Stable yellow light emission from lead-free copper halides single crystals for visible light communication

Yellow light-emitting diodes(LEDs) as soft light have attracted abundant attention in lithography room, museum and art gallery. However, the development of efficient yellow LEDs lags behind green and blue LEDs, and the available perovskites yellow LEDs suffer from the instability. Herein, a pressure-assisted cooling method is proposed to grow lead-free CsCu2I3single crystals, which possess uniform surface morphology and enhanced photoluminescence quantum yield(PLQY) stability, with only 10% PLQY losses after being stored in air after 5000 h.Then, the single crystals used for yellow LEDs without encapsulation exhibit a decent Correlated Color Temperature(CCT) of 4290 K, a Commission Internationale de l’Eclairage(CIE) coordinate of(0.38, 0.41), and an excellent 570-h operating stability under heating temperature of 100°C. Finally, the yellow LEDs facilitate the application in wireless visible light communication(VLC), which show a-3 dB bandwidth of 21.5 MHz and a high achievable data rate of 219.2 Mbps by using orthogonal frequency division multiplexing(OFDM) modulation with adaptive bit loading. The present work not only promotes the development of lead-free single crystals, but also inspires the potential of CsCu2I3in the field of yellow illumination and wireless VLC.

Synthesis,Structure and Luminescent Properties of Polymeric Copper(Ⅰ) Halide Complexes Bearing Phosphine and N-donor Bridging Ligands

Three polymeric copper（Ⅰ） halide complexes beating phosphine and N-donor bridging ligands, [（PPh3）2Cu2（μ-Br）2（μ-4,4＇-bipy）]∞ 1 （bipy = bipyridine）, [（PPh3）2Cu2（μ-Br）2（μ- bpe）]∞ 2 （bpe = trans-1,2-bis（4-pyridyl）ethene） and [（PPh3）2Cu2（μ-Cl）2（μ-bpe）]∞ 3, were synthesized by the multilayer diffusion method, and the structures were refined by single-crystal X-ray diffraction. Complex 1 crystallizes in triclinic, space group P1^- with a = 9.122（3）, b = 9.322（3）, c = 13.201（4） A, α = 106.440（4）, β= 105.965（5）, γ= 94.167（5）°, V = 1021.3（6） A^3, Mr= 967.62, Z = 1, De= 1.573 g/cm^3, F（000） = 486, μ = 3.111 mm^-1, the final R = 0.0383 and ωR = 0.0960 for 2792 observed reflections （I 〉 2σ（I））. Complex 2 crystallizes in triclinic, space group P1^- with a = 9.420（3）, b = 10.209（4）, c = 12.407（4） A, α = 104.136（6）, β = 108.132（5）, γ= 95.338（6）°, V = 1081.0（7） A^3, Mr= 496.83, Z = 2, Dc= 1.526 g/cm^3, F（000） = 500, μ = 2.941 mm^-1, the final R = 0.0445 and ωR = 0.1117 for 3251 observed reflections （I 〉 2σ（I））. Complex 3 crystallizes in triclinic, space group P1^- with a = 8.32（1）, b = 11.53（2）, c = 13.94（3） A, α = 109.57（3）, β= 93.85（3）, γ= 97.28（3）°, V= 1242（4） A^3, Mr= 1074.59, Z = 1, Dc = 1.436 g/cm^3, F（000） = 548, μ = 1.279 mm^-1, the final R = 0.0786 and ωR = 0.1586 for 2266 observed reflections （I 〉 2σ（I））. The complexes exhibit intensive solid-state photoluminescence tentatively assigned to an admixture of triplet intraligand （IL） and metal-to-ligand charge-transfer （MLCT） excited state.

Light-emitting diodes based on all-inorganic copper halide perovskite with self-trapped excitons

Light-emitting diodes based on lead halide perovskite have attracted great attention due to their outstanding performance.However,their application is plagued by the toxicity of Pb and the poor stability.Herein novel copper-based all inorganic perovskite CsCu2I3 with much enhanced stability has been reported with a potential photoluminescence quantum yield(PLQY)over 20%and self-trapped excitons(STE).By taking advantage of its extraordinary thermal stability,we successfully fabricate high-quality CsCu2I3 film through direct vacuum-based deposition(VBD)of CsCu2I3 powder.The resulting film shows almost the same PLQY with the synthesized powder,as well as excellent uniformity and stability.The perovskite light-emitting diodes(Pe-LED)based on the evaporated CsCu2I3 emitting layer achieve a luminescence of 10 cd/m2 and an external quantum efficiency(EQE)of 0.02%.To the best of our knowledge,this is the first CsCu2I3 Pe-LED fabricated by VBD with STE property,which offers a new avenue for lead-free Pe-LED.

PROPERTIES AND STRUCTURE OF COPPER-CADMIUM HALIDE PHOTOCHROMIC GLASSES

The photochromic properties of photochromic glasses containing both copper halides and cadmium halides depend mainly upon the body glass composi- tion. The composition range of glass matrix can be described by F=[(R_20+MO)-Al_20_3]/B_20_3·In this paper, the basic structure of the glasses is investigated in terms of IR and Raman spectroscopy in detail. The results demonstrate that the network of body glass is constructed by [SiO_4], [BO_3], [BO_4] and [Al0_4], in which [BO_3] and [BO_4] are interconnec- ted into two kinds of borate groups and a kind of boroxol ring. Finally, the relationships between structure and properties have been discussed on the scale of molecules and molecular groups.

Optimization of copper extraction for bioleaching of complex Cu-polymetallic concentrate by moderate thermophiles

Effects of initial pH, temperature, liquid volume, rotation speed, galvanic interaction （pyrite ratio） and pulp density on bioleaching of complex Cu-polymetallic concentrate were investigated. The results indicated that the copper extraction at pH 1.5 was 1.5 and 1.4 times that at pH 1.0 and pH 2.0 respectively. The copper extraction obtained at 45 ℃ was 1236.8%higher than that at 50 ℃. With the increase of rotation speed or the decrease of liquid volume, copper extraction was improved obviously. Copper extraction was improved gradually with the increase of pyrite ratio. However, when the ratio was higher than 20.0%, no further increase in copper extraction was observed. And the statistically significant interactive effects on copper extraction were found between temperature and pH, and temperature and pyrite ratio.

Catalytic epoxidation of olefin over supramolecular compounds of molybdenum oxide clusters and a copper complex

The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu（bipy）]4[Mo15O47].2H2O （1） and [Cu1（bix）][（Cu1bix） （δ-MoVl8O26）0.5] （2） （bipy = 4,4＇-bipyridine, bix = 1,4-bis（imidazole-1-ylmethyl）benzene）. Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide （t-BuOOH） as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates.

Effects of binuclear copper(Ⅱ)threonine complex on blood glucose, lipids and protection of the hearts and kidneys in diabetic mice

Aim To study the effects of binuclear copper （Ⅱ） threonine complex （Cu2 （Thr）4） as analogue of superoxide dismutase （SOD） on blood glucose, blood lipids and vessels of hearts and kidneys in diabetic mice. Methods Diabetic mouse model was established by intraperitioneal injection of alloxan. Low, middle, and high doses of Cu2（Thr）4 at 0.002%, 0.02% and 0.1% were given respectively to diabetic mice following lavage. The fasting blood glucose was determined after the diabetic mice were given Cu2 （Thr）4 for 0, 30, and 45 d. The diabetic mice were killed on the 45th day. Then glycosylated hemoglobin （HbAlc） and blood lipids were assayed, and pathologic changes in hearts and kidneys stained with HE were observed. Results Compared with the control group in which the diabetic mice were given distilled water, the value of blood glucose reduced significantly in middle dose group （P 〈 0.01 ）, followed by that in low dose group （P 〈 0.05）. TC level reduced markedly and HDL level increased significantly in all three treatment groups （P 〈 0.05）. Especially in middle dose group, cardiac muscle fibers were neatly arranged, nucleus and cytoplasm well distributed, glomeruli showing normal structure, cells well distributed and staining being normal. Conclusion Cu2 （Thr）4 reduces blood glucose, regulates blood lipids, and play protective action on the vessels of hearts and kidneys in diabetic mice. The effects of it in middle dose were better than those of other doses.

Indium-doped perovskite-related cesium copper halide scintillator films for high-performance X-ray imaging

Scintillators are widely utilized in high-energy radiation detection in view of their high light yield and short fluorescence decay time.However,constrained by their current shortcomings,such as complex fabrication procedures,high temperature,and difficulty in the large scale,it is difficult to meet the increasing demand for costeffective,flexible,and environment-friendly X-ray detection using traditional scintillators.Perovskite-related cesium copper halide scintillators have recently received multitudinous research due to their tunable emission wavelength,high photoluminescence quantum yield(PLQY),and excellent optical properties.Herein,we demonstrated a facile solution-synthesis route for indium-doped all-inorganic cesium copper iodide(Cs_(3)Cu_(2)I_(5))powders and a high scintillation yield flexible film utilizing indium-doped Cs_(3)Cu_(2)I_(5)powders.The large area flexible films achieved a PLQY as high as 90.2%by appropriately adjusting the indium doping concentration,much higher than the undoped one(73.9%).Moreover,benefiting from low self-absorption and high PLQY,the Cs_(3)Cu_(2)I_(5):In films exhibited ultralow detection limit of 56.2 n Gy/s,high spatial resolution up to 11.3 lp/mm,and marvelous relative light output with strong stability,facilitating that Cs_(3)Cu_(2)I_(5):In films are excellent candidates for X-ray medical radiography.Our work provides an effective strategy for developing environment-friendly,low-cost,and efficient scintillator films,showing great potential in the application of highperformance X-ray imaging.

Hydrothermal Synthesis,Crystal Structure and Thermal Stability of a Binuclear Copper(Ⅱ) Complex with 3-(Pyridin-2-yl)-1,2,4-triazole

One novel binuclear copper（Ⅱ） complex [Cu 2 （Hpt） 2 （CO 3） 2 （H 2 O） 2 ]·H 2 O with copper carbonate and 3-（pyridin-2-yl）-1,2,4-triazole （Hpt） was hydrothermally synthesized and characterized by IR and X-ray diffraction analysis.The complex crystallizes in triclinic,space group P2 1 /n with a=0.6862（1）,b=0.7805（1）,c=1.1983（2） nm,α=72.03（2）,β=107.72（3）,γ=75.28（2）o,V=0.5884 nm 3,D c=2.105 g/cm 3,Z=1,F（000）=357,GOOF=1.041,the final R=0.01859 and wR=0.04348.The whole molecule is composed of two cooper ions,two Hpt molecules,two carbonate and three water molecules,forming a binuclear structure.The crystal structure shows that the cooper ion is coordinated with three nitrogen atoms from two Hpt molecules,two oxygen atoms from one carbonic acid and one water molecule,forming a distorted square pyramidal geometry.The TG analysis result shows that the title complex is stable under 131.0 ℃.

Synthesis, Structure and Fluorescence of a Copper(II) Complex [Cu_2(bipy)_2(Hpht)_2Cl](Hpht)(bipy=2,2'-Bipyridine,H_2pht=o-Phthalic Acid)

The title complex [Cu2(bipy)2(Hpht)2Cl](Hpht) (bipy = 2,2?-bipyridine, H2pht = o-phthalic acid) has been synthesized in the NaOH aqueous solution of CuCl2, Gd(NO3)3, bipy and H2pht, and its crystal structure was determined by single-crystal X-ray diffraction method. It crys- tallizes in triclinic, space group P1, C44H31ClCu2N4O12, Mr = 970.26, a = 8.175(2), b = 16.254(4), c = 16.946(4) ?, α = 62.966(6), β = 84.833(8), γ = 84.348(8)°, V = 1993.4(8) ?3, Z = 2, Dc = 1.616 g/cm3, F(000) = 988 and μ = 1.207 mm-1. The final R = 0.0429 and wR = 0.0843 for 5682 observed reflections with I > 2σ(I). Each copper(II) atom displays a distorted square-pyramidal geometry with two nitrogen atoms of one chelate 2,2?-bipy molecule, two oxygen atoms from two different bridging carboxylate groups of Hpht- and one bridging chloride atom occupying the apical position. The two copper(II) atoms are connected by a μ2-Cl atom and two bridging Hpht- ligands in a syn-syn coordination mode to form an isolated dinuclear unit. The molecular structure is extended to a one-dimensional wavy chain through hydrogen bonds. The title complex exhibits blue fluorescent emission at 443 nm (λex = 372 nm) in the solid state at room temperature.

Hydrothermal Synthesis and Structure of a Copper(II) Complex, [Cu(4,4'bpy)(H_2O)_3]SO_42H_2O

The title complex [Cu(4,4?bpy)(H2O)3]SO42H2O (Mr = 405.86) was synthesized under hydrothermal conditions and its crystal structure has been determined by X-ray diffraction. It crystallizes in the hexagonal system, space group P61 with a = 11.1870(4), c = 21.578(1) ? V = 2338.6(2) ?, Dc = 1.729 g/cm3, Z = 6, m(MoKa) = 1.583 mm-1 and F(000) = 1254. The final R and wR are 0.0253 and 0.0416 for 1458 observed reflections with I≥2s(I), respectively. It was revealed that the square pyramidal Cu(II) sites are linked through 4,4?bipyridine groups, forming infinite one-dimensional chains, with the sulfate anions and lattice water molecules occupying the inter-chain positions. During the electrostatic interactions, there exist O…O hydrogen bonds and p-p stacking interactions between the parallel aromatic bipy rings in the structure.

Synthesis and Crystal Structure of a New Copper(II) Complex with 4-Cyanobenzoic Acid

A new Cu（Ⅱ） complex [Cu（4-cba）（1,10-phen）（H2O）2]（NO3） （4-Hcba = 4-cyanobenzoic acid） has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by single-crystal X-ray diffraction. Crystallographic data： C20H16CuN4O7, Mr= 487.91, triclinic, space group PI, a = 7.8420（2）, b = 9.1070（2）, c = 15.1140（6） A, a = 76.889（9）, β = 81.332（11）, γ = 74.844（ 11）°, V = 1009.89（5） A^3, Z = 2, Dc = 1.605 g/cm^3, F（000） = 498, μ = 1.134 mm^-1, the final R = 0.0379 and wR = 0.0865 for 2977 observed reflections with 1 〉 2σ（Ⅰ）. The Cu（Ⅱ） atom is coordinated by two terminal water molecules, one chelating 1,10-phen molecule and one monodentate 4-cba ligand to form a slightly distorted square pyramid. The title complex molecules are connected through hydrogen bonds and π-π stacking interactions to generate a 2D layered network. The thermogravimetric analysis of the title complex has also been discussed.

Synthesis, structure, DNA binding and cleavage activity of a new copper(II) complex of bispyridylpyrrolide

A copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b = 1.0931(4) nm, c =2.5319(8) nm, and V = 2.4951(15) nm3. The copper center is situated in a square planar geometry. The interaction of the copper(II)complex with calf thymus DNA(CT-DNA) was investigated by electronic absorption, circular dichroism(CD) and fluorescence spectra. It is proposed that the complex binds to CT-DNA through groove binding mode. Nuclease activity of the complex was also studied by gel electrophoresis method. The complex can efficiently cleave supercoiled p BR322 DNA in the presence of ascorbate(H2A) via oxidative pathway. The preliminary mechanism of DNA cleavage by the complex with different inhibiting reagents indicates that the hydroxyl radicals were involved as the active species in the DNA cleavage process.

Hydrothermal Synthesis,Crystal Structure and Electrochemical Properties of the Copper(II) Complex [Cu_4O_4(phen)_4(ClC_6H_4COO)_2(H_2O)_2]·(H_2O)_3

The title complex of copper（Ⅱ） with m-chlorobenzoic acid, 1,10-phenanthroline （phen） and copper perchlorate has been synthesized and characterized in the solvent mixture of water and methanol. Crystal data for this complex： triclinic, space group PI^-, a = 1.06853（12）, b = 1.30740（16）, c = 1.49546（17） nm, α= 101.791（2）,β = 103.413（2）, γ = 105.815（2）°, V= 1.8736（4） nm^3, Mr = 904.67, Dc = 1.604 g/cm^3, Z = 2,/7（000） = 924,μ = 1.34 mm^-1, GOOF = 1.049, the final R = 0.0324 and wR = 0.0797. The structure analysis shows that a chair-like structure [Cu4O4] is defined by three quadrilaterals shaped by four copper and four oxygen atoms, and every copper ion is coordinated by three oxygen atoms from three wate： molecules and two nitrogen atoms from one 1,10-phenanthroline molecule, giving a distorted square-pyramidal coordination geometry. The CV analysis results indicate that the electron transfer in the electrode reaction is quasi-reversible.

Rapid, Catalytic Hydrolysis of DNA by Copper(Ⅱ) Complexes

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Effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores

The effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores was carried out by phase analysis means of XRD, optical microscopy and SEM-EDS. The results indicated that at ambient temperature, the easily leached copper oxide minerals were completely dissolved, while the bonded copper minerals were insoluble. At lukewarm temperature of 40℃, it was mainly the dissolution of copper in isomorphism state. With increasing temperature to 60℃, the copper leaching rate in the adsorbed state was significantly accelerated. In addition, when the temperature increased to 80℃, the isomorphic copper was completely leached, leaving 11.2% adsorbed copper un-leached. However, the copper in feldspar-quartz-copper-iron colloid state was not dissolved throughout the leaching process. Overall, the leaching rates of copper in different copper minerals decreased in the order: malachite, pseudo-malachite > chrysocolla > copper-bearing chlorite > copper-bearing muscovite > copper-bearing biotite > copper-bearing limonite > feldspar-quartz-copper-iron colloid.

Synthesis and Crystal Structure of a Copper(II) Complex with 2,4-Dihydroxybenzylidene Benzoylhydrazone Ligand

A new copper（Ⅱ） complex with formula CuL（py）, where L^2- is the dianion of 2,4-dihydroxybenzylidene benzoylhydrazone, has been synthesized and characterized by IR spectra and single-crystal X-ray diffraction method. The crystal belongs to monoclinic, space group P2 1/c with a=0.9630（4）, b=1.4808（6）, c=1.2320（5） nm, β=104.969（6）°, V=1.6973（Ⅱ） nm^3, Z=4, Dc=1.553 g/cm^3,μ（MoKa）=1.311 mm^-1, F（000）=812, R=0.0694 and wR=0.1727 for 1511 observed reflections （I〉2σ（I））. The crystal structure analysis indicates that the copper（Ⅱ） ion lies in a distorted square-planar environment composed of two oxygen atoms, one nitrogen atom from the tridentate acylhydrazone Schiff base ligand L^2- and one nitrogen atom from the pyridine ligand. Two adjacent molecules are connected via weak Cu…O bonding interactions to form dimers, which are further linked to generate a two-dimensional layer structure via interdimeric hydrogen bonds.

Syntheses, Structures and Photoluminescence of the Cadmium(Ⅱ) and Copper(Ⅱ) Complexes Based on 4'-(4''-Pyridyl)-2,2':6',2''-terpyridine and 1,4-Benzenedicarboxylic Acid Ligands

Two new metal-organic complexes [Cd2（1,4-BDC）（4-pytyp）（H2O）4]·（1,4-BDC）（1） and [Cu2（1,4-BDC）（4-pytyp）2（H2O）2]·（1,4-BDC）·8H2O（2）（4-pytyp = 4＇-（4＇＇-pyridyl）-2,2＇：6＇,2＇＇-terpyridine, 1,4-H2 BDC = 1,4-benzenedicarboxylic acid） have been synthesized under hydrothermal conditions and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The scrutiny of single-crystal structure reveals that complex 1 forms to a 3D supramolecular network linked by π-π stacking interactions and hydrogen bonds. X-ray diffraction analysis reveals that complex 2 exhibits a 3D supramolecular network linked through complicated hydrogen bonds. The thermogravimetric analysis and photoluminescent properties of 1 and 2 are discussed in detail.