To achieve a new type of carbon-based quantum dots with unique photoluminescence PL a simple approach for fabrication of graphene quantum dots GQDs with oxygen-rich groups was developed via the hydrothermal reaction b...To achieve a new type of carbon-based quantum dots with unique photoluminescence PL a simple approach for fabrication of graphene quantum dots GQDs with oxygen-rich groups was developed via the hydrothermal reaction by using graphene oxides GOs as a precursor. Transmission electron microscope TEM and atomic force microscope AFM characterizations confirmed that the sizes and heights of GQDs were 5.02±0.92 nm and 0.6 nm respectively.A strong PL emission exhibited unique excitation wavelength dependent features.Also the carbene-like free zigzag edge sites were proposed to be the origin of the strong PL emission.The GQDs were demonstrated to be a superior probe for Fe3＋ detection in aqueous solution with a high sensitivity and feasibility due to the special coordinate interaction between Fe3＋and the phenolic hydroxyl group at GQDs.展开更多
Praseodymium doped lithium yttrium molybdate Li Y1-8x Pr x（Mo O4）2（x=0.005-0.025） phosphors were successfully prepared by the hydrothermal method. The phase, morphology, and luminescent property of the prepared ph...Praseodymium doped lithium yttrium molybdate Li Y1-8x Pr x（Mo O4）2（x=0.005-0.025） phosphors were successfully prepared by the hydrothermal method. The phase, morphology, and luminescent property of the prepared phosphors were investigated by X-ray diffraction and scanning electron microscopy. The results indicated that doping of Pr^3＋ ions did not change the main phase of the phosphors. The samples emitted red luminescence upon excitation at 453 nm and the strongest emission peak corresponding to the characteristic transition of the Pr3＋ ion： 3P0→3F2 was observed at 657 nm. Li Y（Mo O4）2：Pr^3＋ red phosphors could be effectively excited by blue light emitting-diodes to emit red light; thus, acting as potential candidates for compensating the red light deficiency of cerium doped yttrium aluminum garnet yellow phosphor.展开更多
The europium ions doped MMoO4 （M=Sr, Ba） nanophosphors were successfully synthesized via a facile hydrothermal method using isopropanol. The relationship between phosphor crystalline phase, morphology, photohtminesc...The europium ions doped MMoO4 （M=Sr, Ba） nanophosphors were successfully synthesized via a facile hydrothermal method using isopropanol. The relationship between phosphor crystalline phase, morphology, photohtminescent properties and hexadecyl trimethyl ammonium bromide （CTAB） concentration, pH value in precursor solution was investigated. The results indi- cated that the morphology and photoluminescent properties were strongly influenced by CTAB concentration and pH value in precursor solution. In SrMoO4：Eu3＋ hosts, the phosphor surface tended to become smoother as the concentration of CTAB was increased; while particles tended to agglomerate as increasing pH value. The relative intensity ratio of charge transfer band to Eu3＋ characteristic emission peaks of MMoO4：Eu3＋ （M=Sr, Ba） was changed as CTAB concentration and pH value changed. The emission spectra of MMoO4：Eu3＋ （M=Sr, Ba） could be adjusted by CTAB concentration and pH value due to their impacts on the structure. It was im- portant that the different morphologies and photoluminescent properties of MMoO4：Eu3＋ （M=Sr, Ba） could be obtained by the facile hydrothermal method and modulated by changing CTAB concentration and pH value.展开更多
Long afterglow photoluminescent materials Sr2MgSi2O7 doped with Eu2+, Dy3+ were prepared by sol-gel method. The synthesized samples were characterized by X-ray diffraction. The excitation spectrum, emission spectrum a...Long afterglow photoluminescent materials Sr2MgSi2O7 doped with Eu2+, Dy3+ were prepared by sol-gel method. The synthesized samples were characterized by X-ray diffraction. The excitation spectrum, emission spectrum and long decay curve were measured and analyzed. XRD pattern indicates that phosphor is with Sr2MgSi2O7 crystal structure. The wide range of excitation wavelength indicates that luminescent material can be excited by light from ultraviolet ray to visible light. The main peak of emission spectrum is located at 466 nm. Sample excited by visible light can emit bright blue light, and the afterglow time lasts more than 8 h.展开更多
A new complex,[Cd（L）2（pbda）]n（1,L = 3-（2-pyridyl）-4-（p-methoxyphenyl）-5-（2-thienyl）-1,2,4-triazole,H2pbda = 1,4-benzenedicarboxylic acid）,has been hydrothermally prepared and characterized by single-crysta...A new complex,[Cd（L）2（pbda）]n（1,L = 3-（2-pyridyl）-4-（p-methoxyphenyl）-5-（2-thienyl）-1,2,4-triazole,H2pbda = 1,4-benzenedicarboxylic acid）,has been hydrothermally prepared and characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental analysis and PXRD.The complex crystallizes in monoclinic,space group P21/c with a = 8.2929（9）,b = 21.668（2）,c = 10.9940（11） ,β = 90.242（2）o,V = 1975.5（4） 3,Z = 2,C44H32N8O6S2Cd,Mr = 945.30,Dc = 1.589 g/cm3,μ = 0.721 mm-1,S = 1.097,F（000） = 960,the final R = 0.0590 and wR = 0.1045 for 3846 observed reflections（I 2σ（I））.In the title complex,the rigid bridging pbda2-ligands utilize oxygen atoms of carboxylate groups to coordinate with Cd（II） atoms to form one-dimensional chains which are further interlinked into a three-dimension framework via the intermolecular weak interactions.Photoluminescence study revealed that complex 1 exhibits strong fluorescent emission band in the solid state at room temperature.展开更多
Static charges on optical ant-counterfeiting membranes may lead to materials structural changes,dust stain aggravation,and misreading of optical information.Incorporating conductive particles is a common way to transf...Static charges on optical ant-counterfeiting membranes may lead to materials structural changes,dust stain aggravation,and misreading of optical information.Incorporating conductive particles is a common way to transfer accumulative charges,but the key issue is how to achieve high dispersion and effective distribution of particles.According to the strategy of assembly-induced structural colors,cellulose nanocrystals(CNCS)were employed as a solid emulsifier to stabilize hydrophobic carbon nanoparticles(CNPs)in aqueous media;subsequently.by solvent evaporation-modulated co-assembly under a condition of 30°C and 20 RH%,the binary suspensions containing 2wt% CNC and CNPs with the equivalent concentration relative to CNC ranged from 1:40 to 1:10 were used to prepare antistatic composite membranes.Surface chemistry regulation of CNCs was applied to optimize the dispersiblity of CNPs and the orientation of assembled CNC arrays,and the hydrophilic CNCS were more favorable for dispersion and assembly of binary suspension systems.Meanwhile,one dimension carbon nanotube(CNT)and zero-dimension carbon black(CB)were found to show better dispersibility than two dimension graphene,which was verified by a semi-quantitative theoretical study.Moreover,the stable binary systems of CNT/CNC and CB/CNC were chosen for co-assembly as membranes,and the uniaxial orientation could be optimized as the fll-width of 9.8°at half maximum deviation angle while the surface resistivity could also drop down to 3.42 × 102 Qcmcm-1.The structural color character of such paper homology and antistatic integrated membranes contributes to optical information hiding and-reading,and shows great potential as optical mark recognition materials for electrostatic discharge protective packaging and anti.counterfeiting applications.展开更多
A new 3D Cd（II） coordination polymer, [Cd2L（phen）（HzO）]n （1, HaL = terphenyl- 2,2＇,4,4＇-tetracarboxylic acid, phen = 1,10-phenanthroline）, has been hydrothermally synthesized and characterized by single-crys...A new 3D Cd（II） coordination polymer, [Cd2L（phen）（HzO）]n （1, HaL = terphenyl- 2,2＇,4,4＇-tetracarboxylic acid, phen = 1,10-phenanthroline）, has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, elemental analysis, TGA and IR spectroscopy. Complex 1 crystallizes in the monoclinic system, space group P21/c with a = 8.196（2）, b = 18.348（5）, c = 19.036（5） A, β = 97.741（5）°, V= 2836.6（14） A3, Z = 4, Dc = 1.933 Mg.m-3, p = 1.565 mm1, F（000） = 1624, the final R = 0.0356 and wR = 0.0612 for 4990 observed reflections with 1 〉 2a（I）. Complex 1 has a 1D chain containing Cd4 structural units, which are linked by 2- and 2＇-carboxyl groups of L4- to result in a 3D framework. Additionally, the photoluminescent property of 1 was also studied in the solid state at room temperature.展开更多
A novel luminescent coordination compound Eu（TTA）3（DEDAF）（1, TTA = 1,1,1-trifluoro-3-（2-thenoyl）acetone, DEDAF = 9,9-diethyl-4,5-diazafluoren） has been synthesized and fully characterized by infrared spectrum,...A novel luminescent coordination compound Eu（TTA）3（DEDAF）（1, TTA = 1,1,1-trifluoro-3-（2-thenoyl）acetone, DEDAF = 9,9-diethyl-4,5-diazafluoren） has been synthesized and fully characterized by infrared spectrum, elemental analysis, UV-vis spectrum, etc. X-ray single-crystal diffraction analysis reveals that compound 1 shows a mononuclear structure with the europium atom in coordinating to one DAF and three TTA ligands. The mononuclear structure units are assembled into a 3-D polymer by hydrogen bonds and π-π interactions. Photoluminescent property of 1 was investigated in detail at room temperature. Complex 1 emits strong red luminescence. However, it could be quenched even by small amount of water. The fluorescence intensity at 614 nm decreases linearly with the water content increasing（vol% in acetonitrile） in the range of 0.025~0.2% under 278 nm excitation. Thermogravimetric analysis has also been studied, which demonstrates good thermal stability of 1.展开更多
A novel 3D coordination compound of K（H2TDA）（H20） （1） （H3TDA = 1H-1,2,3-triazole-4,5-dicarboxylic acid） has been prepared and characterized by IR spectroscopy, elemental analysis, ICP and single-crystal X-ray ...A novel 3D coordination compound of K（H2TDA）（H20） （1） （H3TDA = 1H-1,2,3-triazole-4,5-dicarboxylic acid） has been prepared and characterized by IR spectroscopy, elemental analysis, ICP and single-crystal X-ray diffraction. Compound 1 displays strong fluorescent emission at room temperature.展开更多
Two new 2D coordination polymers, [Zn（HL）（Hbpp）]n （1） mid [Cd（HL）（Hbpp）（H2O）]n （2） （H4L = 1,3-di（2,4-dicarboxyphenyl） benzene, bpp = 1,3-di（4-pyridyl）propane）, have been hydrothermally synthesized ...Two new 2D coordination polymers, [Zn（HL）（Hbpp）]n （1） mid [Cd（HL）（Hbpp）（H2O）]n （2） （H4L = 1,3-di（2,4-dicarboxyphenyl） benzene, bpp = 1,3-di（4-pyridyl）propane）, have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, elemental analysis, TGA and 1R spectroscopy. Complex 1 crystallizes in monoclinic, space group P21/n, with a = 13.1031（6）, b = 14.7315（7）, c = 15.0041（7） A, β = 91.202（1）°, V= 2895.6（2） A3, Dc = 1.532 g/cm3, Mr = 667.97, F（000） = 1376.0, μ = 0.909 mm-1, Z = 4, the final R = 0.0481 and wR = 0.1304 for 7027 observed reflections with 1 〉 2a（/）. Complex 2 also belongs to the monoclinic space group P2Jn, with a = 13.6326（4）, b = 14.6432（4）, c = 14.9395（5）A, β = 93.132（1）°, V= 2977.84（16） A3, D, = 1.613 g/cm3, ）14,. = 1445.98, F（000） = 733.0,/1 = 0.794 mm-1, Z = 2, the final R = 0.0283 and wR = 0.0784 for 7230 observed reflections with I 〉 2σ（I）. Both complexes 1 and 2 form 2D net structures, which are further linked to form 3D supramolecular net structures via intermolecular hydrogen bonds and aromatic π-π stacking interactions.展开更多
A novel binuclear Ag（I） complex [Ag2（C6H6NaO）2（C6H7N3O）2]·2CH3CN （1） was synthesized by the evaporation reaction of silver nitrate and （E）-1-（pyrazin-2-yl）ethanone oxime （HL）. The complex was charac...A novel binuclear Ag（I） complex [Ag2（C6H6NaO）2（C6H7N3O）2]·2CH3CN （1） was synthesized by the evaporation reaction of silver nitrate and （E）-1-（pyrazin-2-yl）ethanone oxime （HL）. The complex was characterized by elemental analysis, IR spectrum and X-ray single-crystal diffraction analysis. It crystallizes in the monoclinic space group C2/c with a = 22.7089（3）, b = 11.5443（7）, c = 16.1468（4）/A, β = 127.7150（10）°, V= 3348.6（2） A^3, Dc = 1.675 g/cm^3, Mr = 844.42, Z = 4, F（000） = 1696.0,μ = 1.226 mm^-1, the final R =0.0250 and wR = 0.070. The coordination around the silver（I） atom is a distorted trigonal-bipyramidal geometry involving one protonated pyrazinyl oxime ligand （HL）, one deprotonated oxime ligand （L^-） and one CH3CN solvate molecule in the asymmetric unit of complex 1.展开更多
Solvothermal reaction of manganese（II） salt with monosodium 2-sulfoterephthalate（2-NaH2stp） and two multi-pyridine N-containing auxiliary ligands results in the formation of two new complexes formulated with [Mn2...Solvothermal reaction of manganese（II） salt with monosodium 2-sulfoterephthalate（2-NaH2stp） and two multi-pyridine N-containing auxiliary ligands results in the formation of two new complexes formulated with [Mn2（Hstp）2（bpp）2（H2O）4]（1） and [Mn3（stp）2（tpy）3（H2O）]（H2O）5（2）（bpp = benz-2,3-pyrimidine-[2,3-f]-1,10-phenanthroline, tpy = 2,2＇：6＇,2＇＇-terpyridine）. X-ray diffraction structural analyses of two complexes reveal their structural diversity（0D and 1D） due to the difference of auxiliary ligands. 1 is a discrete structure, in which the Mn（Ⅱ） ion is hexa-coordinated with one stp, one bpp ligand and two water molecules. Complex 2 is a one-dimensional（1D） chain-like structure with three crystallographically independent Mn（Ⅱ） ions. The photoluminescent properties could be assigned to the π-π＊ transition of 2-sulfoterephthalate ligands.展开更多
The coordination polymer [Zn1.5（2,2？,4？？-tpt）（tpa）2]n （2,2？,4？？-tpt = 3,4-bis（2- pyridyl）-5-（4-pyridyl）-1,2,4-triazole, H2tpa = terephthalic acid） has been obtained by solution evaporation method and c...The coordination polymer [Zn1.5（2,2？,4？？-tpt）（tpa）2]n （2,2？,4？？-tpt = 3,4-bis（2- pyridyl）-5-（4-pyridyl）-1,2,4-triazole, H2tpa = terephthalic acid） has been obtained by solution evaporation method and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. The title compound crystallizes in the triclinic system, space group P , with a = 10.331（3）, b = 10.596（1）, c = 14.966（3） ？, β = 99.029（0）o, V = 1448.86（6） ？3, Z = 2, Dc = 1.668 g/cm3, μ = 1.320 mm-1, F（000） = 740, R = 0.0359 and wR = 0.0841 with I 〉 2σ（I））. In this polymer, the asymmetric unit contains two crystallographically independent Zn（II） ions in different coordination environments. Zn（1） ion is five-coordinated, forming a distorted tetragonal pyramidal geometry, while the Zn（2） ion is six-coordinated to get a distorted octahedral geometry. Each Zn（II） ion is linked by 2,2？,4？？-tpt and H2tpa ligands, forming an infinite 2D structure. The existence of O（8）–H（8）？？？O（2） hydrogen bonding interactions leads the 2D chains to generate a 3D structure. In addition, 1 shows strong photoluminescent emissions in the solid state at room temperature, so it can be used as potential optical materials.展开更多
There are growing interests on phosphor thin films owing to their potential application in high-resolution devices such as cathode ray tubes and flat panel display devices. The solution-based sol-gel method is one of ...There are growing interests on phosphor thin films owing to their potential application in high-resolution devices such as cathode ray tubes and flat panel display devices. The solution-based sol-gel method is one of the most important techniques for the synthesis of various functional coating films. Compounds with the apatite structure are very suitable host lattices for various luminescent ions. Ca2RE8（SiO4）6O2 （ RE=Y, Gd, La ） is a kind of ternary rare-earth-metal silicate with oxyapatite structure, which has been used as host material for the luminescence of various rare earth and mercury-like ions. In this article, Ca2Gd8（SiO4）6O2：Dy^3＋phosphor films were dip-coated on quartz glass substrates through the sol-gel process. X-ray diffraction （XRD）, atomic force microscopy （AFM）, photoluminescence （PL） spectra, as well as lifetimes were used to characterize the resulting films. AFM study revealed that the phosphor films consisted of homogeneous particles. The Dy^3＋ showed its characteristic emission in crystalline phosphor films, i.e., ^4F9/2-^6H15/2 and ^4F9/2-^6H13/2.展开更多
A new 2D Zn（II） coordination polymer,[Zn（btc）0.5（phen）]n（1,H4btc = biphenyl-3,3＇,5,5＇-tetracarboxylic acid,phen = 1,10-phenanthroline）,has been hydrothermally synthesized and characterized by single-crystal ...A new 2D Zn（II） coordination polymer,[Zn（btc）0.5（phen）]n（1,H4btc = biphenyl-3,3＇,5,5＇-tetracarboxylic acid,phen = 1,10-phenanthroline）,has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis,elemental analysis and IR spectro-scopy.Complex 1 crystallizes in the triclinic system,space group P1 with a = 7.6878（6）,b = 10.3453（8）,c = 10.9589（9） ,α = 113.3540（10）,β = 90.5460（10）,γ = 90.4280（10）°,V = 800.09（11） 3,Z = 2,Dc = 1.696 Mg.m-3,μ = 1.566 mm-1,F（000） = 414,the final R = 0.0359 and wR = 0.0778 for 2441 observed reflections with I 2σ（I）.Complex 1 has a 2D layered network containing dinuclear Zn（II） structural units.The 2D layers are further linked by the phen molecules through π-π stacking interactions into a 3D supramolecular framework.The photoluminescent property of 1 was also studied in the solid state at room temperature.展开更多
Two new d;metal-based metal-organic frameworks,{[Zn;（btc）;（bib）;（H;O）;]·2H;O};（1）and{[Cd;（btc）;（bib）;（H;O）;]·6H;O};（2）(btc=1,3,5-benzenetricarboxylate anion,bib=1,4-bis（1-imidazolyl）benzene...Two new d;metal-based metal-organic frameworks,{[Zn;（btc）;（bib）;（H;O）;]·2H;O};（1）and{[Cd;（btc）;（bib）;（H;O）;]·6H;O};（2）(btc=1,3,5-benzenetricarboxylate anion,bib=1,4-bis（1-imidazolyl）benzene)have been prepared under hydrothermal conditions by the reactions of d;metal oxides of ZnO and CdO with the aromatic polycarboxylic H;btc and the N-heterocyclic bib.The two products were characterized by single-crystal X-ray diffraction analysis,elemental analysis,thermogravimetric analysis（TGA）,and IR spectroscopy.Complexes 1 and 2 crystallize in monoclinic C2/c and triclinic P 1 space groups,respectively.1 shows a 3D framework,and the potential large voids of the 3D network lead to a 3-fold interpenetrating architecture.2 displays a 2D framework,and the adjacent 2D layers expand into a 3D supramulecular network via rich hydrogen bonds.Moreover,the luminescent properties of the two complexes are investigated in solid state.展开更多
ABSTRAC Two new complexes [Cd（2,4＇-bpdc）（DPPZ）]2n·n H2O（1） and [Zn（2,4＇-Hbpdc）2（DPPZ）]· H2O（DPPZ = dipyrido[3,2-a：2＇,3＇-c]phenazine, 2,4＇-H2bpdc = 2,4＇-biphenyldicarboxylic acid） have been...ABSTRAC Two new complexes [Cd（2,4＇-bpdc）（DPPZ）]2n·n H2O（1） and [Zn（2,4＇-Hbpdc）2（DPPZ）]· H2O（DPPZ = dipyrido[3,2-a：2＇,3＇-c]phenazine, 2,4＇-H2bpdc = 2,4＇-biphenyldicarboxylic acid） have been hydrothermally synthesized. The structure of complex 1 was determined by single-crystal X-ray diffraction diffraction and further characterized by elemental analysis, IR spectrum, powder X-ray diffraction（XRD） and single-crystal X-ray diffraction. Complex 1 has 1D chains, which are further connected by π-π stacking interactions of neighbouring chains, generating a steady 3D supramolecular structure. Complex 2 shows the isolated mononuclear units, which are further extended to a 2D supramolecular layered structure through π-π stacking interactions and hydrogen bonds. Furthermore, complexes 1 and 2 exhibit green photoluminescent properties at room temperature.展开更多
Five novel europium(Ⅲ)complexes with 2-[4-(dibutylamino)-2-hydroxybenzoyl]benzoic acid(DAHB)as primary ligand and bathophenanthroline(batho),2,2’-bipyridyl(bipy),5,6-dimethyl-1,10-phenanthroline(dmph),1,10-phenanthr...Five novel europium(Ⅲ)complexes with 2-[4-(dibutylamino)-2-hydroxybenzoyl]benzoic acid(DAHB)as primary ligand and bathophenanthroline(batho),2,2’-bipyridyl(bipy),5,6-dimethyl-1,10-phenanthroline(dmph),1,10-phenanthroline(phen)as ancillary ligands were syn-thesized via solution precipitation method.The structural formulae of synthesized complexes were speculated to be Eu(DABH)_(3)·2H_(2)O(C1),Eu(DABH)_(3)·batho(C2),Eu(DABH)_(3)·bipy(C3),Eu(DABH)_(3)·dmph(C4)and Eu(DABH)_(3)·phen(C5)by elemental analysis,infrared spectroscopy and proton nuclear magnetic resonance spec-troscopy(^(1)H-NMR).The photoluminescent properties and thermal stability of the complexes were investigated by photoluminescent spectroscopy and thermogravimetric analysis(TG-DTG),respectively.The Commission Inter-nationale de I’Eclairage(CIE)color coordinates,Judd–Ofelt intensity parameter(Ω_(2)),total quantum yield,intrinsic quantum efficiency and energy transfer dynamics of com-plexes were also explored.The excitation spectra of com-plexes are extended up to visible region.These complexes exhibit characteristic photoemission of Eu^(3+)metal ion with high color purity in red region attributed to efficient energy transfer from ligand to metal ion.The replacement of water molecules from coordination sphere of europium ion by ancillary ligands results in enhancement of luminescent properties of the C2–C5 complexes,indicating that ancillary ligands act as additional light harvesting centers in sensiti-zation phenomenon.The thermal studies show that these complexes are suitable for meeting the requirement of temperature for fabrication of OLEDs devices.展开更多
Highly efficient Sr2Si5N8：Eu^2＋red emitting phosphor was successfully synthesized by a cost-effective direct silicon nitrida-tion and gas-reduction method. The effects of synthesis parameters, including reaction tem...Highly efficient Sr2Si5N8：Eu^2＋red emitting phosphor was successfully synthesized by a cost-effective direct silicon nitrida-tion and gas-reduction method. The effects of synthesis parameters, including reaction temperature, heating rate and gas species, on the crystal structure and photoluminescence of the prepared phosphors were studied. Single-phase Sr2Si5N8：Eu^2＋phosphor was ob-tained at 1500℃ with a heating rate of 300℃/h under NH3-1 vol.%CH4 atmosphere using starting silicon and oxide powders. Silicon powder and high heating rate favored the achievement of the pure Sr2Si5N8 phase. Under near-UV to blue light excitation, the obtained Sr2Si5N8：Eu2＋phosphor showed a board red emission band centered at about 625 nm, which agreed well with the phosphors prepared by the conventional solid-state reaction. The possible reaction mechanism was also proposed based on the experimental observations.展开更多
In this paper, the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ^1H NMR and ESI-MS. The duplex emits strong...In this paper, the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ^1H NMR and ESI-MS. The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state, respectively, and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference. In concentration of 〉40 mmol/L, the duplex can gelate DMSO, and the organogel formed shows good pure blue photoluminescence too. This novel duplex, for its well-defined structure and efficient photoluminescence property, is a prospective candidate for pure blue electroluminescent emitter.展开更多
基金The National Basic Research Program of China(973Program)(No.2013CB932902)the National Natural Science Foundation of China(No.21201034,21173042)the Fundamental Research Funds for the Central Universities(No.3207044403)
文摘To achieve a new type of carbon-based quantum dots with unique photoluminescence PL a simple approach for fabrication of graphene quantum dots GQDs with oxygen-rich groups was developed via the hydrothermal reaction by using graphene oxides GOs as a precursor. Transmission electron microscope TEM and atomic force microscope AFM characterizations confirmed that the sizes and heights of GQDs were 5.02±0.92 nm and 0.6 nm respectively.A strong PL emission exhibited unique excitation wavelength dependent features.Also the carbene-like free zigzag edge sites were proposed to be the origin of the strong PL emission.The GQDs were demonstrated to be a superior probe for Fe3＋ detection in aqueous solution with a high sensitivity and feasibility due to the special coordinate interaction between Fe3＋and the phenolic hydroxyl group at GQDs.
基金supported by National Natural Science Foundation of China(21205092)the National High-tech Research and Development Program of China(863 Program)(2011AA05A202)
文摘Praseodymium doped lithium yttrium molybdate Li Y1-8x Pr x（Mo O4）2（x=0.005-0.025） phosphors were successfully prepared by the hydrothermal method. The phase, morphology, and luminescent property of the prepared phosphors were investigated by X-ray diffraction and scanning electron microscopy. The results indicated that doping of Pr^3＋ ions did not change the main phase of the phosphors. The samples emitted red luminescence upon excitation at 453 nm and the strongest emission peak corresponding to the characteristic transition of the Pr3＋ ion： 3P0→3F2 was observed at 657 nm. Li Y（Mo O4）2：Pr^3＋ red phosphors could be effectively excited by blue light emitting-diodes to emit red light; thus, acting as potential candidates for compensating the red light deficiency of cerium doped yttrium aluminum garnet yellow phosphor.
基金Project supported by the Nation Natural Science Foundation of China(51562025)Graduate Student Innovation Special Funds(YC2016-S085)
文摘The europium ions doped MMoO4 （M=Sr, Ba） nanophosphors were successfully synthesized via a facile hydrothermal method using isopropanol. The relationship between phosphor crystalline phase, morphology, photohtminescent properties and hexadecyl trimethyl ammonium bromide （CTAB） concentration, pH value in precursor solution was investigated. The results indi- cated that the morphology and photoluminescent properties were strongly influenced by CTAB concentration and pH value in precursor solution. In SrMoO4：Eu3＋ hosts, the phosphor surface tended to become smoother as the concentration of CTAB was increased; while particles tended to agglomerate as increasing pH value. The relative intensity ratio of charge transfer band to Eu3＋ characteristic emission peaks of MMoO4：Eu3＋ （M=Sr, Ba） was changed as CTAB concentration and pH value changed. The emission spectra of MMoO4：Eu3＋ （M=Sr, Ba） could be adjusted by CTAB concentration and pH value due to their impacts on the structure. It was im- portant that the different morphologies and photoluminescent properties of MMoO4：Eu3＋ （M=Sr, Ba） could be obtained by the facile hydrothermal method and modulated by changing CTAB concentration and pH value.
文摘Long afterglow photoluminescent materials Sr2MgSi2O7 doped with Eu2+, Dy3+ were prepared by sol-gel method. The synthesized samples were characterized by X-ray diffraction. The excitation spectrum, emission spectrum and long decay curve were measured and analyzed. XRD pattern indicates that phosphor is with Sr2MgSi2O7 crystal structure. The wide range of excitation wavelength indicates that luminescent material can be excited by light from ultraviolet ray to visible light. The main peak of emission spectrum is located at 466 nm. Sample excited by visible light can emit bright blue light, and the afterglow time lasts more than 8 h.
基金supported by the National Natural Science Foundation of China (No. 21171040)the Natural Science Foundation of Anhui Provincial Education Commission (No. KJ2011B296 and KJ2009A047ZC)
文摘A new complex,[Cd（L）2（pbda）]n（1,L = 3-（2-pyridyl）-4-（p-methoxyphenyl）-5-（2-thienyl）-1,2,4-triazole,H2pbda = 1,4-benzenedicarboxylic acid）,has been hydrothermally prepared and characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental analysis and PXRD.The complex crystallizes in monoclinic,space group P21/c with a = 8.2929（9）,b = 21.668（2）,c = 10.9940（11） ,β = 90.242（2）o,V = 1975.5（4） 3,Z = 2,C44H32N8O6S2Cd,Mr = 945.30,Dc = 1.589 g/cm3,μ = 0.721 mm-1,S = 1.097,F（000） = 960,the final R = 0.0590 and wR = 0.1045 for 3846 observed reflections（I 2σ（I））.In the title complex,the rigid bridging pbda2-ligands utilize oxygen atoms of carboxylate groups to coordinate with Cd（II） atoms to form one-dimensional chains which are further interlinked into a three-dimension framework via the intermolecular weak interactions.Photoluminescence study revealed that complex 1 exhibits strong fluorescent emission band in the solid state at room temperature.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51973175 and 51603171)the Project for Chongqing University Innovation Research Group(No.CXQT19008)+1 种基金the Chongqing Talent Plan for Innovation and Entrepreneurship Demonstration Team(No.CQYC201903243)the Key Laboratory of Polymeric Composite&Functional Materials of Ministry of Education(No.PCFM201605).
文摘Static charges on optical ant-counterfeiting membranes may lead to materials structural changes,dust stain aggravation,and misreading of optical information.Incorporating conductive particles is a common way to transfer accumulative charges,but the key issue is how to achieve high dispersion and effective distribution of particles.According to the strategy of assembly-induced structural colors,cellulose nanocrystals(CNCS)were employed as a solid emulsifier to stabilize hydrophobic carbon nanoparticles(CNPs)in aqueous media;subsequently.by solvent evaporation-modulated co-assembly under a condition of 30°C and 20 RH%,the binary suspensions containing 2wt% CNC and CNPs with the equivalent concentration relative to CNC ranged from 1:40 to 1:10 were used to prepare antistatic composite membranes.Surface chemistry regulation of CNCs was applied to optimize the dispersiblity of CNPs and the orientation of assembled CNC arrays,and the hydrophilic CNCS were more favorable for dispersion and assembly of binary suspension systems.Meanwhile,one dimension carbon nanotube(CNT)and zero-dimension carbon black(CB)were found to show better dispersibility than two dimension graphene,which was verified by a semi-quantitative theoretical study.Moreover,the stable binary systems of CNT/CNC and CB/CNC were chosen for co-assembly as membranes,and the uniaxial orientation could be optimized as the fll-width of 9.8°at half maximum deviation angle while the surface resistivity could also drop down to 3.42 × 102 Qcmcm-1.The structural color character of such paper homology and antistatic integrated membranes contributes to optical information hiding and-reading,and shows great potential as optical mark recognition materials for electrostatic discharge protective packaging and anti.counterfeiting applications.
基金supported by the National Natural Science Foundation of China (21103146)the Natural Scientific Foundation of Shaanxi Province (2012JM2015)the Natural Scientific Research Foundation of Shaanxi Provincial Education Office (11JK0567)
文摘A new 3D Cd（II） coordination polymer, [Cd2L（phen）（HzO）]n （1, HaL = terphenyl- 2,2＇,4,4＇-tetracarboxylic acid, phen = 1,10-phenanthroline）, has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, elemental analysis, TGA and IR spectroscopy. Complex 1 crystallizes in the monoclinic system, space group P21/c with a = 8.196（2）, b = 18.348（5）, c = 19.036（5） A, β = 97.741（5）°, V= 2836.6（14） A3, Z = 4, Dc = 1.933 Mg.m-3, p = 1.565 mm1, F（000） = 1624, the final R = 0.0356 and wR = 0.0612 for 4990 observed reflections with 1 〉 2a（I）. Complex 1 has a 1D chain containing Cd4 structural units, which are linked by 2- and 2＇-carboxyl groups of L4- to result in a 3D framework. Additionally, the photoluminescent property of 1 was also studied in the solid state at room temperature.
基金supported by the Natural Science Foundation of Zhejiang Province(No.LY16B030009)National Natural Science Foundation of China(No.61205184)521 Talent Cultivation of Zhejiang Sci-Tech University(521 talent project of ZSTU)
文摘A novel luminescent coordination compound Eu（TTA）3（DEDAF）（1, TTA = 1,1,1-trifluoro-3-（2-thenoyl）acetone, DEDAF = 9,9-diethyl-4,5-diazafluoren） has been synthesized and fully characterized by infrared spectrum, elemental analysis, UV-vis spectrum, etc. X-ray single-crystal diffraction analysis reveals that compound 1 shows a mononuclear structure with the europium atom in coordinating to one DAF and three TTA ligands. The mononuclear structure units are assembled into a 3-D polymer by hydrogen bonds and π-π interactions. Photoluminescent property of 1 was investigated in detail at room temperature. Complex 1 emits strong red luminescence. However, it could be quenched even by small amount of water. The fluorescence intensity at 614 nm decreases linearly with the water content increasing（vol% in acetonitrile） in the range of 0.025~0.2% under 278 nm excitation. Thermogravimetric analysis has also been studied, which demonstrates good thermal stability of 1.
文摘A novel 3D coordination compound of K（H2TDA）（H20） （1） （H3TDA = 1H-1,2,3-triazole-4,5-dicarboxylic acid） has been prepared and characterized by IR spectroscopy, elemental analysis, ICP and single-crystal X-ray diffraction. Compound 1 displays strong fluorescent emission at room temperature.
基金Supported by the National Natural Science Foundation of China(No.21373178)the Open Foundation of Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education(338080043)the Natural Scientific Research Foundation of Shaanxi Provincial Education Office of China(No.13JS124)
文摘Two new 2D coordination polymers, [Zn（HL）（Hbpp）]n （1） mid [Cd（HL）（Hbpp）（H2O）]n （2） （H4L = 1,3-di（2,4-dicarboxyphenyl） benzene, bpp = 1,3-di（4-pyridyl）propane）, have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, elemental analysis, TGA and 1R spectroscopy. Complex 1 crystallizes in monoclinic, space group P21/n, with a = 13.1031（6）, b = 14.7315（7）, c = 15.0041（7） A, β = 91.202（1）°, V= 2895.6（2） A3, Dc = 1.532 g/cm3, Mr = 667.97, F（000） = 1376.0, μ = 0.909 mm-1, Z = 4, the final R = 0.0481 and wR = 0.1304 for 7027 observed reflections with 1 〉 2a（/）. Complex 2 also belongs to the monoclinic space group P2Jn, with a = 13.6326（4）, b = 14.6432（4）, c = 14.9395（5）A, β = 93.132（1）°, V= 2977.84（16） A3, D, = 1.613 g/cm3, ）14,. = 1445.98, F（000） = 733.0,/1 = 0.794 mm-1, Z = 2, the final R = 0.0283 and wR = 0.0784 for 7230 observed reflections with I 〉 2σ（I）. Both complexes 1 and 2 form 2D net structures, which are further linked to form 3D supramolecular net structures via intermolecular hydrogen bonds and aromatic π-π stacking interactions.
基金supported by the National Natural Science Foundation of China (20871099)the Natural Science Foundation of Gansu Province (0710RJZA113)
文摘A novel binuclear Ag（I） complex [Ag2（C6H6NaO）2（C6H7N3O）2]·2CH3CN （1） was synthesized by the evaporation reaction of silver nitrate and （E）-1-（pyrazin-2-yl）ethanone oxime （HL）. The complex was characterized by elemental analysis, IR spectrum and X-ray single-crystal diffraction analysis. It crystallizes in the monoclinic space group C2/c with a = 22.7089（3）, b = 11.5443（7）, c = 16.1468（4）/A, β = 127.7150（10）°, V= 3348.6（2） A^3, Dc = 1.675 g/cm^3, Mr = 844.42, Z = 4, F（000） = 1696.0,μ = 1.226 mm^-1, the final R =0.0250 and wR = 0.070. The coordination around the silver（I） atom is a distorted trigonal-bipyramidal geometry involving one protonated pyrazinyl oxime ligand （HL）, one deprotonated oxime ligand （L^-） and one CH3CN solvate molecule in the asymmetric unit of complex 1.
基金supported by the Postdoctoral Science Foundation of China(No.2014M562403)National Natural Science Foundation of China(No.21573189)
文摘Solvothermal reaction of manganese（II） salt with monosodium 2-sulfoterephthalate（2-NaH2stp） and two multi-pyridine N-containing auxiliary ligands results in the formation of two new complexes formulated with [Mn2（Hstp）2（bpp）2（H2O）4]（1） and [Mn3（stp）2（tpy）3（H2O）]（H2O）5（2）（bpp = benz-2,3-pyrimidine-[2,3-f]-1,10-phenanthroline, tpy = 2,2＇：6＇,2＇＇-terpyridine）. X-ray diffraction structural analyses of two complexes reveal their structural diversity（0D and 1D） due to the difference of auxiliary ligands. 1 is a discrete structure, in which the Mn（Ⅱ） ion is hexa-coordinated with one stp, one bpp ligand and two water molecules. Complex 2 is a one-dimensional（1D） chain-like structure with three crystallographically independent Mn（Ⅱ） ions. The photoluminescent properties could be assigned to the π-π＊ transition of 2-sulfoterephthalate ligands.
基金Supported by the Natural Science Foundation of Ningxia(No.NZ15006)the Research Project of Ningxia Colleges and Universities(No.NGY2017004)
文摘The coordination polymer [Zn1.5（2,2？,4？？-tpt）（tpa）2]n （2,2？,4？？-tpt = 3,4-bis（2- pyridyl）-5-（4-pyridyl）-1,2,4-triazole, H2tpa = terephthalic acid） has been obtained by solution evaporation method and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. The title compound crystallizes in the triclinic system, space group P , with a = 10.331（3）, b = 10.596（1）, c = 14.966（3） ？, β = 99.029（0）o, V = 1448.86（6） ？3, Z = 2, Dc = 1.668 g/cm3, μ = 1.320 mm-1, F（000） = 740, R = 0.0359 and wR = 0.0841 with I 〉 2σ（I））. In this polymer, the asymmetric unit contains two crystallographically independent Zn（II） ions in different coordination environments. Zn（1） ion is five-coordinated, forming a distorted tetragonal pyramidal geometry, while the Zn（2） ion is six-coordinated to get a distorted octahedral geometry. Each Zn（II） ion is linked by 2,2？,4？？-tpt and H2tpa ligands, forming an infinite 2D structure. The existence of O（8）–H（8）？？？O（2） hydrogen bonding interactions leads the 2D chains to generate a 3D structure. In addition, 1 shows strong photoluminescent emissions in the solid state at room temperature, so it can be used as potential optical materials.
基金supported by the Guidance Plan of Science and Technology Research and Development of Hebei Province (2005-2007)
文摘There are growing interests on phosphor thin films owing to their potential application in high-resolution devices such as cathode ray tubes and flat panel display devices. The solution-based sol-gel method is one of the most important techniques for the synthesis of various functional coating films. Compounds with the apatite structure are very suitable host lattices for various luminescent ions. Ca2RE8（SiO4）6O2 （ RE=Y, Gd, La ） is a kind of ternary rare-earth-metal silicate with oxyapatite structure, which has been used as host material for the luminescence of various rare earth and mercury-like ions. In this article, Ca2Gd8（SiO4）6O2：Dy^3＋phosphor films were dip-coated on quartz glass substrates through the sol-gel process. X-ray diffraction （XRD）, atomic force microscopy （AFM）, photoluminescence （PL） spectra, as well as lifetimes were used to characterize the resulting films. AFM study revealed that the phosphor films consisted of homogeneous particles. The Dy^3＋ showed its characteristic emission in crystalline phosphor films, i.e., ^4F9/2-^6H15/2 and ^4F9/2-^6H13/2.
基金supported by the Natural Scientific Research Foundation of Shaanxi Provincial Education Office of China (No. 11JK0572)
文摘A new 2D Zn（II） coordination polymer,[Zn（btc）0.5（phen）]n（1,H4btc = biphenyl-3,3＇,5,5＇-tetracarboxylic acid,phen = 1,10-phenanthroline）,has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis,elemental analysis and IR spectro-scopy.Complex 1 crystallizes in the triclinic system,space group P1 with a = 7.6878（6）,b = 10.3453（8）,c = 10.9589（9） ,α = 113.3540（10）,β = 90.5460（10）,γ = 90.4280（10）°,V = 800.09（11） 3,Z = 2,Dc = 1.696 Mg.m-3,μ = 1.566 mm-1,F（000） = 414,the final R = 0.0359 and wR = 0.0778 for 2441 observed reflections with I 2σ（I）.Complex 1 has a 2D layered network containing dinuclear Zn（II） structural units.The 2D layers are further linked by the phen molecules through π-π stacking interactions into a 3D supramolecular framework.The photoluminescent property of 1 was also studied in the solid state at room temperature.
基金Supported by the National Natural Science Foundation of China(No.21373178,21663031 and 21503183)the Scientific Research Foundation of Shaanxi Provincial Education Department(No.16JK1857)the Natural Scientific Research Foundation of Yan’an City Technology Division of China(No.2016kg-01)
文摘Two new d;metal-based metal-organic frameworks,{[Zn;（btc）;（bib）;（H;O）;]·2H;O};（1）and{[Cd;（btc）;（bib）;（H;O）;]·6H;O};（2）(btc=1,3,5-benzenetricarboxylate anion,bib=1,4-bis（1-imidazolyl）benzene)have been prepared under hydrothermal conditions by the reactions of d;metal oxides of ZnO and CdO with the aromatic polycarboxylic H;btc and the N-heterocyclic bib.The two products were characterized by single-crystal X-ray diffraction analysis,elemental analysis,thermogravimetric analysis（TGA）,and IR spectroscopy.Complexes 1 and 2 crystallize in monoclinic C2/c and triclinic P 1 space groups,respectively.1 shows a 3D framework,and the potential large voids of the 3D network lead to a 3-fold interpenetrating architecture.2 displays a 2D framework,and the adjacent 2D layers expand into a 3D supramulecular network via rich hydrogen bonds.Moreover,the luminescent properties of the two complexes are investigated in solid state.
基金Supported by the Program for NNSFC(21407064,21576112)NSF of Jilin Province(20130521019JH)the Science and Technology Development Plan of Siping City(2014052,2015049)
文摘ABSTRAC Two new complexes [Cd（2,4＇-bpdc）（DPPZ）]2n·n H2O（1） and [Zn（2,4＇-Hbpdc）2（DPPZ）]· H2O（DPPZ = dipyrido[3,2-a：2＇,3＇-c]phenazine, 2,4＇-H2bpdc = 2,4＇-biphenyldicarboxylic acid） have been hydrothermally synthesized. The structure of complex 1 was determined by single-crystal X-ray diffraction diffraction and further characterized by elemental analysis, IR spectrum, powder X-ray diffraction（XRD） and single-crystal X-ray diffraction. Complex 1 has 1D chains, which are further connected by π-π stacking interactions of neighbouring chains, generating a steady 3D supramolecular structure. Complex 2 shows the isolated mononuclear units, which are further extended to a 2D supramolecular layered structure through π-π stacking interactions and hydrogen bonds. Furthermore, complexes 1 and 2 exhibit green photoluminescent properties at room temperature.
基金the Junior Research Fellowship(JRF)from University Grants Commission,New Delhi,India(No.2061410096)。
文摘Five novel europium(Ⅲ)complexes with 2-[4-(dibutylamino)-2-hydroxybenzoyl]benzoic acid(DAHB)as primary ligand and bathophenanthroline(batho),2,2’-bipyridyl(bipy),5,6-dimethyl-1,10-phenanthroline(dmph),1,10-phenanthroline(phen)as ancillary ligands were syn-thesized via solution precipitation method.The structural formulae of synthesized complexes were speculated to be Eu(DABH)_(3)·2H_(2)O(C1),Eu(DABH)_(3)·batho(C2),Eu(DABH)_(3)·bipy(C3),Eu(DABH)_(3)·dmph(C4)and Eu(DABH)_(3)·phen(C5)by elemental analysis,infrared spectroscopy and proton nuclear magnetic resonance spec-troscopy(^(1)H-NMR).The photoluminescent properties and thermal stability of the complexes were investigated by photoluminescent spectroscopy and thermogravimetric analysis(TG-DTG),respectively.The Commission Inter-nationale de I’Eclairage(CIE)color coordinates,Judd–Ofelt intensity parameter(Ω_(2)),total quantum yield,intrinsic quantum efficiency and energy transfer dynamics of com-plexes were also explored.The excitation spectra of com-plexes are extended up to visible region.These complexes exhibit characteristic photoemission of Eu^(3+)metal ion with high color purity in red region attributed to efficient energy transfer from ligand to metal ion.The replacement of water molecules from coordination sphere of europium ion by ancillary ligands results in enhancement of luminescent properties of the C2–C5 complexes,indicating that ancillary ligands act as additional light harvesting centers in sensiti-zation phenomenon.The thermal studies show that these complexes are suitable for meeting the requirement of temperature for fabrication of OLEDs devices.
基金supported by National Natural Science Foundation of China(5107219111179037)+2 种基金University of Science and Technolgy of China-National Synchrotron Radiation Laboratory(USTC-NSRL)joint funds(KY2060140005)Anhui Provincial Natural Science Foundation(11040606M11)Anhui Provincial Education Department(KJ2012A289)
文摘Highly efficient Sr2Si5N8：Eu^2＋red emitting phosphor was successfully synthesized by a cost-effective direct silicon nitrida-tion and gas-reduction method. The effects of synthesis parameters, including reaction temperature, heating rate and gas species, on the crystal structure and photoluminescence of the prepared phosphors were studied. Single-phase Sr2Si5N8：Eu^2＋phosphor was ob-tained at 1500℃ with a heating rate of 300℃/h under NH3-1 vol.%CH4 atmosphere using starting silicon and oxide powders. Silicon powder and high heating rate favored the achievement of the pure Sr2Si5N8 phase. Under near-UV to blue light excitation, the obtained Sr2Si5N8：Eu2＋phosphor showed a board red emission band centered at about 625 nm, which agreed well with the phosphors prepared by the conventional solid-state reaction. The possible reaction mechanism was also proposed based on the experimental observations.
基金supported by the Foundation of Science and Technology Bureau,Sichuan Province(No. 2006j13-141)the National Natural Science Foundation of China(No.20672076).
文摘In this paper, the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ^1H NMR and ESI-MS. The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state, respectively, and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference. In concentration of 〉40 mmol/L, the duplex can gelate DMSO, and the organogel formed shows good pure blue photoluminescence too. This novel duplex, for its well-defined structure and efficient photoluminescence property, is a prospective candidate for pure blue electroluminescent emitter.
