Syntheses, Structures and Fluorescent Properties of Two 1D Chain Organic Amines and Metal Iodine Organic-inorganic Hybrid Compounds

Two bifunctional amines, 4-(2-aminoethyl)morpholine and histamine, were heated with PbI_2 and BiI_3 in concentrated HI aqueous solution to give one-dimensional(1D) organicinorganic hybrid compounds [(C_6H_(16)N_2O)PbI4]n(1) and [(C_(16)H_(20)N_(20))Bi_2I_(10)](2), respectively. In 1, the [PbI6] octahedra formed double chain anions through sharing-corner and-edge, and the protonated(C_6H_(16)N_2O)^(2+) cations were located at the vicinity of the double chains by hydrogen bonds. In 2, the [BiI_6] octahedra firstly formed dimeric [Bi_2I_(10)]^(4-) anion through sharing edge, and subsequently, the protonated histamine cations worked as bridge to link alternately with [Bi_2I_(10)]^(4-) anion by hydrogen bonds to form organic-inorganic hybrid 1D chains. In addition, compound 1 emitted a green light at the excitation wavelength of 400 nm and the maximum emission wavelength is at 503 nm.

Ultrasensitive detection of methamphetamine by antibody-modified transistor assay

Effective detection of methamphetamine(Met)requires a fast,sensitive,and cheap testing assay.However,commercially available methods require expensive instruments and highly trained operators,which are time-consuming and labor-intensive.Herein,an antibody-modified graphene transistor assay is developed for sensitive and minute-level detection of Met in complex environments.The anti-Met probe captured charged targets within 120 s,leading to a p-doping effect near the graphene channel.The limit of detection reaches 50 aM(5.0×10^(-17)M)Met in solution.The graphene transistor would be a valuable tool for Met detection effective prevention of drug abuse.

Thermoelectric Performance of Poly（3,4-ethylenedioxythiophene）：Poly（styrenesulfonate）

Thermoelectric （TE） performances are systematically investigated for the pellets of poly（3,4-ethylenedioxythiophene）：poly（styrenesulfonate） （PEDOT：PSS） with different organic additives and heating process as organic TE materials. The electrical conductivity, Seebeck coefficient and thermal conductivity versus temperature are determined, respectively. It is found that there is no distinct change for the Seebeck coefficient among each sample with the additions of dimethyl sulfoxide and ethylene glycol. The thermal conductivity measured in a wide range of temperature indicates that the PEDOT：PSS pellet have an extremely low value. The highest figure of merit （ZT = 1.75×10^-3） is observed at 270K among the PEDOT：PSS pellets.

Synthesis and Crystal Structure of 1-(2-Methyl-5-formyl-3-thienyl)-2-(2-methoxylphenyl)perfluorocyclopentene

A new family of photochromic diarylethene compounds, 1-（2-methyl-5-formyl-3- thienyl）-2-（2-methoxylphenyl）perfluorocyclopentene （1o） having an unsymmetrically substituted hexafluorocyclopentene unit, was synthesized and its structure was determined. The crystal belongs to the monoclinic system, space group P21/c with a = 15.4866（5）, b = 9.0744（9）, c = 12.6906（3）, β = 90.1480（10）°, Z = 4, V = 1783.4（3）3, Dc = 1.513 mg/m3, μ = 0.25, F（000） = 824, the final R = 0.0579 and wR = 0.1566 for 2584 observed reflections （I 2σ（I））. Interestingly, a colorless compound 1o undergoes photocyclization upon irradiation of UV light to give the blue isomer diarylethene. Upon irradiation with visible light with wavelength greater than 510 nm, the blue compound can return to its initial colorless state.

Simultaneous Enhancement of Electrical Conductivity and Seebeck Coefficient of Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate)Films Treated with Urea

The thermoelectric performance of free-standing poly(3,4-ethylenedioythiophene):poly(styrenesulfonate)(PEDOT:PSS)thin films deposited from aqueous dispersion treated by different concentrations of urea are investigated in detail.The electrical conductivity,Seebeck coefficient and power factor of PEDOT:PSS films versus temperature are determined,respectively.It is found that both the electrical conductivity and Seebeck coefficient of PEDOT:PSS films are enhanced after treatment with urea.Conductivity could be enhanced from 8.16 to 63.13S-cm^(-1),the Seebeck coefficient is increased from 14.47 to 20.7μV.K^(-1)and the power factor is rises to 2.7μW.m^(-1)K^(-2)at 300K.

ELECTROCHEMICAL COPOLYMERIZATION OF 3-(4-FLUOROPHENYL)THIOPHENE AND 3-METHYLTHIOPHENE IN BORON TRIFLUORIDE DIETHYL ETHERATE

The copolymer poly（3-（4-fluorophenyl）thiophene-co-3-methylthiophene） was successfully prepared from mixtures of 3-（4-fluorophenyl）thiophene （FPT） and 3-methylthiophene （MET） via electrochemical oxidation in boron trifluoride diethyl etherate （BFEE） and its mixed electrolytes with acetonitrile （ACN）. The influence of monomer concentration ratios on the copolymerization was investigated by using linear sweep voltammetry and cyclic voltammetry. The structure and morphology of these copolymer films were elucidated by UV-Vis, infrared spectroscopy, elemental analysis, thermal analysis and scanning electron microscopy （SEM）, respectively. The results showed that the molar ratio of FPT and MeT units, when copolymer was electrodeposited from feed ratio of FPT：MeT = 1：2, was about 1.08：1. In addition, the introduction of ACN into BFEE has little effect on the properties of as-formed copolymers.

Synthesis,Photochromism and Crystal Structure of 1-(2-Cyano-1,5-dimethyl-4-pyrryl)-2-[2-methyl-5-(3-pyridyl)-3-thienyl]perfluorocyclopentene

A new family of photochromic diarylethene compounds, 1-（2-cyano-l,5-dimethyl- 4-pyrryl）-2-[2-methyl-5-（3-pyridyl）-3-thienyl]perfluorocyclopentene （lo） having an unsymmetrical pyrryl and thienyl substituted hexafluorocyclopentene unit, was synthesized and its structure was determined by X-ray analysis. The crystal belongs to triclinic system, space group PI with a = 8.897（7）, b = 10.139（8）, c = 12.361（9） A, α = 85.222（7）, ρ = 75.439（7）, γ = 78.736（8）°, Z = 2, V= 1057.8（14） A3, D,.= 1.468 mg/m3, p = 0.220 mm-1, F（000） = 476, the final R = 0.0608 and wR = 0.1754 for 3199 observed reflections （1 〉20（/））. Interestingly, compound 1 exhibits good photochromic properties with alternate irradiation of UV light and visible light （〉 510 nm） to form two photoisomers in hexane solution and crystal phase.

Crystal Structure and Photochromic Properties of [1-(2-Methyl-5-(4-cyanophenyl)-3-thienyl)]-2-(2-methyl-5-phenyl-3-thienyl)perfluorocyclopentene

A new photochromic diarylethene, [1-（2-methyl-5-（4-cyanophenyl）-3-thienyl-2- （2-methyl-5-phenyl-3-thienyl）]perfluorocyclopentene （lo, C28H17F6NS2）, was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. Its crystal belongs to the monoclinic system, space group P21/c with a = 24.1381（5）, b = 9.3834（6）, c = 11.1073（8）, fl = 94.477（4）°, Z = 4, V= 2508.1（3） A3, Dc = 1.445 mg/m3, μ = 0.275, F（000） = 1112, the final R = 0.0482 and wR = 0.1429 for 5834 observed reflections （I 〉 2σ（I））. Further study demonstrated the diarylethene underwent reversible photochromism, changing between colorless and blue in hexane solution, crystalline phase and PMMA films, respectively.

Ionothermal Synthesis and Characterization of a Threedimensional Anionic Zinc-5-sulfoisophthalate Framework Charge-balanced with the 1-Ethyl-3-methylimidazolium

The ionothermal reaction of Zn（NO3）2·6H2O with 5-sulfoisophthalic acid monosodium salt（NaH2SIP） and 1,2,4-triazole in 1-ethyl-3-methylimidazolium tetrafluoroborate（EMIM-BF4） ionic liquid has afforded the compound {（EMIM）[Zn（SIP）]}n（1）.The Zn（Ⅱ） ions are linked by the carboxylate groups of SIP^3- ligands to give a two-dimensional layered structure featuring the centrosymmetric dinuclear Zn2（μ2-COO）2 units.The adjacent two-dimensional layers are further linked by the Zn-0 bonds between the Zn（Ⅱ） ions and the sulfonate O atoms to generate a three-dimensional anionic[Zn（SIP）]n^n- framework featuring one-dimensional open channels propagating along the a axis.The imidazolium cations[EMIM]^＋ derived from ionic liquid act as extraframework charge-balancing species for the anionic[Zn（SIP）]n^n- framework and occupy the void space of the one-dimensional open channels.The rich ionic environments of the ionic liquid may be particularly helpful in the formation of the ionic compound 1.The roles of the ionic liquid in ionothermal synthesis and crystallization of the compound are briefly discussed.Furthermore,compound 1 displays a photoluminescent emission at 490 nm upon excitation at 406 nm.

Crystal Structure and Photoreactive Properties of 1-(2,5-Dimethyl-3-thienyl)-2-[2-methyl-5-(N-(quinolin-8-yl)-2-carboxamide)-3-thienyl)]perfluorocyclopentene

The photochromic title compound,C_（26）H_（18）F_6N_2OS_2,contains a 2,5-dimethylthiophene ring and a N-formyl aminoquinolinyl thiophene ring on the C=C double bond of the cyclopentene ring.The dihedral angles between the cyclopentene and attached N-formyl aminoquinolinyl thiophene ring and 2,5-dimethylthiophene ring are 63.0° and 137.1°,respectively.The dihedral angle between the thiophene ring and the adjacent aminoquinoline ring is 5.7°.The molecule adopts an antiparallel conformation,with a distance between the two photoreactive C atoms of 3.763 ？.In addition,the absorption and fluorescence spectral changes were measured in acetonitile and solid at room temperature,and the result showed that the title compound could undergo photochromic reaction in both states.

Thermoelectric Performances of Free-Standing Polythiophene and Poly（3-Methylthiophene） Nanofilms

Thermoelectric performances of free-standing polythiophene （PT） and poly（3-methylthiophene） （PMeT） nanofilms with high tensile strength electrosynthesized from boron trifluoride diethyl etherate （BFEE） are systematically investigated. They display decent electric conductivity （47 and 73S.cm^-1）, high Seebeck coefficient （130 and 76μV.K^-1） and low thermal conductivity （0.17 and 0.15 W.m^-1.K^-1） at room temperature. Their figure of merit can reach 3.0 × 10^-2 at 250K, higher than that of many other conducting polymers. The decrease of charge carrier concentration resulting from volatile and water-sensitive dopants from BFEE leads to the decrease of electrical conductivity but a substantial increase of the Seebeck coet^cient, making their figure-of-merit values maintained at more than 10-2 even after prolonged storage （two months）. Moreover, free-standing PT and PMeT exhibit much better thermoelectric performances than those in pressed pellets due to the good arrangement of the polymer chains and preferably oriented structure in films. It therefore provides a way to improve the thermo- electric performances of conducting polymers by controlling regularity of the extended conjugated chain structure and/or the chain packing to achieve high charge mobility.

Crystal Structure and High Contrast Color-/fluorescent-switching Properties of 1-[2-Methyl-5-(4-chlorophenyl)-3-thienyl]-2-(2-methoxylphenyl)hexafluorocyclopentene

A new photochromic diarylethene, [1-（2-methyl-5-（4-chlorophenyl）-3-thienyl-2-（2- methoxylphenyl）]perfluorocyclopentene （1o, C23HIsC1F6OS） was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to the triclinic system, space group Pi with a = 9.421（1）, b = 10.4664（1）, c = 11.2988（2）, α= 88.014（1）, β= 76.976（1）,γ= 82.319（1）°, Z= 2, V= 1075.7（2） A3, Dc = 1.509 mg/m3, μ= 0.339 mm-1, F（000） = 496, the final R = 0.0353 and wR = 0.0922 for 3303 observed reflections （I 〉 2σ（I））. Further study demonstrated this compound underwent reversible photochromism with high contrast color-switching between colorless and blue in hexane. Upon UV/Vis irradiation, the fluorescence quenching efficiency can be attached to ca. 98% and recover to the initial state which exhibits high contrast fluorescentswitching between ＂on＂ and ＂off＂ states.

ELECTROCHEMICAL POLYMERIZATION OF 5-CYANOINDOLE IN MIXED ELECTROLYTES OF BORON TRIFLUORIDE DIETHYL ETHERATE AND DIETHYL ETHER

High quality poly（5-cyanoindole） （P5CI） films were electrosynthesized by direct anodic oxidation of 5-cyanoindole on stainless steel sheet in the mixed electrolytes of boron trifluoride diethyl etherate （BFEE） and diethyl ether （EE） （by volume 1：1） ＋ 0,05 mol L^-1 Bu4NBF4. The film formed can be peeled off the electrode into freestanding films, The addition of EE into BFEE can improve the solubility of monomer. P5CI films obtained from this medium showed excellent electrochemical behavior with conductivity of 10^-2 S cm^-1, Structural studies showed that the polymerization of 5-cyanoindole occurred at the 2,3 position. As-formed P5CI films were thoroughly soluble in strong polar organic solvent dimethyl sulfoxide （DMSO） while partly soluble in tetrahydrofuran （THF） or acetone. Fluorescence spectral studies indicated that P5CI was a good blue-ight emitter.

Crystal Structure and Crystalline State Multiphotochromism Properties of a Fused Diarylethene Dimer

The crystal structure of fused photochromic diarylethene dimer, 1,4-bis-[4-(4-{2-(5-phenyl)-2-methyl-thiophen-3-yl]-3,3,4,4,5,5-hexafluoro-cyclopent-1-enyl}-5-methyl-thiophen-2-yl) buta-1,3-diyne(1 oo, C46 H23 F12 S4) was determined by single-crystal X-ray diffraction analysis. This crystal belongs to the triclinic system, space group P1 with a = 7.546(3), b = 8.869(3), c = 16.196(5), α = 98.000(4)°, β = 100.803(4)°, γ = 98.449(4)°, Z = 2, V = 1037.6(6) ?~3, Dc = 1.496 mg/m^3, μ = 0.317, F(000) = 474, the final R = 0.0428 and wR = 0.1199 for 4115 observed reflections(I > 2σ(I)). Further study demonstrated this compound underwent reversible photochromism with color-switching between colorlessness and green in crystalline state. Upon 365 nm irradiation, the diarylethene shows one step photochromism to form isomer 1 oc. When irradiated with 312 nm, the stepwise photocyclization reactions occurred in diarylethene dimer through the line of 1 oo to 1 oc to 1 cc.

Syntheses, Crystal Structure and Magnetism of a Hexanuclear Copper(II) Cluster with the Unique Two-parallel Three-site Strings Configuration

Treatment of a heptadentate ligand 2,2＇-（（（pyridine-2,6-diyl-bis（methylene））- bis（（pyridin-2-ylmethyl）azanediyl））bis（methylene））diphenol （H2L） possessing pyridinyl- and phenolate groups, with three equivalents of Cu（C104）2·6H2O in methanol under base conditions, gave rise to a hexanuclear cluster complex [Cu6L2（OH）4]（C104）4·4MeCN·0.5MeOH （1）. Complex 1 crystallizes in triclinic, space group Pi with a = 12.068（12）, b = 12.567（12）, c = 16.279（16） A, α = 105.694（12）, β = 93.631（13）, γ = 112.017（11）°, V= 2166（4） A3, Z = 1,μ= 1.651 mm^-1, Dc = 1.599 Mg/m^3, T = 296（2） K, C74.5H795N14O24.5Cl4Cu6, Mr = 2086.12, F（000） = 1062.5, S = 1.061, R = 0.0521 and wR = 0.1270. In the cation of complex 1, the six copper cores are arranged into a two-parallel three-site strings configuration with each metal exhibits a slightly distorted square-pyramidal geometry, resulting from the connection of donor pyridinyi nitrogen and phenolate oxygen atoms in ligand H2L, and/or the oxygen donors in hydroxyl groups. In addition, magnetic susceptibility measurements revealed complex 1 displayed antiferromagnetic coupling.

Theoretical Studies on the Electronic Structures and Spectral Properties of 4,4′-(Ethane-1,2-diylbis-(oxy))dibenzaldehyde and Its Polymorph

The ground state geometries, frontier molecular orbital properties, and absorption properties of 4,4′-（ethane-1,2-diylbis（oxy））dibenzaldehyde （EDO-DBDHD） and its polymorph have been studied theoretically. The density functional theory （DFT） method was employed to optimize the ground state geometries, and theoretical data reveal that EDO-DBDHD features the planar molecular conformations, in contrast to V-shaped structures of its polymorph, which agrees with the experimental data. Additionally, the absorption spectra of both compounds were predicted using time-dependent density functional theory （TDDFT）. The calculated results show that the lowest lying absorption bands of these compounds have the transition configurations of HOMO → LUMO, resulting in the transition character of π→π＊/n→π＊. The transition of HOMO → LUMO＋3 mainly contributes to the highest lying absorption bands of two compounds at 225 nm with the character of π→π＊/n→π＊.

Removal of Microcystin-LR in lake water sample by hydrophilic mesoporous silica composites under high-throughput MALDI-TOF MS detection platform

Microcystins(MCs),a family of cyclic heptapeptide cyanotoxins,exists in aquatic environment where cyanobacterial bloom happens,which will accumulate in aquatic organisms and transfer through the food chain to higher trophic levels,posing a health risk to both animals and human bodies.Among various MCs,Microcystin-LR(MC-LR)is worthiest studied for its strong toxicity,ubiquity and widespread.Here in this work,iminodiacetic acid(IDA)decorated magnetic mesoporous silica(mSiO_(2))nanocomposites(Fe_(3)O_(4)@mSiO_(2)-IDA)were facilely synthesized which possessed the merits of large surface area(188.21 m^(2)/g),accessible porosity(2.66 nm),excellent hydrophilicity and rapid responsiveness to magnetic field.Then the composites were successfully employed to the removal process of Microcystin-LR in real water samples followed by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS)analysis,achieving the removal efficiency above 92.5%even after ten recycles of the composites.It provided a potential method for removing MC-LR in aqueous environment with high effectiveness,lower costs and less secondary contamination.

A Dinuclear Zinc(Ⅱ) Complex Derived from a ‘Click' Ligand Containing Phenol,Pyridine and Triazole Donors

A novel 1,2,3-triazolyl-containing ligand （H2L） with long donor arms extending from the central pyridyl linker was synthesized by click cycloaddition of 2,6-bis（azidomethyl）pyri- line and 2-（（prop-2-yn-1-yl（pyridin-2-ylmethyl）amino）methyl）phenol. Further treatment of the igand H2L with zinc（II） perchlorate in the presence of triethylaminc, followed by anion exchange vith Na[BPh4], provided a dinuclear zinc（II） complex [Zn2L][BPh4]E-2DMF （1）. Complex 1 crystallizes in monoclinic, space group P21 with a = 10.4873（4）, b = 14.9078（5）, c = 25.8620（9） A, = 94.566（2）°, V = 4030.5（2） A3, Z = 2,μ= 0.657 mm-1, Dc = 1.324 Mg/m3, T = 296（2） K, C93H91N13B2O4Zn2, Mr = 1607.19, F（000） = 1684, S = 0.958, R = 0.0271 and wR = 0.0607. In the tructurc of cation, the phenolate oxygen atoms of ligand act as the bridging nodes to form a hombic Zn2（OAr）2 core.

Remarkably Improved Gas Separation Performance of Polyimides by Forming“Bent and Battered”Main Chain Using Paracyclophane as Building Block

The design and development of highly permeable,selective and stable polymer membranes are great challenges in the gas separation industry.Herein,we constructed two intrinsic microporous polyimides(6FPCA and 6FMCA)derived from two isometric diamines(PCA and MCA),which were synthesized by palladium catalyzed C—N coupling reaction.The PCA and MCA diamines contain a hollow beaded structure of 2,2′-paracyclophane as a building block with a specified window size of 3.09Å.The chemical structures of monomers,polyimides were confirmed by NMR,FTIR,and elementary analysis.6FPCA and 6FMCA exhibit good solubility,excellent thermal stability,and mechanical properties.6FPCA exhibits much larger microporosity(434 versus 120 m2·g−1),FFV(0.22 versus 0.15),d-spacing(6.9 versus 5.9Å),and over 10 times higher permeability with a very little decrease in selectivity than the corresponding polyimide(6FpA)with a plane structure,which remarkably increased their separation performance from far below the 2008 Robeson Upper bounds to reach these limitations for O2/N2 and CO2/CH4.Additionally,the 6FPCA also demonstrates good plasticization resistance,moderate aging properties,and high CO2/CH4 mixed-gas separation performance.These results indicate that paracyclophane subunit can be successfully incorporated into polymers to enhance their ultra-microporosity and separation properties,which open a new avenue for developing high performance gas separation membranes with topological ultra-micropores.

Two new high-temperature molecular ferroelectrics[1,5-3.2.2-Hdabcn]X(X=ClO_(4)^(-),ReO_(4)^(-))

Molecular ferroelectrics have attracted much attention because of their excellent piezoelectricity,mechanical workability,and second harmonic effect.Here,we successfully prepared two molecular ferroelectrics[1,5-3.2.2-Hdabcn]X(X=ClO_(4)^(-),1;ReO_(4)^(-),2)by reactions of a quasi-spherical amine 1,5-diazabicycle[3.2.2]nonane(1.5-3.2.2-dabcn)with HX aqueous solution.Compounds 1 and 2 undergo hightemperature phase transitions at 381 K(1)and 396 K(2).Before and after the phase transition,they crystallize in the polar point group mm2,and the centrosymmetric point groups mmm and 4/mmm,respectively.According to Aizu rules,these two compounds experience mmm Fmm2 and 4/mmm Fmm2 type ferroelectric phase transitions,respectively.The ferroelectricity of both compounds is well expressed in their polycrystalline film at room temperature with low coercive voltages of 13 V for 1 and 25 V for 2.Using piezoelectric force microscopy(PFM),the 180°anti-parallel ferroelectric domains and the reversible polarization switching can be clearly observed in 1 and 2.This high-temperature molecular ferroelectric material has great application potential in flexible materials,biomechanics,intelligent wearables and other fields.