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Two cobalt metal–organic frameworks (Co-MOFs), [Ch]2[Co3(BDC)3Cl2] (1) and [Ch]2[Co3(BDC)4]·2DMU (2) (Ch+ = choline cation; H2BDC = terephthalic acid; DMU = 1,3-dimethylurea), were prepared through ionothermal reactions with deep eutectic solvents (DESs) of ChCl and DMU as the reaction media. The 1/GCE electrode with better current response was selected as the electrocatalyst. The detection performance of the 1/GCE electrode towards glucose is excellent with a wide linear range of 10–1200 μmol L−1, a detection limit of 3.2 μmol L−1 (S/N = 3), and a rapid response less than 3 s in 0.01 mol L−1 NaOH. 1 also exhibits high anti-interference with the existence of D-Man, D-Fru, DL-AA, and BA, long-term stability of 15 days and reproducibility for glucose detection. 1 was utilized to detect glucose in human serum and orange juice. The found glucose concentrations are very close to the added glucose concentrations in the selected situations with low RSD and high recoveries. This demonstrates that as a non-enzymatic glucose sensor, 1/GCE can detect glucose with high accuracy and reliability in different environments.

Fabricating highly efficient electrocatalysts for electrochemical hydrogen generation is a top priority to relief the global energy crisis and environmental contamination. Herein, a rational synthetic strategy is developed for constructing well-defined FeP-CoMoP hierarchical nanostructures (HNSs). In general terms, the self-supported Co nanorods (NRs) are grown on conductive carbon cloth and directly serve as a self-sacrificing template. After solvothermal treatment, Co NRs are converted into well-ordered Co-Mo nanotubes (NTs). Subsequently, the small-sized Fe oxyhydroxide nanorods arrays are hydrothermally grown on the surface of Co-Mo NTs to form Fe-Co-Mo HNSs, which are then converted into FeP-CoMoP HNSs through a facile phosphorization treatment. FeP-CoMoP HNSs display high activity for hydrogen evolution reaction (HER) with an ultralow cathodic overpotential of 33 mV at 10 mA cm-2 and a Tafel slope of 51 mV dec-1 . Moreover, FeP-CoMoP HNSs also possess an excellent electrochemical durability in alkaline media. First-principles density functional theory (DFT) calculations demonstrate that the remarkable HER activitiy of FeP-CoMoP HNSs originates from the synergistic effect between FeP and CoMoP.

A chemical oxidation process of aniline and a following deposition prepared polyaniline-nickel foam (PANI-NF) substrate. M(OAc)2∙4H2O (M = Co2+ and Ni2+, OAc− = acetate) reacted with 2,6-naphthalene dicarboxylic acid dipotassium (K2NDC) and in-situ deposited on the surface of PANI-NF to produce CoNi-NDC/PANI-NF composite. The reaction conditions of CoNi-NDC/PANI-NF were optimized as Co2+ and Ni2+ reacting at the starting ratio of 3:2 at 60 °C for 20 h with the presence of PANI-NF. SEM images revealed that CoNi-NDC/PANI-NF sheets distributed uniformly on the surface of PANI-NF substrate. Compared to CoNi-NDC/NF, with PANI adhered, CoNi-NDC/PANI-NF sheets grew much smaller and distributed more uniformly. Also, CoNi-NDC/PANI-NF exhibited better electrocatalytic activities toward oxygen evolution reaction (OER) (with an overpotential of 323 mV at 10 mA/cm2), and a remarkable reaction kinetics (with a Tafel slope of 73.3 mV/dec). CoNi-NDC/PANI-NF shows horizon I-t curves for 20 h at 10 and 100 mA/cm2, indicating a high durability without degradation of the OER performance. Compared to most recently reported MOF-based composites, lower or comparable overpotential and Tafel slope of CoNi-NDC/PANI-NF indicate it is a potential noble-metal-free electrocatalyst for OER.

The fabrication of an efficient bifunctional electrocatalyst towards alkaline overall water splitting is challenging, but in high demand. Herein, we report the construction of Mo-doped Ni2P hollow nanostructures through a solvothermal method and in situ phosphorization strategy. The Mo-doped Ni2P hollow nanostructures demonstrate excellent hydrogen evolution reaction (HER) activity in 1.0 M KOH solution with a low cathodic overpotential of 81 mV (10 mA cm−2, glassy carbon) and a small Tafel slope of 53.4 mV dec−1. First-principles density functional theory calculations reveal the mechanism of the alkaline HER. For pristine Ni2P, the P site serves as the active center. After Mo doping, the active center transforms to a bridging Mo–Ni site and the corresponding Gibbs free energy of H* absorption (ΔGH*) decreases from 0.33 eV (P site) to 0.21 eV (bridging Mo–Ni site). The optimal active site with a smaller ΔGH* can accelerate the charge transfer process for H* intermedium and H2 production. For the oxygen evolution reaction (OER), the Mo-doped Ni2P hollow nanostructures require 270 mV to attain 20 mA cm−2 (glassy carbon), with a small Tafel slope of 68.5 mV dec−1. Impressively, both the HER and OER catalysis exhibit durable performance in alkaline electrolyte. When the Mo-doped Ni2P hollow nanostructures are applied as bifunctional electrocatalysts for alkaline overall water splitting, the demanded cell voltage is only 1.54 V (10 mA cm−2, nickel foam).

For alkaline fuel cell cathode reactions, it is crucial to develop new catalysts with excellent catalytic performance. Two-dimensional molybdenum disulfide nanosheets have proven to be effective electrocatalysts, especially in hydrogen evolution reactions. However, MoS2 has been less researched as a potential electrocatalyst for oxygen reduction reaction (ORR). The introduction of vanadium atoms by chemical doping significantly increases the ORR activity of the MoS2 nanosheets, which is greatly improved compared to the bulk MoS2. The vanadium heteroatoms can not only change the electrical properties and band structure of the pristine materials, but also provide a rich active site for the catalysis.

The ionothermal reaction of EuCl3 with 4,4′-biphenyldicarboxylic acid (H2BPDC) produced a 3D fluorescence coordination polymer (CP), [PMI]2[Eu2(BPDC)3Cl2] (1). 1 was dispersed onto the bandage, and further infiltrated by polyvinylidene fluoride (PVDF) to give a mixed matrix 1@PVDF/bandage composite film (1-film). The fluorescence and the morphology indicate 1-film can emit red fluorescence and the CP particles are on the surfaces of bandage fabrics with the adhesion of PVDF. The fluorescence of 1-film can be quenched by different amines in the order of aliphatic amine > aromatic amine > alcohol amine > amide, which concerns with the amine sizes. 1-film shows a fast response and selective sensing to aniline vapor, suggesting it may be a fluorescence turn-off sensor to aniline vapor.

In this work, an airtight solid-state strategy was developed for the synthesis of K2TiF6:Mn4+ phosphor without the usage of high concentration HF solution. By heating K2TiF6, K2MnF6 and KHF2 in a sealed container at 474 K for hours and then washing the as-synthesized samples several times, K2TiF6:Mn4+ phosphor was obtained. The microstructure, luminescent properties of the phosphor were investigated systemically. The reaction mechanism were investigated and discussed in detail. KHF2 is the key role to obtain the red phosphor, which provides additional pressure and HF gas atmosphere, works as reaction intermediate and contributes to Mn4+ doping into K2TiF6 host. By using as-prepared K2TiF6:Mn4+ phosphor as a red componet for warm W-LEDs, the high color rendering index (Ra = 84) and low color temperature (CCT = 3621 K) device performance proved that this environmental friendly synthesis method would be an efficient way to produce red fluoride phosphor for W-LEDs.

The detection of pH and water is of significance in natural and production processes. The ionothermal reactions of 4,4′-oxybisbenzoic acid (H2OBA) with Eu3+ and Tb3+ produced [M(OBA)(H2O)Cl] (M = Eu3+ (1) and Tb3+ (2)) and heteronuclear [Eu0.05Tb0.95(OBA)(H2O)Cl] (3). 3 emits the combined characteristic transitions of Eu3+ and Tb3+. Its energy transition processes can be disturbed by pH and water. The emission colors of 3 follow pH changes. It emits blue light when pH = 1–2, in which OBA2− turns into H2OBA based on the acid–base equilibrium. When pH = 3–11, the emission colors change from green to orange and ITb/IEu exhibits a linearity of ITb/IEu = 6.7482–0.5971·pH; the emissions are quenched at pH = 12–13, due to OH− destroying the delocalized conjugated system of 3. 3 shows a fluorescence response to water with a linearity of ITb/IEu = 0.30353 + 0.15042·VH2O% within 0–0.8% VH2O%. The green (G) and red (R) color intensities of the paper-based MOF sensor of 3 reveal a trinomial fitting equation of G/R = 4.16334 − 1.23014·pH + 0.14036·pH2 − 0.00551·pH3 when pH = 3–11. 3 can be used as a ratiometric fluorescent sensor to detect pH and water and the paper-based MOF sensor can also be used in on-site pH detection.

We present a strategy for selecting an optimal material in a particular temperature range by investigating the relationship between the absolute sensitivity ( Sa) and energy gap (Δ E), as well as the relationship between Sa and temperature on the basis of Yb3+/Ln3+ (Ln = Er3+, Ho3+)-codoped Ba2In2O5 phosphors. Through an investigation of optical performance, the phosphors exhibit near-infrared (NIR) downshifting and visible upconversion (UC) emissions under 980 nm excitation. The NIR spectral range from 700 to 1800 nm is referred to as the "biological window". The NIR emission peaks of Er3+ and Ho3+ are located at 1550 nm of the third biological window and 1192 nm of the second biological window, respectively. The temperature sensing behaviors based on the UC luminescence in Yb3+/Ln3+-codoped Ba2In2O5 phosphors are recorded by the fluorescence intensity ratio (FIR) technique in the temperature range from 303 to 573 K. The Ba2In2O5:Er3+/Yb3+ sample is usable at temperatures above 350 K, and the Ho3+/Yb3+-codoped Ba2In2O5 phosphor is suitable at temperatures below 350 K in our experimental region. The above results show that the Ba2In2O5:Ln3+/Yb3+ phosphors could be promising candidates for optical temperature sensors and applications in the biological imaging field.

Transition metal phosphides (TMPs) are considered to be highly-efficient electrochemical catalysts, which have extraordinary capabilities to relieve the energy crisis and have gradually become prime candidates for application in energy conversion and storage devices. In this contribution, we report the preparation of porous Ni2P nanosheets in a controllable manner using NiO–MOF-74 as precursors, followed by a conventional phosphorization strategy. The porous Ni2P nanosheets exhibit excellent electrocatalytic performance towards the hydrogen evolution reaction (HER) with a low overpotential of 168 mV at a current density of 10 mA cm−2 in 1.0 M KOH and a small Tafel slope of 63 mV dec−1. The overpotential and Tafel slope of porous Ni2P nanosheets for the oxygen evolution reaction (OER) are 320 mV (10 mA cm−2) and 105 mV dec−1, respectively. In addition, both the HER and OER measurements demonstrate that porous Ni2P nanosheets have superior electrochemical stability in alkaline solution. The desirable electrocatalytic properties of the porous Ni2P nanosheets may be due to their larger surface area and favorable electrical conductivity. The porous structures of the Ni2P nanosheets provide pathways for electron conduction, which facilitates electron transfer and accelerates bubble (H2 and O2) diffusion on the surface of the electrode.

Ionothermal reactions of 1,3,5-benzenetricarboxylate acid (H3BTC) and Ni(NO3)2, Co(NO3)2 and Cu(NO3)2 gave two discrete 32-membered ring-like allomers, [M2(HBTC)2(NH2CONH2)2(H2O)4]·3H2O (M=Ni(1), Co(2)) and one layered [Cu2(BTC)Cl(H2O)4] (3). The weak interactions in 1 can be deconstructed to some degree in ion exchange by exploring the factors of divalent and trivalent metal species, metal concentration and soaking time, which are demonstrated by PXRD and N2 absorption. Cu2+ has the highest N2 adsorbance when soaking with 1, and 1 can keep structure stable when Cu2+ below 0.16 mol L−1 and the soaking time within 24d. As Cu2+ beyond 0.16 mol L−1 and the soaking time beyond 24d, the structure of compound 1 starts to transform with the crystal morphology from clear pale green to opaque blue. Ionothermal reactions of compound 1 with different Cu2+ amounts obtained Ni2+-Cu2+ hetero complexes, whose PXRD patterns are similar to that of 3 and EDS indicates Cu2+% increases with Cu2+ additions and close to 100% as Cu2+ being 1.6 mmol. It suggests that 3 is a controlled product and Cu2+ can transform discrete compound 1 into 2D compound 3.

Ionothermal reactions of 1,4-benzenedicarboxylic acid (H2BDC) and 4,4′-biphenyldicarboxylic (H2BPDC) with Mn(OAc)2 resulted in 12 compounds divided into four kinds of structural models: [RMI]2[Mn3(BDC)3X2] (1–5, type A), [EMI]2[Mn3(BPDC)4] (6, type B), [RMI]2[Mn2(BPDC)3(H2O)3] (7–9, type C) and [RMI]6[Mn9(BPDC)9(HBPDC)2(OAc)4] (10–12, type D). A combination effect of ligands and IL components can be observed in the structural construction, which also is reflected in the properties of thermal stability and fluorescence. The decomposition temperatures of Mn–BDC compounds are higher than those of Mn–BPDC compounds. The decomposition temperatures decrease with the alkyl chain in [RMI]+, due to a +I inductive effect. The maximum emissions of compounds 1–5 and 6–12 located at ca. 410 or 407 nm are assigned to ILCT of H2BDC and H2BPDC ligands, respectively.

Hydrothermal syntheses of 2-carboxyethyl(phenyl)phosphinic acid (H2CEPPA) with Bi(NO3)3 and Cd(NO3)2 produce two layered complexes [Bi2(μ3-O)(CEPPA)2] n (1) and [Cd(HCEPPA)2] n (2). Compound 1 is comprised of [Bi4(μ3-O)2(POO)4(COO)4] SBUs which grow into a double wave-like 2D layer with–CH2CH2–spacers. Compound 2 crystallizes in the orthorhombic noncentrosymmetric space group Pca21, exhibiting a double lattice-like layer. Through edge-to-face d∙∙∙π stacking, a 3D supramolecular framework is formed based on 2D lattices. Topological analyses indicate that 1 and 2 have sql (or Shubnikov tetragonal plane net) and kgd (or Shubnikov (3.6.3.6) plane net) topological networks respectively. 1 and 2 are isolated as single crystal pure phases, which is confirmed by powder XRD. TGA shows high thermal stabilities with decomposition temperatures of 1 and 2 being 373 and 303°C respectively. The fluorescent spectra exhibit fluorescence quenching in 1 and sharp emission at 292 nm in 2, which is assigned to intraligand emission.

Eight kinds of 1-methyl-3-alkylimidazolium halide [RMI]X (R=ethyl (E), propyl (P), butyl (B) and amyl (A); MI = imidazolium; X= Cl−, I−) ionic liquids (ILs) were used as reaction media and obtained a series of 2D [RMI]2[Co3(BDC)3X2] frameworks through the ionothermal reactions of 1,4-benzenedicarboxylic acid (H2BDC) with Co(NO3)2·6H2O. The 2D [RMI]2[Co3(BDC)3X2] frameworks exhibit a same (3,6) topology network with [RMI]+ cations locating in the interlayer space. [RMI]+ cations play a template role in the structure constructions, whose influence combining with the effect of X− anions pass to the TG behaviors. The decomposition temperatures of the [RMI]2[Co3(BDC)3X2] frameworks decrease with the alkyl chains in [RMI]+ cations, and the compounds containing Cl− show higher thermal stabilities than those with I−. However, compounds 1–8 exhibit two similar broad emissions at ca. 380 and 390 nm, assigned to ILCT. The RMI+ templates and the X− anions do not exert their influence on the fluorescence.

Seven Eu-(H)BDC compounds, [RMI][Eu2(BDC)3Cl] (R = ethyl (1), propyl (2), butyl (3), H2BDC = 1,4-benzenedicarboxylic acid), [EMI]2[Eu2(BDC)3(H2BDC)Cl2] (4), [Eu(BDC)(HCOO)] (5), [Eu(BDC)Cl(H2O)] (6) and [Eu3(BDC)4Cl(H2O)6] (7), were synthesized under ionothermal conditions. Compounds 4 and 6 behave as potential highly selective turn-off fluorescent sensors for aniline, which can be detected in mixtures of aniline with contrast organic amides or alkylbenzenes. Fluorescence quenching can be observed when compounds 4 and 6 mix with the samples containing aniline. Compounds 4 and 6 show basically unchanged emission intensities and rapid response to aniline after ten recycling tests, suggesting that the compounds have high stable recycle repeatabilities.

Tetragonal Yb3+/Er3+/Tm3+ tri-doped AgGd(W,Mo)2O8 phosphors were prepared by the high-temperature solid-state method. When the phosphors were excited at 980 nm, the UC emission of blue at 475 nm, green at 525 and 550 nm, and red at 656 nm were corresponding to the 1G4 → 3H6 transition of Tm3+ ions, the 2H11/2,4S3/2 → 4I15/2 transitions of Er3+ ions, and the 4F9/2 → 4I15/2 transition of Er3+ ions, respectively. The blue UC emissions originate from a three-photon mechanism, while the green and red ones of Er3+ from two-photon process. The UC emission color of the Yb3+/Er3+/Tm3+ tri-doped AgGdW2O8 samples switched from green to white, and then to red depending on the concentrations of Er3+ and Tm3+. After doping with Mo(VI), tetragonal AgGdW2O8 was transformed into tetragonal AgGdMo2O8, resulting in a slightly enhanced UC luminescence intensity with the favor of the red emission of Er3+ ion.

With their unique properties and potentials in several critical applications, highly crosslinked and conductive nanofibrous films (HCC-NFs) have attracted broad attentions recently. However, it is still a great challenge to produce high-performance and uniform HCC-NFs with controllable thickness on a large-scale. Electrospinning could be used to fabricate nanofiber films, but it falls short in creating intimate mechanical and electrical joints between adjacent nanofibers for crosslink. Herein, a new strategy inspired by the fabric shrinking when drying was applied to produce HCC-NFs. Hydrophilically-engineered electrospun polyacrylonitrile (PAN) nanofiber film was dip-coated in a water solution of PEDOT:PSS, and was then dried naturally. By preventing contraction of the film in its lateral plane while allowing its thickness shrinking, the capillary effect during water evaporation resulted in collapse of the large pore volume in the film and the subsequent joint formations between PEDOT:PSS-coated PAN nanofibers, which are further cemented together by the conductive polymer coating. The electrochemical, electrical and mechanical properties of such fabricated HCC-NFs were studied, and they were successfully applied as electrodes to demonstrate high-rate supercapacitors and as a flexible porous material for electromagnetic interference (EMI) shielding. The studies suggest HCC-NFs produced by this facile method have promising prospects in several applications.

Fiber-shaped templates that can be easily loaded with a large amount of hydrophilic and/or lipophilic active materials in a facile process like dip coating, will find many applications including for wearable electronics. Here, macroscale amphiphilic aerogel-like fiber, made from electrospun glycerol-functionalized polyacrylonitrile (PAN) nanofibers (GPN) on a centering metal wire, is reported. With its high porosity, large void space, and both hydrophilic and lipophilic characteristics, this unique GPN aerogel fiber can absorb a large amount of aqueous and oil solutions dispersed with different active materials. In particular, poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PP) represented water-soluble active material is selected to prepare PP-loaded fiber, which is further coated with polyaniline (PANI). The PP@GPN/Ti and PANI@PP@GPN/Ti fibers are studied as electrodes for flexible yarn-shaped solid-sate supercapacitors. A fiber-length-specific capacitance as large as 243 mF cm−1 is measured at 0.1 mA cm−1, one of the best capacitances ever reported for fiber supercapacitors. Colza oil is also tested as a representative oily solvent to investigate the load capacity of GPN aerogel fiber and a mass loading of 124 μl cm−1 is achieved. These results suggest that our unique amphiphilic aerogel fiber could act as a carrier loading a large amount of active masses for many novel applications.

Hydrogen peroxide (H2O2) plays an important role in physiological processes. In this work, a Cu-based metal-organic framework (Cu-MOF) was synthesized under ionothermal condition, further grafted with ammoniated Au nanoparticles (AuNPs-NH2) to prepare AuNPs-NH2/Cu-MOF composite. Glassy carbon electrode (GCE) was modified with AuNPs-NH2/Cu-MOF to prepare AuNPs-NH2/Cu-MOF/GCE electrode, which was used in H2O2 detection. AuNPs-NH2/Cu-MOF/GCE exhibits itself as a highly sensitive and selective electrochemical enzyme-free sensor for H2O2 detection. A quantitative detection to H2O2 can be found with a wide linear response toward H2O2 concentrations ranging 5–850 μM, its limit of detection (LOD) is as low as 1.2 μM with a high sensitivity of 1.71 μA/cm2·μM. AuNPs-NH2/Cu-MOF/GCE sensor has been applied to determine H2O2 effectively in human cervical cancer cells by adding the ascorbic acid as the stimulant. Our work presented a AuNPs-NH2/Cu-MOF/GCE composite electrode which is a promising enzyme-free electrochemical sensor for quantitive H2O2 detection in human cervical cancer cells.

ObjectivesA significant number of researches have evidenced that occupational lead (Pb) exposure increased risks of cardiovascular disease. However, evidences about the potential effects of Pb on the cardiac conduction system are sparse and inconclusive. Besides, ryanodine receptors (RyRs) induced dysfunction of cardiac excitation contraction coupling which is considered to be one of the mechanisms in cardiovascular diseases. Therefore, we examined the association between occupational Pb exposure and ECG conduction abnormalities, as well as RyRs in Pb-induced ECG abnormalities.MethodsWe investigated 529 Pb smelter workers, and measured blood lead (BPb), zinc protoporphyrin (ZPP), ECG outcomes and RyR expression levels. Based on BPb levels, the workers were divided into three groups: the BPb not elevated group, the BPb elevated group and the Pb poisoning group. Descriptive and multivariable analyses were performed.ResultsCompared with the BPb not elevated group, the Pb poisoning group had a higher incidence of high QRS voltage, and a lower level of RyR1 gene expression (pConclusionsOur study provided evidences that occupational exposure to Pb may be associated with worse ECG outcomes (high QRS voltage), which might be related to decreased levels of RyR1.

A large number of studies have evidenced that developmental neurotoxicity induced by lead (Pb) is related to oxidative injury. Furthermore, recent studies have found that developmental Pb exposure can induce neurodegeneration in old age. Because of the common presence of Pb in the environment, humans are exposed to this metal throughout their lifetime. However, few studies have explored the changes in lifespan profiles of neurotoxicity, as well as oxidative stress following lifetime Pb exposure. In the present study, rats were exposed to lead acetate from their embryonic stage to old age. Dynamic changes in neurodegeneration, oxidative stress, and endoplasmic reticulum (ER) stress in the brains at postnatal week 3 (PNW3, weaning), 41 weeks (PNW41, adulthood) and 70 weeks (PNW70, old age) were investigated. Pb exposure resulted in neurodegeneration with decreased neuronal densities and brain volumes in PNW3 and PNW70 rats; however, no significant changes occurred in PNW41 rats based on thionine stain analysis and magnetic resonance imaging (MRI) scans. Expression of the ER stress protein glucose-regulated protein 78 (GRP78) increased in Pb-exposed rats, which was associated with high levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in rat brains after Pb exposure in PNW3 and PNW70 rats. Our findings suggested that lifetime Pb exposure induced neurodegenerative injuries that began to occur in infancy, were relieved in adulthood, but intensified in old age. The critical periods for prevention or intervention in neurodegenerative diseases induced by Pb exposure occurred in early life.

Thermosensitive fluorescent [Eu(NDC)(H2O)Cl] (1) (H2NDC = 2,6-Naphthalene dicarboxylic acid) was fabricated with polyether sulfone (PES) into composite films. 40% 1@PES film showed highly sensitive and repeatable thermal sensor properties in an alarm device.

The research on the impacts of modified TiO2 nanoparticles (NPs) on interfacial tension (IFT) is in its infancy. Our work focuses on the IFT of the modified TiO2 and Gemini surfactant N,N,N′,N′-tetramethyl-N,N′-dimyristyl-1,2-ethane diammonium dichlone (YND1233) complex solutions for reservoir stimulation purposes. The factors of YND1233, modified TiO2 NPs, temperature, aging stability, adsorption loss, and mineralized degree were explored with the comparison of unmodified TiO2 NPs and YND1233 as contrast samples. The results indicate that the dynamic IFTs decrease and then increase with the concentrations of YND1233 and modified TiO2 NPs, and the minimum IFT appears at 0.200 and 0.010 wt%, respectively. YND1233/modified TiO2 complex solutions show lower and more stable IFTs, better temperature resistance, longer aging time, and lower adsorption on the surface of quartz sand. The modified TiO2 NPs and YND1233 in the YND1233/modified TiO2 complex solution can be adsorbed to the interface and decrease the I...

A new 3D Cd-triazolate MOF compound [Cd(Hatrz) (SO4)] (1) (Hatrz = 3-amino-1H-1,2,4-triazole) was obtained from in situ decarboxylication of 5-amino-3-carboxyl-1,2,4-triazole (H2atrc) under the hydrothermal reaction of CdSO4 with H2atrc. Compound 1 features itself a Hatrz-supporting 3D architecture based on the connection of inorganic [CdSO4] layers with Hatrz spacers. Cd(II) atom, SO 4 2 − and Hatrz dummied as 6-, 4- and 2-connected nodes respectively, compound 1 can be simplified to a (2,4,6)-connected {44.62.88.12}{44.62}{8} topological network. The thermal stability of 1 is up to ca. 402 °C, and the fluorescence of 1 shows an emission at 366 nm, originating from SO 4 2 − → Cd transfer. PXRD of compound 1 confirms the phase purity of the bulk sample. FT-IR spectrum of 1 is in accord with the structure analysis.

A series of CaMoO4:Eu3 + with diverse morphologies were prepared via co-precipitation method with different organic additives, which were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence (PL) spectroscopy. The results show that the organic additives do not change the crystal structures of CaMoO4:Eu3 + phosphors, but greatly influence the morphologies and PL intensities of CaMoO4:Eu3 + phosphors. The morphologies of CaMoO4:Eu3 + phosphors were tuned through the fundamental experimental conditions such as the surfactants and binary mixed solvents. The CaMoO4:Eu3 + particles appear as diverse morphologies of leaf- and flower-like microspheres, single and twinned hemispheres, etc., with diameters ranging from 50 nm to 8.0 μm. In our work, six types of surfactants, and two kinds of binary solvent system of EG/H2O and DMF/H2O were investigated on their effect on the morphologies, particle sizes and PL properties of the samples. The red emission of CaMoO4:Eu3 + phosphors locate at 614 nm excited at 395 nm, assigned to Eu3 + characteristic emission.

Uniform yolk–shell Au@Y2O3:Eu3+ sub-microsphere phosphors were successfully prepared through urea-assisted homogeneous precipitation method by using carbon spheres as templates. The structure, morphology, photoluminescence and photocatalytic properties of the as-prepared Au@Y2O3:Eu3+ microspheres were subsequently investigated. The results indicate that the Y2O3:Eu3+ microspheres can be well indexed to the cubic Y2O3 phase. Furthermore, the Au@Y2O3:Eu3+ microsphere is able to maintain the spherical morphology and good dispersion of the carbon sphere template. The yolk–shell Au@Y2O3:Eu3+ spheres exhibit the bright luminescence of Eu3+. The photocatalysis of the Y2O3:Eu3+ shell and the Au core occur simultaneously, thereby significantly decreasing the absorbance of rhodamine B solutions. This work provides a strategy for inhibiting aggregation of noble metal nanoparticles during high-temperature calcinations and leaching of noble metal nanoparticles into a solution through a mesoporous shell. Ultimately, a multifunctional nanostructure was obtained by combining a specific metal core with an oxide shell.

A new class of Mn4+ activated alkali-metal hexafluoride red phosphors are emerging for white light-emitting diodes because of their sharp red line 2Eg → 4A2g emissions (600–650 nm) excited by irradiation of 4A2g → 4T1g (320–380 nm) and 4A2g → 4T2g (380–500 nm) transitions. However, these phosphors have the drawbacks of difficult control of the Mn valence state during synthesis and lack of underlying mechanisms for structure–photoluminescence relationships. In this study, we explore a novel, highly productive route to the quantifiable synthesis of K2GeF6:Mn4+ by the chemical co-precipitation method at room temperature. The prepared yellowish K2GeF6:Mn4+ powders exhibit a hexagonal shape and high crystallinity without significant defects. The photoluminescence thermal stability and white light-emitting diodes applicability of K2GeF6:Mn4+ suggest that it is a promising commercial red phosphor because of its efficient emission intensity, high color purity and excellent thermal stability. Structural analyses and theoretical calculations reveal that the red shift of the K2GeF6:Mn4+ red phosphor compared with K2SiF6:Mn4+ is due to the longer Ge–F distance and lower effective Mulliken charge of F ions in coordination environments of the MnF62− octahedron. The split feature in K2GeF6:Mn4+ is due to the hexagonal distortion in the host. The structure–photoluminescence mechanism is predicted to be general in hexafluoride red phosphors to tune the optical properties through cationic substitutions and crystal structure adjustments.

Two types of 2D [RMI]2[Zn3(BDC)3X2] (Type A) and 3D [Zn(BDC)(H2O)] (Type B) (H2BDC = 1,4-benzenedicarboxylate acid) compounds were synthesized with three kinds of 1-alkyl-3-methyl imidazolium halide ([RMI]X) ionic liquids. Type A is the primary structure model showing a (3,6) network. Type B can be obtained from [BMI]Cl, [AMI]Cl and [AMI]Br media, showing a 4,4-connected {4(2)·8(4)} network. The structure, TG, and fluorescence analyses demonstrate the combination effect of the RMI(+) templating effect and X(-) controlling the structure types. The boundary between Types A and B is from [PMI]Cl, via [BMI]Br, to [AMI]I as the reaction media. The decomposition temperatures of the compounds in Type A decrease with increased RMI(+), while X(-) anions exert the influence that compounds containing Br(-) supply the highest thermal stability. Similarly, with increased RMI(+), or X = I(-), the compounds show red shifts compared to the emissions of the ligand.

Ca0.28Ba0.72Nb2O6 (CBN28) ceramics with addition of CeO2 and La2O3, were prepared by the conventional ceramic fabrication technique. XRD results showed that the single tungsten bronze structure of CBN28 was not changed by adding CeO2 or La2O3. SEM results indicated that both CeO2 and La2O3 dopants were effective in inhibiting the grain growth and suppressing the anisotropic growth behavior in tungsten bronze structure. It was also found that both two kinds of dopants had remarkable effects on the dielectric and ferroelectric properties of CBN28 ceramics. Compared with CBN28 ceramics, the dielectric constant around room temperature er, dielectric loss tan δ, the degree of diffuseness γ and coercive field Ec were all ameliorated when doping proper amount of CeO2 or La2O3. The comprehensive electric performance was obtained in CBN28–0.3 wt% CeO2 and CBN28–0.4 wt% La2O3 ceramics. Besides, the underlying mechanism for variations of the electrical properties due to different dopants was explained in this work.

Hyperfine red phosphors composed of Eu3 + ion-doped CaMoO4 with varying morphologies were prepared via a facile precipitation method at room temperature without any organic additives. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and photoluminescence (PL) spectroscopy were used to characterize the synthesized products. The morphologies of the prepared CaMoO4:Eu3 + phosphors were controllable by adjusting the fundamental experimental conditions such as the pH value of the initial solution, the molar ratios of Ca(NO3)2/(NH4)6Mo7O24, the concentrations of the reactants, the precipitation reagents, and the raw materials. The formation process of CaMoO4:Eu3 + based on the aging time is discussed in detail. The room-temperature photoluminescence properties of the as-prepared CaMoO4:Eu3+ phosphors under diverse experimental conditions were also studied systematically, and their emission spectra showed emission characteristic of Eu3 +.

Ca0.28Ba0.72Nb2O6 (CBN28) ceramics with different content of CuO were prepared by the conventional ceramic fabrication technique. The effects of CuO content on the phase structure, microstructure, dielectric and ferroelectric properties of obtained CBN28 ceramics were investigated. XRD results showed that pure tungsten bronze structure was obtained in all ceramics and CuO additive could accelerate the phase formation at lower temperatures. The CuO aid was effective for the uniform grain size in CBN28 ceramics, as it could facilitate the sintering behavior and suppress the anisotropic growth behavior obviously. The dielectric and ferroelectric properties of CBN28 ceramics depended greatly on the CuO content. Curie temperature T c and dielectric loss tanδ both shifted downward, whereas the maximum dielectric constant e m and the dielectric constant around room temperature e r all increased initially and then decreased as x increased from 0.1 to 0.4 wt%. Normal ferroelectric hysteresis loops could be observed in all compositions, and the remnant polarization P r decreased gradually. It was found that the comprehensive electric performance was optimized in CBN28-0.2 wt% CuO ceramics: e r = 453, e m = 3,371, T c = 226 °C, tanδ = 0.048, P r = 4.72 μC/cm2 and E c = 13.81 kV/cm, showed that CuO sintering aid could not only ameliorate the sintering behavior but also improve the electrical properties.

In the binary system (1−x)Li2SO4–xNa2SO4, the solid–solid phase transitions and energy storage properties of Li2SO4, Na2SO4, the binary compound LiNaSO4 and two eutectoids (E1: 0.726Li2SO4–0.274Na2SO4; E2: 0.03Li2SO4–0.97Na2SO4) were investigated by X-ray diffraction and differential scanning calorimetry. Li2SO4 has a solid–solid phase transition at 578 °C with the transition enthalpy 252 J g−1. The binary compound LiNaSO4 gives a slightly lower enthalpy value, 214 J g−1 and its transition temperature is clearly reduced to 514 °C. The transition enthalpy of the eutectoid E1 is maintained to 177 J g−1 and its transition temperature is further reduced to 474 °C. Li2SO4, LiNaSO4 and the eutectoid E1 are applicable phase transition materials because of their large transition enthalpies. The enthalpies of Na2SO4 and the eutectoid E2 are not very high (∼45 J g−1), but their transition temperatures are quite low (∼250 °C); thus their transition properties may be applied at such low temperatures.

To investigate the influence of ionic liquids on the structures and properties of the complexes, ionothermal synthesis of 1,4-benzenedicarboxylate acid (H2BDC) reacting with Co(NO3)2 with four different 1-alkyl-3-methylimidazolium bromides produced three layered metal–organic frameworks with the chemical formula [RMI]2[Co3(BDC)3Br2], (R = ethyl for 1; n-propyl for 2, and n-butyl for 3; MI = imidazolium) and a 3D architecture [AMI]2[Co3(BDC)4] (4) (A = amyl). Compounds 1–3 have the same (3,6) skeleton with [RMI]+ cations located in the interlayer space. Compound 4 grows into a 3D architecture based on BDC2− ligands linking similar 2D grids as those in 1–3. The [RMI]+ templates exert their influence on the diagonal sizes of the quadrilateral grids, the interlamellar spacing, and the solvent-accessible cavities through steric hindrance. By comparison of 1–3, the [RMI]+ templates also have an effect on the properties. As the alkyl chains in [RMI]+ increase, the decomposing temperatures increase, emission peaks around 400 nm blue shift, and the cavities of 1–3 decrease. 1–3 exhibit ferromagnetism with similar magnetic parameters, while 4 reveals antiferromagnetism.

Wire-shaped solid-state supercapacitors (WSSCs) receive ever-growing interest for developing electronic textile. How to achieve a high active mass loading with a suitable mesoporous structure and strong adhesion on a bare metal wire are a severe challenge faced by the development of practical WSSCs, which must meet requirements such as high energy and power densities, fast rate capability, as well as flexibility and stability. Here, a new strategy to synthesize the wire-shaped electrode with excellent electrochemical and mechanical performances is reported using a soft aerogel template in a facile dip coating process. Hydrophilically engineered polyacrylonitrile nanofibers by adding glycerol were electrospun on a Ti metal wire to form the sacrificial aerogel template with a huge void volume, in which poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) solution was dip coated to achieve a large mass loading. The capillary effect in the subsequent natural drying process, slow dissolution of the template in a solvent, and PSS etching, together lead to a mesoporous PEDOT thick coating network formed on the metal wire with a high conductivity, strong mechanical strength and intimate interface adhesion. The resulted WSSCs based on Ti/PEDOT electrodes, exhibited a fairly wide potential window, large specific capacitance, ultrahigh rate capability and energy/power densities.

Barium orthotitanate (Ba2TiO4) was prepared by heating at 1250°C for 2 h. The thermal stability of Ba2TiO4 and the phase transformation between the low-temperature monoclinic polymorph (β-Ba2TiO4) and the high-temperature orthorhombic polymorph (α′-Ba2TiO4) were examined by X-ray diffraction. Ba2TiO4 can be corroded by CO2 below 700°C forming BaCO3 and BaTiO3, which is reversible above 750°C. A martensitic transformation from β-Ba2TiO4 to α′-Ba2TiO4 starts at ∼100°C and ends at ∼220°C in heating process. The transformation hysteresis loop is ∼200°C. α′-Ba2TiO4 can be stabilized to room temperature by doping small amount of aliovalent ion Nd3+ (1.5 mole%) or relatively large amount of isovalent ion Sr2+ (10 mole%). After annealing the doped samples at low temperatures (e.g., below 1100°C), for the Nd-doped sample, α′-Ba2TiO4 can be partially transformed to β-Ba2TiO4, whereas the Sr-doped sample is stably kept as α′-Ba2TiO4.

A new 1D cadmium coordination polymer [Cd(PhCOO)2(bbbm)] n (1) (bbbm = 1,1′-(1,4-butanediyl)bis-1H-benzimidazole ) is synthesized under hydrothermal conditions and characterized by elemental analysis, IR, TG, and X-ray single-crystal diffraction. Compound 1 crystallizes in the triclinic system, space group P-1 with a = 10.4289(17) A, b = 12.5198(9) A, c = 12.6130(9) A, α = 118.4260(10)°, β = 95.1990(10)°, γ = 94.3820(10)°, V = 1428.8(3) A3, Z = 2. In the structure of 1, each cadmium center is six-coordinated in a strongly distorted octahedron by two N and four O atoms; an infinite one-dimensional linear chain was built by the flexible bbbm ligand that adopts a bis-monodentate bridging mode linking CdII atoms.

The relation between lead (Pb) and iron (Fe) becomes increasingly concerned because they are both divalent metals that are absorbed by the same intestinal mechanism, and Pb exposure and Fe deficiency in the developmental brain, as well as Fe overload in the aged brain, can cause cognitive deficits. However, the interaction between Pb exposure and Fe status in the brain has not been established. Therefore, in the current study, we examined the effects of maternal ingestion of Pb in drinking water during gestation and lactation on the Fe status and the expression of divalent metal transporter 1 (DMT1) and ferroportin 1 (FP1) in the brain of offspring. The offspring were followed through old age, with measurements taken at postnatal week 3 (PNW3), 41 (PNW41) and 70 (PNW70). Pb exposure increases the Fe content in the old-aged rats' brain, which might be not subjected to DMT1 mediating, but may be associated with the decrease expression of FP1. Furthermore, the effect of Pb on FP1 expression is regulated at transcriptional and posttranscriptional levels. The perturbation in Fe homeostasis may contribute to the neurotoxicology consequences induced by Pb exposure, and FP1 may play a role in Pb-induced Fe cumulation in the brain.

Based on three structurally related flexible bis(5,6-dimethylbenzimidazole) ligand, five novel metal–organic CdII coordination architectures: from 0D to 3D structures CdII complexes have been hydrothermally synthesized and structurally characterized, namely, Cd2I4(L1)2 (1), [CdCl2(L1)]n (2), [CdCl2(L2)]n (3), {[Cd(chdc)(L2)0.5]·H2O}n (4), {[Cd(pydca)(L3)0.5(H2O)2]·H2O}n (5) (where L1 = 1,2-bis(5,6-dimethylbenzimidazole)ethane, L2 = 1,3-bis(5,6-dimethylbenzimidazole)propane, L3 = 1,4-bis(5,6-dimethylbenzimidazole)butane, H2chdc = 1,4-cyclohexanedicarboxylic acid, H2pydca = pyridine-2,6-dicarboxylic acid). A discrete binuclear [2 + 2] metallomacrocycles cadmium(II) complex of 1 is 0D, 3 and 5 exhibit one-dimensional helical and zigzag chain structures, respectively. 4 Forms a 2D layer with sql net topology bridged by carboxylate anion and L2, while 2 is an overall 3D array with the diamond topology (dia). In these complexes, the influences of anions coordination on the framework formation were observed and discussed. These results indicate the spacer length of the ligands and anions play important roles in controlling the diversity structural topologies of such metal–organic coordination architectures. The thermogravimetric analyses, X-ray powder diffraction and solid-state luminescent properties of the complexes have also been investigated.

Three flexible α,ѡ-bis(5,6-dimethylbenzimidazolyl)alkane ligands with different spacers were reacted with CdX2 (X = Cl, Br, I) hydrothermally, resulting in three coordination architectures, namely [CdI2(L1)]n (1), [CdBr2(L2)]n (2), and Cd2Cl4(L3)2 (3) [L1 = 1,3-bis(5,6- dimethylbenzimidazole)propane, L2 = 1,5-bis(5,6-dimethylbenzimidazole)pentane, L3 = 1,6- bis(5,6-dimethylbenzimidazole)hexane]. They have been characterized by elemental analyses, IR spectra, thermogravimetric (TG) analysis, and single-crystal X-ray diffraction. Complex 1displays a helical chain linked by the ligands L1, and a 2D supramolecular network is constructed through π-π stacking interactions; complex 2shows a helical chain structure with connections through two kinds of strong π-π stacking interactions into an intricate 3D supramolecular network; complex 3 contains dinuclear metallomacrocycles. The fluorescence properties of 1-3have been investigated in the solid state

Three cadmium(II) coordination polymers, [CdBr2(L1)] n (1), [CdI2(L2)] n (2), and Cd2Br4(L3)2 (3), where L1 = 1,3-bis(5,6-dimethylbenzimidazole)propane, L2 = 1,4-bis(5,6-dimethylbenzimidazole)butane, and L3 = 1,6-bis(5,6-dimethylbenzimidazole)hexane, have been synthesized by hydrothermal methods and characterized by elemental analyses, IR spectra, TGA, PXRD, and X-ray crystallographic diffraction. Complex 1 contains a 1-D helical chain in which CdBr2 units are linked by L1. For 2, each CdI2 is connected by two different conformations of L2 to form a 1-D zigzag chain. For 3, each CdBr2 is linked by L3 bridges to afford a binuclear structure. These results indicate that the spacer length of the ligands play important roles in assembly of Cd(II) coordination polymers. Thermogravimetric analyses and solid-state luminescent properties of the complexes have also been investigated.

Compounds [CdLCl2] n (1) and {[Cd(L)2(ClO4)]·ClO4} n (2), where L = 1,3-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, have been synthesized by hydrothermal method, and characterized by element analysis, IR spectra, Powder XRD, and X-ray crystallographic diffraction. Cd(II) in 1 and 2 are both trigonal bipyramidal. Different cadmium salts of chloride and perchlorate lead to different configurations of [Cd2L2]2+, trans-form in 1 but trans and cis-forms in 2. The 1-D beaded chains of 1 are further linked to generate a 3-D supramolecular architecture by strong π–π stacking interactions as well as intermolecular C–H ··· Cl hydrogen bonds. In 2, the 1-D beaded chains are further assembled by intermolecular C–H ··· O hydrogen bonds to form a 2-D layer. Solid-state fluorescent properties of 1 and 2 were investigated at room temperature.

A new mononuclear complex Mn(bbbi)2(H2O)4(ClO4)2·(bbbi)2·(H2O)2 1 (bbbi = 1,4-bis(benzimidazol-1-yl)-2-butene) is synthesized under hydrothermal conditions and characterized by IR spectroscopy, elemental analysis, and single crystal X-ray structural analysis. Crystal data for 1: triclinic, $$P\bar 1$$ , a = 8.8478(7) A, b = 15.0550(11) A, c = 16.4310(12) A, α = 108.657(7)°, β = 104.044(7)°, Γ = 99.317(7)°, V = 1942.2(3) A3, Z = 1, final R = 0.0621. Each manganese atom is octahedrally coordinated by four aqua ligands and two nitrogen atoms of two distinct bbbi ligands. The molecule is stabilized by hydrogen bonding and π…π interactions.

A novel copper(II) complex {[Cu(BIX)2(H2O)2](PhCOO)2} n (1) (BIX = 1,4-bis(imidazole-1-methyl))-benzene) is synthesized and characterized by elemental analysis, IR, TG, and single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic crystal system with the P-1 space group, Z = 1, a = 9.465(2) A, b = 9.703(2) A, c = 12.060(2) A, α = 77.26(3)°, β = 70.37(3)°, γ = 67.14(3)°, and V = 956.1(3) A3. The crystal structural analysis of complex 1 shows that the copper center is six-coordinated in an elongated octahedral geometry by four N atoms from four different BIX and two O atoms from two water molecules; two neighboring Cu(II) cations are bridged by two BIX extending into an infinite 1D double chain structure.

Two novel zinc coordination polymers {[Zn(PhCOO)2(bmix)]}n 1 and {[Zn(ada)(bmix)]·(H2O)2}n 2 (bmix = 1,4-bis(2-methylimidazole-1-ylmethyl)benzene, H2ada = adipic acid), were obtained by the hydrothermal reactions of bmix and zinc acetate with two carboxylate anions, respectively. Structural analyses show that complex 1 possess a one-dimensional helix chain structure, 2 takes two-dimensional corrugated (4,4) layer motif. The structural differences of two complexes indicate that organic carboxylate anions play important roles in the formation of such zinc(II) coordination architectures.

A novel Cu(II) mixed-ligand complex, {[Cu(sq)(L)(H2O)]· 0.9H2O}n (1) (sq = squarate dianion, L = 5,5′-dimethyl-2,2′-bipyridine), has been synthesized and characterized by elemental analyses, infrared (IR), and X-ray single-crystal diffraction. In 1, each copper(II) ion has a five-coordinated environment with square pyramidal geometry. A one-dimensional (1D) chain structure of the complex is constructed by squarate in μ-1,2-bis(monodentate) coordination mode and further forms a two-dimensional (2D) framework via “metal chelate–metal chelate ring” π–π stacking interactions between the adjacent chains. This unexpected π–π stacking interaction provides structural evidence for the metalloaromaticity of the Cu(II)-(aromatic α,α′-diimines) chelate rings.

Two new cobalt(II) coordination polymers, namely [Co1.5(PhCOO)3(bbbm)1.5(H2O)] n (1) and [Co(chdc)(bbbm)] n (2) (bbbm = 1,1′-(1,4-butanediyl)bis-1H-benzimidazole, H2chdc = 1,4-cyclohexanedicarboxylic acid), have been synthesized and structurally characterized by single crystal X-ray diffraction. The cobalt(II) centers display different environments, with trigonal–bipyramidal and octahedral geometries in 1 and a tetrahedral geometry in 2. The 1D linear chains of complex 1 and ladder-like chains of complex 2 are bridged by bbbm in bis-monodentate coordination mode; the variation of the carboxylate co-ligand effectively tunes the resulting framework architecture. The degradation of methyl orange in a photochemical Fenton-like process using complexes 1 and 2 as catalysts was investigated.

Intense red phosphors, AgGd 1− x Eu x (W 1− y Mo y ) 2 O 8 ( x =0.0–1.0, y =0.0–1.0), have been synthesized through traditional solid-state reaction and characterized by X-ray diffraction (XRD) and photoluminescence (PL). XRD results reveal that AgGd 1− x Eu x W 2 O 8 synthesized at 1000 °C has a tetragonal crystal structure, which is named as high temperature phase (HTP) AgGdW 2 O 8 . All phosphors compositions with Eu 3+ show red and green emission on excitation either in the charge-transfer or Eu 3+ levels. Analysis of the emission spectra with different Eu 3+ concentrations reveal that the optimum dopant concentration for Eu 3+ is x =0.6 in the HTP AgGd 1− x Eu x W 2 O 8 ( x =0.0–1.0). Studies on the AgGd 0.4 Eu 0.6 (W 1− y Mo y ) 2 O 8 ( y =0.0–1.0) and AgGd 1− x Eu x (W 0.7 Mo 0.3 ) 2 O 8 ( x =0.0–1.0) show that the emission intensity is maximum for compositions with y =0.3 and x =0.5, respectively, and a decrease in emission intensity is observed for higher y or x values. The Mo 6+ and Eu 3+ co-doped AgGd(WO 4 ) 2 phosphors show higher emission intensity in comparison with the singly Eu 3+ -doped AgGd(WO 4 ) 2 in UV region. The intense emission of the tungstate/molybdate phosphors under 394 and 465 nm excitations, respectively, suggests that these materials are promising candidates as red-emitting phosphors for near-UV/blue GaN-based white LED for white light generation.

Three new complexes, [Ni2(dpc)2(L1)2(H2O)2] · 4H2O (1), [Ni(dpc)(L2)1.5] n (2), and {[Ni(dpc)(L3)1.5] · 2H2O} n (3), where H2dpc = dipicolinic acid, L1 = 1,4-bis(2-methylimidazol-1-yl)butane, L2 = 4,4′-bis(2-methylimidazol-1-ylmethyl)biphenyl, and L3 = 1,4-bis(benzimidazol-1-yl)-2-butylene, have been synthesized by hydrothermal methods and characterized by elemental analyses, infrared spectra, thermogravimetric analysis, and X-ray crystallography. The common structural characteristic of the three complexes is that the Ni2+ is coordinated by tridentate dipicolinate through nitrogen of pyridine and oxygen of carboxylate, serving as a terminal ligand. In 1, two L1 link two [Ni(dpc)(H2O)] units to a discrete binuclear metallomacrocycle with a 22-membered ring, which is assembled through multiple O–H ··· O hydrogen bonds to form a 3-D supramolecular framework. Complex 2 exhibits a 1-D ladder-like chain structure constructed by cis/trans-conformation L2 linking metal centers; 3 displays a 2-D (6,3) topology, be...

Ce doped yttrium aluminium garnet (YAG:Ce) was synthesized by LiF assisted sol–gel combustion method. The thermal behavior, composition, and microstructure feature of the precursor were studied by TG/DTA, XRD, PL, and SEM. The using of LiF in the sol–gel combustion process was helpful to decrease the sintering temperature about 200 °C. The X-ray diffraction patterns of the powder sintered at 540 °C were identical with the stoichiometric YAG composition, which was the lowest temperature reported for the synthesis of crystalline and single phase YAG. The PL intensity of the particles was found to be affected by the content of LiF and this phenomenon was thought to be related to the change of phase composition with the increase of flux.