysis indicates that the doped Mn ion exhibits a valence state of + 4 within the MgAl2O4 matrix. The diffraction peak of the phosphors is shifted by the sintering temperature, which affects lattice constant. Upon excitation by 300 nm ultraviolet light, the samples emit asymmetric broadband red light within the range of 620–720 nm, attributed to Mn4+ ion’s transition from 2Eg to 4A2g states. With the increasing temperature, the main emission peak shifts from 677 nm to 650 nm, ascribed to the change in energy level (2Eg) resulting from the reduction of Al2O3 phase. Crystal field theory confirmed that Mn4+ ions are within a strong crystal field environment created by MgAl2O4 matrix. By affecting particle size and crystallinity, the sintering temperature influences the fluorescence lifetime of the Mn4+ ion. Notably, these red-emitting phosphors exhibits remarkable thermal stability as their emission intensity remains approximately at 58% of initial intensity even at elevated temperature (435 K). Consequently, Mn4+: MgAl2O4 red-emitting phosphors with high thermal stability render them promising candidates for WLED applications. [ABSTRACT FROM AUTHOR]

• Three new 2D coordination polymers have been got by utilizing the carboxybenzyl viologen ligand. • Compounds 1 and 2 exhibit electron transfer photochromism, while compound 3 displays hydrochromism through dehydration. • The photo-modulated fluorescence and the inkless erasable printing capability are investigated. By utilizing the carboxybenzyl viologen ligand 1-(3-carboxybenzyl)-4,4′-bipyridinium chloride (HBcbpy·Cl), 1,3,5-benzenetricarboxylic acid (H 3 BTC) and varying different metal ions, three new coordination polymers [Cd(Bcbpy)(HBTC)(H 2 O)·2H 2 O] n (1), [Zn(Bcbpy)(HBTC)(H 2 O)·2H 2 O] n (2) and [Co 2 (Bcbpy) 2 (HBTC) 2 (H 2 O) 2 ·4H 2 O] n (3) have been synthesized and structurally characterized. Compounds 1 and 2 have identical two-dimensional (2D) coordination layered structure, while compound 3 features 2D+2D→2D structure. It is interesting that compounds 1 and 2 exhibit electron transfer photochromism, while compound 3 displays hydrochromism through dehydration. At the same time, considering the high stability and fast photo-response, the photo-modulated fluorescence and the inkless erasable printing capability are investigated. Three CPs derived from 1,3,5-benzenetricarboxylic acid (H 3 BTC)and a neutral viologen ligand 1-(3-carboxybenzyl)-4,4′-bipyridinium (Bcbpy) with different metal ions have been prepared and characterized. Compounds 1 and 2 possess 2D layered structure and exhibit photochromic properties due to the generation of free radicals, while compound 3 owns 2D+2D→2D structure and displays hydrochromism through dehydration and rehydration. [Display omitted] [ABSTRACT FROM AUTHOR]

A new 3D organic-inorganic hybrid solid [Cu4 (SCN)4 (bpp)2]n (1) was obtained via the self-assembly of inorganic ladder-like chains [Cu(SCN)]n with the flexible organic ligands 1,3-di(4-pyridyl) propane (bpp) under solvothermal conditions. It is noted that the bpp ligands show two kinds of conformations (trans-gauche or trans-trans) in the asymmetric unit, which linked by similar staircase-like [Cu(SCN)]n chains to form crystallographically distinct [Cu2 (SCN)2 (bpp)]n layers A and B. Furthermore, two different layers are packed in an offset ABB′A′ pattern to generate unique 3D structure. Compound 1 was further characterized by infrared spectroscopy (FT-IR), powder diffraction (PXRD), thermal analysis, solid state diffuse reflectance spectroscopy (UV-Vis) and photoluminescent studies. The solid UV-Vis diffuse-reflectance spectroscopy shows strong absorption spectra in ultraviolet region, and a wide-gap semiconductor with band gap of 3.20 eV. Compound 1 shows different photocatalytic activities for neutral red (NR), methyl orange (MO), azure I (AI), methylene blue (MB) and brilliant blue (ED) degradation under UV-light irradiation, which could be related to the slight charge and size difference of organic dyes. Compound 1 shows strong green photoluminescence at room temperatures with emission peaks at about 525 nm, which may be associated with a ligand-centered excited state with a possible involvement of metal-to-ligand or ligand-to-ligand charge transfer. [ABSTRACT FROM AUTHOR]

Two new Zn(II)/Co(II) coordination polymers, [Zn1.5(pmda)(OH)(bipy)]2n·2nH2O (1) and [Co(pmda)(bib)]n(2) (H2pmda = 4,4′-[1,2-phenylenebis(methyleneoxy)]dibenzoic acid, bipy = 4,4′-bipyridine, bib = 1,4-bis(imidazol-1-yl)-butane), have been prepared under hydrothermal conditions. Their structure were determined by single-crystal X-ray diffraction analysis, and further characterized by elemental analysis, IR spectra TG, and powder X-ray diffraction analysis. Complexes 1 and 2 both exhibit two-dimensional network structures and the intermolecular hydrogen bonding, π-π stacking interactions extend them into 3D supramolecular architectures, which play an important role in stabilizing them. The solid-state luminescent property of 1 and 2 were characterized and the results revealed that they exhibit fascinating photoluminescence properties. In addition, the sensing property of only 1 has been examined briefly. The quantum-chemical calculations of complex 1 have been performed on 'molecular fragments' extracted from the crystal structure using the PBE0/LANL2DZ method built in Gaussian 16 Program. [ABSTRACT FROM AUTHOR]

β-Ga2O3∶Eu3+ samples with different fluence were prepared by ion implantation method and then annealed in air where Eu3+ optical activation was successfully achieved. The stress variation trend of β-Ga2O3 single crystals with Eu3+ fluence was characterized by Raman spectra and X-ray diffraction. It was found that with the increase of Eu3+ fluence, the crystal lattice stress increases first and then decreases, and its internal mechanism was analyzed. The luminescence properties of Eu3+ were characterized by cathodoluminescence spectra. The wide defect luminescence peak near 380 nm and the characteristic luminescence peaks of Eu3+ near 591 nm, 597 nm and 613 nm were observed. By Gaussian fitting, the 380 nm luminescence peak could be divided into three peaks located at about 360 nm, 398 nm and 442 nm, which are related to the self-trapping excitons and donor-acceptor pairs, respectively. In addition, the position and intensity of Eu3+ luminescence peaks were affected by the localized crystal field of the host. [ABSTRACT FROM AUTHOR]

A series of self-assembled 3D flower-like NaY1-x (WO4)2:xSm3+ (x = 0, 0. 005, 0. 010, 0. 015, 0. 020, 0. 025, 0. 030) powders were prepared by hydrothermal method and high temperature sintering, with trisodium citrate as the anchoring agent. The phase structure, morphology, composition and luminescence properties were characterized by X-ray powder diffraction(XRD), scanning electron microscopy(SEM), infrared spectrum(FT-IR) and photoluminescence spectroscopy (PL), respectively. The results show that the synthesized samples are pure NaY(WO4)2 with tetragoonal scheelite structure. NaY(WO4)2:Sm3+ powders can be excited by a wavelength of 405 nm and exhibit a strong orange-red emission at 600 nm, corresponding to the 4G5/2 →6H7/2 magnetic dipole transition of Sm3+. The optimum doping molar fraction of Sm3+ is determined to be of 0. 015 based on the maximum intensity of fluorescence emission. [ABSTRACT FROM AUTHOR]

GdVO4 : Eu3+ nanophosphors co‐doped with alkali metal ions (Li+, Na+, K+) of various concentrations were fabricated by an efficient hydrothermal method. The microstructure and luminescent emission properties were tested systematically. The results demonstrated that the co‐doping of M+ led to lattice distortion, which is closely related to dopants' ionic radii and concentrations. The lattice distortion further resulted in a fluctuation of luminescent brightness. The optimal luminescent properties of GdVO4 : Eu3+ co‐doped with Li+(10 atom‐% (at. %)), Na+(8 at. %), K+(6 at. %) were achieved respectively. Among them, the GdVO4 : Eu3+ co‐doped with Li+ of 10 at % possessed the highest emission intensity. Moreover, the alkali metal ions co‐doping also gave rise to the elevation of the concentration quenching threshold of Eu3+, which further enhanced the luminescent performance. [ABSTRACT FROM AUTHOR]

In order to study the effect of Na+ doping on the luminescence of Ca2GdNbO6: 0.03Sm3+ phosphors, a series of Ca2GdNbO6: 0.03Sm3+, xNa+ (x = 0.01, 0.03, 0.05, 0.07, 0.10; x is mole fraction) phosphors were successfully synthesized by high-temperature solid-state reaction.XRD patterns and the corresponding refinement results show that Na+ were successfully doped into Ca2GdNbO6: 0.03Sm3+ lattices. The luminescent properties of Ca2GdNbO6: 0.03Sm3+, xNa+ phosphors illustrate that the introduction of Na+ effectively improves the luminous intensity of Ca2GdNbO6: 0.03Sm3+ phosphors. Under the 406 nm excitation, the optimum doped concentration of Na+ is 5%, as well as the phosphors emit orange-red light with the strongest emission peak at 602 nm (4 G5/2 →6 H7/2). The calculation of the concentration quenching and the thermal stability of Ca2GdNbO6: 0.03Sm3+, 0.05 Na+ host show that the energy transfer in the matrix occurs mainly among the nearest neighbor ions, and the thermal activation energy is 0.119 eV. The calculated color coordinate (0.593 5, 0.404 7) of the phosphors is located in the orange-red region, which is close to the standard (0.666, 0.333) specified by the international commission on illumination, indicating Ca2GdNbO6: 0.03Sm3+, xNa+ phosphors have potential application prospects in the field of white LEDs. [ABSTRACT FROM AUTHOR]

Two coordination complexes, namely [Zn2(4-APha)2(CH3COO)2(H2O)2] (1) and [Cd(4-APha)(CH3COO) (H2O)0.5]4·6H2O (2) (4-APha = 4-aminophenylhydroxamic acid), are synthesized by the solvothermal method. They are characterized by single crystal X-ray diffraction, IR, TGA, and elemental analysis. Structural analyses reveal that both complexes 1 and 2 belong to the monoclinic system, space group C2/c. The difference is that complex 1 shows a binuclear structure and complex 2 displays a 3D structure. It is noteworthy that complex 1 exhibits an excellent thermal stability and no weight loss below 117 °C. Meanwhile, the luminescent properties of complexes 1 and 2 in the solid state are also investigated at room temperature. [ABSTRACT FROM AUTHOR]

A serious of lutetium stabilized gadolinium aluminum garnet transparent ceramics {(Gd, Lu)3 Al5 O12 ∶Tb, Eu} were prepared by co-precipitation method combining vacuum sintering process. Then the transparent ceramics with the thickness of 1 mm were polished. Crystal structure of transparent ceramic samples was characterized by X-ray diffraction and the optical property was characterized by fluorescence spectrophotometer and UV near infrared spectrophotometer. After the process of sintering ceramics at high temperature, the ceramic samples still maintain stable garnet phase. In the emission spectra obtained by UV excitation of different samples. 313 nm was selected as the excitation wavelength of transparent ceramics and the strongest emission peak can be obtained. The emission light from green light to red light can be adjusted. After 313 nm excitation, all transparent ceramic samples have a millisecond decay time of Eu3+ at 543 nm and 591 nm emission wavelengths. [ABSTRACT FROM AUTHOR]

Gd2O3:Tb3+ nanocrystal co-doped with Zn2+ and Li+ was prepared by the combination of polyol and solid-phase methods. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), photoluminescence (PL) spectra and magnetic resonance imaging (MRI). The results revealed that both Gd2O3:Tb3+/Zn2+ and Gd2O3:Tb3+/Li+ had cubic unit structures with a spherical shape, and the fluorescence intensity of the nanoparticles reached a maximum at a doping concentration of 0.050 mmol% for Zn2+ and 2 mol% for Li+, respectively. In addition, the T1/T2 (longitudinal/transverse relaxation time)-weighted MRI signals got enhanced due to the increased longitudinal relaxivity (r1) and transverse relaxivity (r2) after the doping by metal ions. Therefore, the materials reported here can be used for fluorescence and MR bimodal imaging, as tracers and for fluorescence detections. [ABSTRACT FROM AUTHOR]

A new Eu(III) compound, namely [Eu(L)(H2O)]n (1 H3L = biphenyl-3,4',5-tricarboxylic acid), has been hydrothermally synthesized and structurally characterized. Single-crystal X-ray diffraction analysis indicated that Compound 1 crystallizes in the tetragonal chiral space group I41 and displays a twofold interpenetrated 3D framework containing 1D right-handed 41 helical chains as building subunits. Moreover, Compound 1 has intense Eu(III) characteristic emission with the quantum yield of 68.2%. [ABSTRACT FROM AUTHOR]

The photosensitivity of the compounds should be due to the rational modulation of electron acceptors and donors. [Display omitted] Two novel Mn(II)-based one-dimensional coordination polymers {[Mn(bcbpy)(H 2 O) 4 ]·(p -BDC)·2H 2 O} n (1) and {(bcbpy)·[Mn(NDC)(H 2 O) 4 ]·DMF·3H 2 O} n (2) constructed from the viologen moiety (1,1′-bis(3-carboxylatobenzyl)-4,4′-bipyridinium = bcbpy) and different aromatic dicarboxylic acids (p -phthalic acid = p -H 2 BDC, 1,4-naphthalene dicarboxylic acid = H 2 NDC), have been synthesized by solvent evaporation and characterized systematically. Their crystal structures and photochromic behaviors are investigated. Both complexes exhibit reversible photochromism due to forming viologen radicals through electron transfer. Meanwhile, photo-controlled fluorescence and ink-free erasable printing capabilities are discussed to enrich the research on crystal photophysical properties. [ABSTRACT FROM AUTHOR]

The CIE 1931 Chromaticity diagram for the NPbBP: xSm3+ phosphors at the room temperature and for the NPbBP: 0.03Sm3+ phosphors in the temperature range (303 K- 483K) [Display omitted] • The novel orthophosphate NaPbBi (2-x) (PO 4) 3 : xSm3+ phosphors were synthesized via conventional solid state reaction method. • The crystal structure and luminescent properties of NaPbBi (2-x) (PO 4) 3 : xSm3+ were systematically investigated. • The reddish-orange light emitting phosphor with high color purity (99.4 %) was obtained. The red phosphor for light application is in high demand. In this regard, a series of orange-red phosphors, NaPbBi 2 (PO 4) 3 : Sm3+, with a single phase were obtained by the conventional solid state reaction method. The X-ray diffraction (XRD) confirms that the phosphor belongs to the cubic structure with a space group I-43d (220). The optical property of the phosphor was studied through the diffuse reflectance spectroscopy measurements and the characteristic peaks of the Sm3+ ions were identified. Exciting the phosphors at 404 nm, produced a strong orange-red emission at 601 nm. The optimum concentration of the phosphor was found to be 0.03 mol. In all emission transitions of the Sm3+ ions within the host lattice, the energy transfer (ET) occurs among the nearest neighbour ions. The lifetime values were in the order of milliseconds. The photometric parameters revealed that the emission lies in the orange-red region with color coordinates (0.5863, 0.4129) and a color purity of 99.4 %. The temperature dependent luminescence properties of the phosphor were also investigated and all these results showed that the phosphor could serve as a good candidate for light/light sensing applications. [ABSTRACT FROM AUTHOR]

• Tb-MOF and Sm-MOF based on H 3 ttc were obtained and characterized. • Tb-MOF and Sm-MOF are isomorphic and show a 3D network structure based on terbium/samarium unit. • Tb-MOF can be used as a multifunctional fluorescent probe with high selectivity and excellent sensitivity to detect TNP, Cr 2 O 7 2- and Al3+. • Tb-MOF will be a promising candidate and applies to the field of fluorescent ink and fingerprint retrieval. Two three-dimensional metal organic framework {[L n 2 (ttc) 3 ]∙1.5 DMF} n {Ln3+=Tb3+(1), Sm3+(2)} was synthesized by solvothermal reaction of rare earth metal Ln3+ ions and 1-imidazol-1-yl-2,4,6-benzene-tricarboxylic acid (H 3 ttc). The crystal characteristics and composition of the two compounds were confirmed by powder X-ray diffraction (PXRD) and thermogravimetric analysis (TG), and the single crystal X-ray diffraction confirmed that they are isomorphic. The luminescence and sensing properties of the two compounds were investigated in detail, the Tb-MOF exhibits characteristic emission of Tb3+ through effective sensitization by antenna effect and emits bright green fluorescence under excitation light of 254 nm. Fluorescence experiments show that Tb-MOF has high selectivity and sensitivity for the detection of TNP, Cr 2 O 7 2−, and Al3+ with the limit of detection of 2.89×10−8 mol·L−1, 2.35×10−8 mol·L−1 and 2.69×10−8 mol·L−1, respectively. In addition, possible luminescence quenching mechanisms are discussed. As a result, such a Tb-MOF will be a promising candidate and applies to the field of fluorescent ink and fingerprint retrieval. Two three-dimensional metal organic framework {[L n 2 (ttc) 3 ]∙1.5 DMF} n {Ln3+=Tb3+(1),Sm3+(2)} was synthesized by solvothermal reaction of rare earth metal Ln3+ ions and 1-imidazol-1-yl-2,4,6-benzene-tricarboxylic acid (H 3 ttc). The crystal characteristics and composition of the two compounds were confirmed by powder X-ray diffraction (PXRD) and thermogravimetric analysis (TG), and the single crystal X-ray diffraction confirmed that they are isomorphic. The luminescence and sensing properties show that Tb-MOF hashigh selectivityand sensitivity for the detection of TNP, Cr 2 O 7 2−, and Al3+ with low detection limit. In addition, possible luminescence quenching mechanisms are discussed. Asa result, such a Tb-MOF will be a promising candidate and applies to the field of fluorescent ink and fingerprint retrieval. [Display omitted] [ABSTRACT FROM AUTHOR]

The pyrophosphate NaLaP 2 O 7 (NLP) samples doped with Tb3+ and Eu3+ were prepared by a simple high-temperature solid state reaction method. The XRD, SEM and spectroscopy were used for characterization. The phosphors exhibited a pure phase identified by XRD. The powders are aggregates of much smaller particles with individual sizes of about 1 μm or even smaller in diameter. The crystal structures were refined by the Rietveld method, and the unit cell parameters decreased with increasing doping concentration. The luminescence properties of the phosphors are analyzed in detail. The optimal doping concentration was determined to be 16 at.% for NLP:Tb3+ and 10 at.% for NLP:Eu3+. The color tunable luminescence from green to red was achieved by co-doping Tb3+ and Eu3+. The fluorescence dynamics fitting based on the Inokuti-Hirayama model revealed that the energy transfer mechanism is mainly contributed by the electronic dipole-dipole interaction. The energy transfer efficiency from Tb3+ to Eu3+ under 376 nm excitation is more than 50 % when the concentration of Eu3+ exceeds 10 %. Under 376 nm excitation, the emission intensity of NLP:0.16 Tb3+, 0.10Eu3+ at 423 K remains 86 % of that at room temperature, and the quantum efficiency of NLP:0.16 Tb3+, 0.10Eu3+ at room temperature is 44.29 %. The results indicate that the prepared NLP:Tb3+, Eu3+ is potential for pc-WLED applications. • The pyrophosphate NaLaP 2 O 7 doped with Tb3+/Eu3+ is developed for multicolor luminescence. • The luminescence color can be tuned from green to red. • The energy transfer mechanism is analyzed based on the Inokuti-Hirayama model. • The luminescence exhibits very good quantum efficiency and thermal stability. [ABSTRACT FROM AUTHOR]

The binuclear double helix copper (I) complex was synthesized and structurally characterized. The oxidation state of copper is confirmed by BVS calculation, UV–Vis spectra and photo-luminescence analysis. Importantly, Cu(I) complex behave as good catalyst for the catalytic carboxylative cyclization reaction of propargylic amines with carbon dioxide towards oxazolidinones synthesis with high TON and that have been studied by the compounds using Gas Chromatographic (GC) conversion. Again, the plausible catalytic reaction mechanism is framed from DFT calculations. [Display omitted] • Double helix Copper (I) dimeric complex. • X-ray crystal analysis. • Catalytic fixation of carbon dioxide. • Oxazolidinones products from Propargylamines. • DFT studies for framing mechanism. The application of economically abundant, renewable and C1-feedstock, carbon dioxide into organically important compounds is considered as the hot topic in modern aspects. In this prospective, a binuclear double helix copper (I) complex (1) was synthesized through insitu reaction between quinolone-2-carbaldehyde and succino-hydrazide with copper (II) nitrate hexahydrate. Single crystal X-ray analysis of complex 1, clearly explained that both tetra co-ordinated Cu(I) ions are in tetrahedral geometric environment, having suprmolecular network arrangement via weak interaction of H-bonding, π...π stacking and C H...π stacking. The complex 1 was found to be effectively active catalyst in carboxylative cyclization reaction of propargylic amines with carbon dioxide towards oxazolidinones synthesis under atmospheric pressure and mild reaction conditions. Due to the initiation of side reaction by –NH 2 group of primary propargyliamines, which reduces the yield percentage of respective oxazolidinones as a result the carboxylative cyclization reaction of primary propargylic amines, was rarely developed. In this work both primary and secondary propargylamines smoothly undergoes through this catalytic reaction and produced high percentage of desired oxazolidinones product. Again neat condition for this catalytic reaction makes the methodology more environmentally benign and sustainable. The complex 1 showed luminescent property. Moreover DFT methods were utilized in order to explain the probable mechanistic pathway of carboxylative cyclization reaction. [ABSTRACT FROM AUTHOR]

Treatment of Ni(OAc)2·4 H2O with 3,4-pyrazoledicarboxylic acid (H3pdc) and imidazole (ImH) in different metal-to-ligand ratios afforded two dinuclear nickel(II) complexes, [Ni(Hpdc)(ImH)(H2O)2]2·4 H2O (1) and [Ni(Hpdc)(ImH)2(H2O)]2·2.5 H2O (2), which were characterized by elemental analysis (EA), IR spectra and X-ray diffraction analysis and thermogravimetric analysis (TGA). Both in 1 and 2, the dinickle unit [Ni2(µ2-Hdpc)2] with six-numbered Ni2N4 ring was formed by a pair of µ2-Hpdc2− ligands linked two Ni(II) ions in N,O-chelating and N‒N-bridging fashions. The dinuclear units in 1 and 2 were expanded to 2D layer structures though hydrogen-bonding interactions between coordination water molecules, ImH molecules and carboxylate oxygen atoms, whereas the lattice water molecules in 1 and 2 just embedded in the 2D layer through intermolecular hydrogen bonding interactions. Finally, the 2D sheets in 1 were further assembled to a 3D supramolecular architecture via intermolecular C–H⋯O hydrogen bond. Besides, the luminescent and electrochemical properties of two complexes have been reported. Two dinuclear nickel(II) complexes, [Ni(Hpdc)(ImH)(H2O)2]2·4 H2O (1) and [Ni(Hpdc)(ImH)2(H2O)]2·2.5 H2O (2), were obtained by assembling of a Ni(II) ion, 3,4-pyrazoledicarboxylic acid (H3pdc) and imidazole (ImH) in different metal-to-ligand ratios. In 1 and 2, the O(C, N)−H⋯O hydrogen bonds expanded the dinuclear complexes to 3D/2D supramolecular structures, respectively. [ABSTRACT FROM AUTHOR]

Cadmium complexes are widely used in the fields of optics, medicine, chemistry and so on because of their unique structure and properties. Hydrothermal method is one of the most convenient and effective methods to synthesize complex at present because of its solvent cleaning and simple operation. A compound [ Cd2 ( L)2 ( bdc) ( H2 O)4 ] ( bdc) was hydrothermally synthesized using 2,6-di(pyrazin-2-yl)-4,4′-bipyridine(L), terephthalic acid and CdCl2 ·2. 5H2 O as raw materials, the structure and luminescent properties of the complexes were characterized by single crystal X-ray diffraction and infrared spectroscopy. The experimental results show that the [Cd2 (L)2 (bdc) (H2 O)4] (bdc) belongs to the triclinic system, P1 space group, a =1. 002 78(17) nm, b = 1. 044 25(17) nm, c = 1. 274 8(2) nm, β = 78. 559(2)°, and has good fluorescence. [ABSTRACT FROM AUTHOR]

In the present work, the synthesis of the target products using sodium metasulfite (Na2S2O5) and p-toluenesulfonic acid (PTSA) separately as catalysts was studied. Herein, the liquid phase microwave method was chosen to synthesize triphenylamine substituted mono- and di-branched benzimidazole derivatives compared with the solid phase microwave method, and the reaction conditions were optimized using Na2S2O5 as a catalyst in N,N-dimethylformamide (DMF) solvent. A possible reaction mechanism is discussed. Ten new triphenylamine-benzimidazole derivatives were successfully synthesized. On this basis, PTSA using a catalyst was introduced into the reaction, the yields of the target products were evidently increased (the yield was enhanced 5‒22% using PTSA as a catalyst). It is found that PTSA only acted as a catalyst, while Na2S2O5 acted as both a catalyst and an oxidant, and PTSA could effectively catalyze the synthesis of benzimidazoles. Further, the luminescent properties of the synthesized compounds were comparatively studied after the structures of the synthesized compounds were confirmed. The results showed that the fluorescence quantum yield and the intensity of the synthesized compounds were enhanced with the increase in the number of substituted benzimidazole on triphenylamine, and the different substituents on 5-position of benzimidazole also have significant effect on the luminescent properties of the compound. [ABSTRACT FROM AUTHOR]

A new 3D Cd(II) metal–organic framework of [Cd2(HIDC)2(bibp)1.5]n (1) was synthesized hydrothermally by the reaction of imidazole-4,5-dicarboxylic acid (H2IDC) and 4,4′-bis(imidazol-1-ylmethyl)biphenyl (bibp) with Cd(NO3)2·4H2O. Single-crystal X-ray diffraction analysis reveals that this compound crystallizes in triclinic, space group Pī with a = 9.6610(3), b = 15.5866(5), c = 16.0228(6) Ǻ, α = 110.662(3), β = 101.521(3), γ = 107.115(3)˚, V = 2029.46(15) Ǻ3, Z = 2, Dc = 1.644 g cm−3, µ = 1.113 mm−1, F(000) = 1002, the final R1 = 0.0468 and wR2 = 0.0962 for 8932 observed reflections with I > 2σ(I). In 1, the alternately interconnection of Cd(II) ions by µ2-HIDC2− and µ3-HIDC2− anions resulted in the formation of 1D [Cd2(µ2-HIDC)(µ3-HIDC)]∞ with the right- and left-helical chains, which were further linked by the oxygen atoms derived from one of the carboxylate groups of µ3-HIDC2− anions, generating the 1D double helical chain structure of [Cd4(µ2-HIDC)2(µ3-HIDC)2]∞ along a axis. These adjacent 1D double chains are further linked by cis-µ2-bibp ligands to form a 2D network structure of [Cd4(µ2-HIDC)2(µ3-HIDC)2(cis-µ2-bibp)2]n, which are further pillared by trans-µ2-bibp ligands to generate a 3D layered-pillared metal–organic framework architecture of [Cd4(µ2-HIDC)2(µ3-HIDC)2(cis-µ2-bibp)2(trans-µ2-bibp)]n. Furthermore, the thermal stability and luminescent property of 1 have also been investigated. A 3D Cd(II) layered-pillared metal–organic framework was synthesized hydrothermally. This new compound displays high thermal stability and intense fluorescent emission. [ABSTRACT FROM AUTHOR]

Three new transition metal complexes, [Zn(L1)2(OTs)(CH3OH)](TsO)·CH3OH (1), {[Zn(L2)(H2O)4](SiF6)·H2O}n (2) and {[Cd(L2)2(OTs)2]·2DMF}n (3), were prepared from pyridine thiazolone derivatives (where L1 = 2-[4-(2-pyridinyl)-2-thiazolyl]hydrazone, L2 = 2-[4-(3-pyridinyl)-2-thiazolyl]hydrazone) and characterized by 1H-NMR, elemental analysis (EA), and infrared spectra (IR). The crystalline behavior of L1 and 1–3 were analyzed by X-ray diffraction. In the structure of 1, L1 acts as a bidentate agent coordinating the Zn2+ ion through the pyridine nitrogen and thiazole nitrogen, while L2 bonded in a 2D structure by coordinating Zn2+ through the nitrogen atoms of two pyridine rings in the structure of 2. Additionally, with Cd2+ ions as connection points and the spatial extension of L2, 3 possesses an intricate 3D metal–organic framework. The luminescent properties for the ligands and complexes were investigated. The in vitro antimicrobial and antitumor activities were evaluated against ten pathogenic bacterial strains and four human cancer cell lines. [ABSTRACT FROM AUTHOR]

Ce3 + doped L~ Ga5 Ot2 ( LuGG : Ce) nano phosphor was synthesized via co-precipitation method. Its structured parameters were obtained by Rietveld refinement method. The morphology of the as-synthesized nanophosphor was determined with Scanning Electron Microscope ( SEM) . Under 365 nm excitation, the emission spectrum exhibits an asymmetry broad band with central wavelength at 438 nm and this broad band can be deconvolved into two peaks with wavelength centers at around 426 nm and 470 nm, respectively. The chromaticity coordinate of LuGG: Ce is ( 0. 176 9, 0. 180 3), which corresponds to blue light emission. The results show LuGG: Ce is suitable for realizing blue light emission under UV excitation and thus has potential applications in the fields of UV -excited white light emitting diodes( LEDs). [ABSTRACT FROM AUTHOR]

Two coordination compounds, Cd2(Рtt)2Cl4(H2O)2 (Ι) and [Cd(Dpb)2Cl2]n · nH2O (II) (Рtt = 3-(pyrid-2-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolyl), Dpb = 1,4-bis(pyridin-3-ylmethoxy)benzene), were synthesized from hydro-solvothermal technique. Their structures have been characterized by infrared spectra, elemental analyses, single crystal X-ray diffraction analyses (CIF files CCDC nos. 1903141 (Ι), 1903138 (II)) and thermogravimetric analyses. Compound Ι is a dinuclear structure and II is a 1D chain. Moreover, the luminescent properties of Ι and II have been investigated with fluorescent spectra in the solid state, the two compounds display a strong fluorescent emission at room temperature and have potential applications as fluorescent-emitting materials. [ABSTRACT FROM AUTHOR]

Two new 3D fluorescence metal–organic frameworks, namely [Zn2(p-bdc)4(dfdp)2]n (1) and [Cd2(p-bdc)4(dfdp)4]n (2) (p-H2bdc = 1,4-benzenedicarboxylic acid; dfdp = 4,4′-(2,5-difluoro-1,4-phenylene)dipyridine) have been synthesized under solvothermal conditions and structurally characterized by elemental analysis, infrared spectra, TG, UV–Vis spectra, fluorescence spectra, single crystal and powder X-ray diffraction. Compound 1 shows a 3D framework constructed by infinite [Zn2(p-bdc)4]n layer as nodes and the dfdp ligands as connected linkers. Compound 2 reveals a different structure from compound 1 which can be mainly attributed to different coordination numbers of dfdp linkers. Compared with compound 2, UV–vis spectrum of compound 1 is 25 nm red-shifted. Both compounds show strong solid-state luminescence at about 400 nm. Of particular interest is that the quantum yield of compound 1 is 11.73. Two novel 3D fluorescence metal–organic frameworks [Zn2(p-bdc)4(dfdp)2]n (1) and [Cd2(p-bdc)4(dfdp)4]n (2) have been synthesized and structurally characterized. Compound 1 show strong solid-state purple luminescence with 11.73 quantum yield (QY). [ABSTRACT FROM AUTHOR]

A one-dimensional Co(II) complex {[Co2(TIMB)(NO2–IPA)2(H2O)2]·H2O}n (1) (TIMB = 1,3,5-tris(2-methylimidazol-1-yl)benzene, NO2–H2IPA = 5-nitro-1,3-benzenedicarboxylic acid) is synthesized and characterized using single crystal X-ray diffraction, IR spectroscopy, and the elemental analysis. The single crystal X-ray diffraction analysis reveals that 1 is a 1D polymeric loop chain based on [Co4(NO2–IPA)4] and [Co2(TIMB)2] loops. Complex 1 exhibits an emission band at 358 nm (λex = 322 nm) and good catalytic photodegradation of RhB. Furthermore, there are antiferromagnetic interactions between the magnetic Co(II) centers in 1. [ABSTRACT FROM AUTHOR]

A prominent mixed-ligand system with rich "mix" features, which are rigid multicarboxylate O-donor ligands cooperating with flexible bisazole N-donor linkers, is explored to coordinate with Zn2+/Cd2+ centers. Two new entangled coordination polymers ([Cd(Hbtc)(bbi)] (1) and [Zn(btec)0.5(dtp)]·5H2O (2)) are gained. Complex 1 exhibits a fascinating 3D (3,5)-connected net with a Schläfli symbol of the (63.610) topology, and 3D nets penetrate into each other to give rise to twofold interpenetrations. Complex 2 displays a 2D layer with similar 9.9×12.0 Å2 hexagonal channels, the adjacent layers stacking with each other to form a 3D supramolecular structure. The effects and functions of the ligands in the complexes are discussed. Moreover, the thermal stabilities and fluorescence properties of complexes 1 and 2 are investigated. [ABSTRACT FROM AUTHOR]

Two new Zn(II) coordination polymers based on bis(imidazol), namely, [Zn(hba)2(bib)]n(1) and [Zn(NAA)(bib)1.5]n·nNO3−·3nH2O (2) (Hhba = 3-hydroxybenzoic acid, HNAA = 1-naphthyl acetic acid, bib = 1,4-bis(imidazol-1-yl)-butane) have been successfully synthesized under hydrothermal conditions. Their structures have been determined by single crystal X-ray diffraction analyses, elemental analyses, IR, TG and fluorescence spectrums. Complex 1 shows a one-dimensional zigzag chain structure. Complex 2 exhibits two-dimensional network structure. The intermolecular hydrogen bonding and π–π stacking interactions extend the complexes 1 and 2 into supramolecular architectures and play an important role in stabilizing complexes 1 and 2. Furthermore, complex 1 exhibits intense blue luminescence and appears to be a good candidate for novel hybrid inorganic–organic photoactive materials, while no photoluminescent response was observed for complex 2. In addition, we analyzed the Natural Bond Orbitals (NBO) of 1 and 2 using the PBE0/LANL2DZ method in the Gaussian 09 Program. The calculations showed the obvious covalent interaction between the coordinated atoms and Zn(II) ion. Two new Zn(II) coordination polymers based on bis(imidazol), namely, [Zn(hba)2(bib)]n(1) and [Zn(NAA)(bib)1.5]n·nNO3−·3nH2O (2) have been successfully synthesized under hydrothermal conditions. Their structures have been determined by single crystal X-ray diffraction analyses, elemental analyses, IR, TG and fluorescence spectrum. Complex 1 shows a one-dimensional zigzag chain structure. Complex 2 exhibits two-dimensional network structure. The intermolecular hydrogen bonding and π–π stacking interactions extend the complex 1 and 2 into supramolecular architectures and play an important role in stabilizing complex 1 and 2. In addition, we analyzed Natural Bond Orbital (NBO) of 1 and 2 in using the PBE0/LANL2DZ method built in Gaussian 09 Program. The calculation results showed the obvious covalent interaction between the coordinated atoms and Zn(II) ion. [ABSTRACT FROM AUTHOR]

Ceramic phosphor plates of Ce3+ doped Y 3 Al 5 O 12 :Ce (or YAG:Ce) are considered better wavelength converters for high power light emitting diode (LED) and laser diode (LD) lighting applications due to their significantly better thermal conductivity and heat resistance as compared to phosphor powder/epoxy films. Understanding the relationship between the microstructures of YAG:Ce ceramic phosphor plates and their luminescent properties is of importance to optimize their luminescent properties. In this work, we have found that the grain size of Ce3+ doped YAG ceramic phosphor plates has a significant effect on their luminescent properties. Our results show that ceramic phosphor plates with larger grains size can not only convert blue light to yellow light more efficiently, but also have better resistance to thermal quenching. When excited by a blue light source (peak wavelength of 455 nm, optical power of 24.75 W) generated by an LED COB, the ceramic phosphor plate with average grain size of 36 μm is found to have blue-to-yellow light conversion efficiency 46% higher than that of the sample with average grain size of 6 μm (309 lm W−1 vs 213 lm W−1). As they are heated from 300 K to 473 K, their emission intensities decrease by 15%, 19% and 21% for the samples with average grain sizes of 36 μm, 9 μm and 6 μm, respectively. [ABSTRACT FROM AUTHOR]