Structure Regulation of Electric Double Layer via Hydrogen Bonding Effect to Realize High-Stability Lithium-Metal Batteries

The interfacial chemistry of solid electrolyte interphases(SEI)on lithium(Li)electrode is directly determined by the structural chemistry of the electric double layer(EDL)at the interface.Herein,a strategy for regulating the structural chemistry of EDL via the introduction of intermolecular hydrogen bonds has been proposed(p-hydroxybenzoic acid(pHA)is selected as proof-of-concept).According to the molecular dynamics(MD)simulation and density functional theory(DFT)calculation results,the existence of hydrogen bonds realizes the anion structural rearrangement in the EDL,reduces the lowest unoccupied molecular orbital(LUMO)energy level of anions in the EDL,and the number of free solvent molecules,which promotes the formation of inorganic species-enriched SEI and eventually achieves the dendrite-free Li deposition.Based on this strategy,Li‖Cu cells can stably run over 185 cycles with an accumulated active Li loss of only 2.27 mAh cm^(-2),and the long-term cycle stability of Li‖Li cells is increased to 1200 h.In addition,the full cell pairing with the commercial LiFePO_(4)(LFP)cathodes exhibits stable cycling performance at 1C,with a capacity retention close to 90%after 200 cycles.

MOLECULAR DYNAMICS SIMULATION ON VIERATIONAL SPECTROSCOPIC FEATURES OF HYDROGEN BONDS IN CRYSTALLINE POLYMERS

Introduction The molecular dynamics simulation technique has recently proved to be a suitable alternative approachfor simulation of vibrational spectroscopy. In this study, molecular dynamics was utilized to understandlow frequency vibrations in highly ordered poly(ρ-phenylene terephthalmide) (PPTA). A key structuralfeature of this polymer is the presence of hydrogen bonds. There is little question that this strong localized

Theoretical Researches on the Recognizing Characteristics of Atrazine Imprinted Polymers with Different Functional Monomers

As a widely used herbicide, the threat of atrazine to both environment and health of people has become the focus. Therefore, the research and analysis of atrazine are getting more important. In this work, the MIT was used to detect atrazine theoretically. Atrazine was taken as a template molecule. MAA, MMA and TFMAA were taken as the functional monomers, respectively. The geometry optimization, the nature of hydrogen bonds, the NBO charge, and the binding energies of the imprinted molecule with the functional monomers were investigated at the B3LYP/6-31g（d,p） level. Results indicated that atrazine had the strongest interaction with TFMAA. When the ratio of atrazine and TFMAA was 1：6, the amount of H-bond formed from atrazine and TFMAA was the largest. Moreover, TFMAA owned the largest binding energy with atrazine while MMA owned the smallest. The study is helpful to interpret experiment phenomena of molecular imprinting and select better functional monomers.

Synthesis and Structural Characterization of a New Cadmium(II) Complex with a Double Betaine

A new flexible double betaine L （L = 1,4-bis（pyridinio-4-carboxylato-N-methyl）benzene, C20H16N2O4） and its cadmium（Ⅱ） complex [Cd（H2O）aL（NO3）]NO3.H2O 1 were synthesized. Complex 1 was obtained by self-assembly reaction of [Cd（NO3）2]-4H2O and L in hot water,and its crystal structure was determined by single-crystal X-ray diffraction analysis. Crystallographic data for complex 1： C20H24CdN4O14.H2O, Mr = 674.85, monoclinic, space group P21/c, a =13.7854（3）, b = 14.2820（3）, c = 14.9188（4） ,A°, β = 116.418（1）°, V = 2630.5（1）A°^3, Z = 4, Dc= 1.704g/cm^3,/J（MoKα） = 0.911 mm^-1, F（000） = 1368, the final R = 0.0315 and wR = 0.0768 for 3637 observed reflections with I 〉 2σ（I）. In complex 1, L acts as a monodentate ligand to link a Cd（Ⅱ） ion in a novel coordination mode of double betaines. The mononuclear [Cd（H2O）aL（NO3）] units are connected through intermolecular hydrogen bonds and π-π stacking reactions to generate a 3D network.

Synthesis and Crystal Structure of a 1D Chained Coordination Polymer Containing One-dimensional Egg-like Channels:{[Cu_2(C_2O_4)_2(inta)_4](inta)}_n (inta=Isonicotinamide)

A new one-dimensional copper coordination polymer chain has been prepared and fully characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The compound { [Cu2（C2O4）2（inta）4]（inta）}n 1 crystallizes in the triclinic system, space group P1, with a = 8.4722（5）, b = 10.9825（6）, c = 11.6128（6）A, α= 104.8050（10）,β = 102.5740（10）, γ= 109.6890（10）°, V= 927.18（9） A3, Mr = 929.79, Z = 1, Dc = 1.665 g/cm^3, F（000） = 475, μ = 1.231 mm^-1, R = 0.0453 and wR = 0.1185 for 3290 observed reflections （Ⅰ 〉 2σ（Ⅰ））. Of the compound, the Cu center is octahedrally coordinated with oxalate acting as a tetra-dentate ligand coordinated to the copper atom and each inta serving as a terminal ligand by employing only one N-donor to coordinate with the Cu center. An infinite {Cu2（C2O4）2}∞ chain is formed along the c axis. Furthermore, the 1D chains are held together via extensive hydrogen-bonding interactions to generate a three-dimensional network with 1D channels （ca. 5.491A×11.507A） where inta molecules are filled.

Hydrothermal Synthesis and Crystal Structure of a Zinc(Ⅱ)Coordination Polymer Assembled by Dpphen and H_2btec/btec

A new metal-organic coordination polymer [Zn2（dpphen）2（H2btec）（btec）0.5]n （dpphen = 4,7-diphenyl- 1,10-phenanthroline, H4btec = 1,2,4, xylic acid） 1 was obtained via hydrotherrnal synthesis and characterized by elemental analysis, TG; IR spectrum and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group P2 1/n with a = 16.2996（14）, b = 14.3332（12）, c = 25.247（2） A, β = 103.4050（10）°, V= 5737.7（9） A）, C63H37N4O12Zn2, Mr = 1172.71, Dc = 1.358 g/cm3,μ（MoKα） = 0.902 mm^-1, F（000） = 2396, Z = 4, the final R = 0.0684 and wR = 0.1281 for 3728 observed reflections （1 〉 2σ（I））. It exhibits a two-dimensional network structure constructed by mixed ligands of dpphen and H2btec/btec.

Syntheses and Crystal Structures of Two 3D Zinc(II) Compounds Involving Coordination and Hydrogen Bonds

Two zinc（Ⅱ） compounds, [Zn（L）（H2O）2]n 1 and [Zn（4,4＇-bpy）（H2O）4]（L） 2 （H2L = trans,trans-1,3 butadiene 1,4-dicarboxylic acid）, were synthesized by hydrothermal methods and characterized by single-crystal X-ray diffraction analyses. Compound 1 crystallizes in monoclinic, space group C2/c with a=15.4970（16）, b = 5.4976（6）, c = 10.7113（12） A, β=96.298（6）°, C6H8O6Zn, Mr = 241.50, V = 907.06（17） A^3, Z = 4, D, = 1.768 g/cm^3, F（000） = 488,μ = 2.703 mm^-1, S = 1.060, the final R = 0.0256 and wR = 0.0660 for 968 observed reflections with Ⅰ 〉 2σ（Ⅰ）. Compound 2 crystallizes in triclinic, space group P1^- with a = 6.915（2）, b = 7.166（2）, c = 10.363（3） A, α = 73.250（4）, β = 84.429（4）, γ = 61.605（3）°, C16H2ON2O8Zn, Mr = 433.70, V = 432.1 （2） A^3, Z = 1, D, = 1.667 g/cm^3, F（000） = 224 and μ= 1.471 mm^-1, S = 1.118, the final R = 0.0486 and wR = 0.1077 for 1352 observed reflections with Ⅰ〉 2σ（Ⅰ）. Upon using the assembly strategy of combination of coordination polymer chains with intermolecular hydrogen bonds, three-dimensional frameworks of complexes 1 and 2 were formed.

Transition metal coordination polymers with flexible dicarboxylate ligand:Synthesis,characterization,and photoluminescence property

Under solvothermal conditions,six new coordination polymers(CPs)[Mn(L)(phen)(H_(2)O)]_(n)(1),[Co(L)(phen)(H_(2)O)]_(n)(2),[Cu(L)(phen)(H_(2)O)]_(n)(3),[Zn_(2)(L)_(2)(phen)2(H_(2)O)]_(n)(4),[Zn(L)(phen)]_(n)(5),and[Cd(L)(phen)2]_(n)(6)were synthesized by reactions of dicarboxylate ligand 2,2'-(1,2-phenylenebis(methylene))bis(sulfanediyl)dinobutyric acid(H_(2)L)and 1,10-phenanthroline(phen)with the corresponding metal salts.Complexes 1-6 have been structurally characterized by single-crystal X-ray diffraction analyses,elemental analysis,IR,thermogravimetric analysis,and powder X-ray diffraction.The structures of 1-6 are 1D chains,which are further connected by hydrogen bonding interac-tions to form 3D supramolecular structures.Among them,1 and 2 are isomorphic with L2-of syn-conformation,while L2-shows anti-conformation in 3-6.In addition,the solid-state photoluminescence property of 4-6 was investigated.

Synthesis, Crystal Structure and Property of a Series of Supramolecular Polymers Based on Novel 3,5-Dimethyl- 2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl)pyridine Ligand

Solvothermal reactions of 3,5-dimethyl-2,6-bis（3-（pyrid-2-yl）-1,2,4-triazolyl） pyridine （L）, 1,4-benzendicarboxylic acid （H2bdc）, and transitional metal cations of M11 （M = Mn, Co, Cd） in the presence of oxalic acid （H2ox） afford three novel supramolecular polymers （CPs）, namely, {[M2（ox）（L）2][bdc][M2（Hox）2（OH）（H2O）4]·3H2O}n （M = Mn for 1, Co for 2, Cd for 3）. Single-crystal X-ray diffraction analysis reveals that complexes 1-3 are isostructural and the 3D supramolecular structure was connected through non-covalent interactions. With the help of H2ox, the L ligands cheated with center atoms forming a butterfly [M2（ox）（L）2]2＋ building block. The bdc2- ligand linked with the unprecedented [M2（Hox）2（OH）2（H2O）4] units through strong O-H...O hydrogen bonds forming a zigzag chain, which are further connected through π-π interactions between L and bdc2- ligands to form a 3D supramolecular structure. Moreover, elemental analyses, IR, thermogravimetric, PXRD and luminescence have been investigated.

In Situ High-performance Gel Polymer Electrolyte with Dual-reactive Cross-linking for Lithium Metal Batteries

Lithium metal batteries have been considered as one of the most promising next-generation power-support devices due to their high specific energy and output voltage.However,the uncontrollable side-reaction and lithium dendrite growth lead to the limited serving life and hinder the practical application of lithium metal batteries.Here,a tri-monomer copolymerized gel polymer electrolyte(TGPE)with a cross-linked reticulation structure was prepared by introducing a cross-linker(polyurethane group)into the acrylate-based in situ polymerization system.The soft segment of polyurethane in TGPE enables the far migration of lithium ions,and the-NH forms hydrogen bonds in the hard segment to build a stable cross-linked framework.This system hinders anion migration and leads to a high Li^(+)migration number(t_(Li^(+))=0.65),which achieves uniform lithium deposition and effectively inhibits lithium dendrite growth.As a result,the assembled symmetric cell shows robust reversibility over 5500 h at a current density of 1 mA cm^(-2).The LFP∷TGPE∷Li cell has a capacity retention of 89.8%after cycling 800 times at a rate of 1C.In summary,in situ polymerization of TGPE electrolytes is expected to be a candidate material for high-energy-density lithium metal batteries.

Hydrothermal synthesis and structural studies of a new coordination polymer of lanthanum(Ⅲ) with benzene-1,2,4,5-tetracarboxylic acid and 4,4′-bipyridine

A new lanthanum complex formulated as {（bpyH2）[La（btc）（H2O）4（NO3）]·2H2O}n （1） （btcH4=benzene-1,2,4,5-tetracarboxylic acid; bpy=4,4＇-bipyridine） was hydrothermally synthesized. The complex was characterized by FT-IR spectroscopy, elemental analysis and X-ray diffraction. X-ray crystal structural analysis revealed that the compound belonged to the monoclinic space group C2/c with cell parameters a= 1.42806（7） nm, b=1.10258（5） nm, c=1.60333（8） nm and β=101.9400（10）°. The complex was polymeric with La^III atoms linked by four O atoms from two carboxylate groups of one benzene-1,2,4,5-tetracarboxylate. The LaIn atom was ten coordinated in a distorted tetracapped trigonal prism. In the crystal structure, a wide range of noncovalent interactions consisting of hydrogen bonding （of the types of O-H…O, N-H…O and C-H…O） and ion pairing interactions connected the various components into a supramolecular structure.

SYNTHESIS AND CHARACTERIZATION OF WELL-DEFINED BLOCK COPOLYMERS CONTAINING PENDANT,SELF-COMPLEMENTARY QUADRUPLE HYDROGEN BONDING SITES

The title block copolymer (defined as PSUEA) containing pendant,self-complementary quadruple hydrogen bonding sites has been prepared successfully by three steps.First,poly(styrene-b-2-hydroxyethyl acrylate) (defined as PSHEA) was prepared by living radical polymerizing 2-hydroxyethyl acrylate (HEA) initiated by polystyrene (PSt) macro- initiator,which was prepared via nitroxide-mediated polymerization (NMP) technique.After treated by excessive 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI),...

Syntheses and Structures of Three Novel 1-D Lanthanide-isonicotinate Coordination Polymers

Three novel lanthanide-IN coordination polymers [Ln（IN）3（H2O）2], （Ln = Sm 1, Dy 2, Eu 3; IN = isonicotinate） have been hydrothermally synthesized and characterized by FT-IR spectra, elemental analysis and TG analysis. Single-crystal X-ray diffraction shows that 1, 2 and 3 are isostructural. Crystal data for 1： monoclinic, space group C 2/c, a = 15.8384（14）, b = 14.2662 （12）, c = 9.5073（7） A, β = 97.705（4）°, V = 2128.8（3） A^3, Z = 4, Dc = 1.724 g/cm^3, F（000） = 1084 , μ = 2.806 mm^-1 and R = 0.0226; Crystal data for 2： monoclinic, space group C 2/c, a = 15.7890（3）, b = 14.1356（6）, c = 9.5152（3） A, β= 97.899（2）°, V = 2103.52（12） A^3, Z = 4, Dc = 1.784 g/cm^3, F（000） = 1100, μ = 3.601 mm^-1 and R = 0.0406; Crystal data for 3： monoclinic, space group C 2/c, a = 15.802（5）, b = 14.242（4）, c = 9.513（3） A, β = 97.695（5）°, V = 2121.8（10） A^3, Z = 4, Dc = 1.735 g/cm^3, F（000） = 1088 ,μ = 3.004 mm^-1 and R = 0.0273. In the three compounds, the Ln（Ⅲ） centers are eight-coordinated with antiprismatic geometry. The Ln（IN）3（H2O）2 unit connects mutually to form a one-dimensional double zigzag chain via isonicotinate oxygen bridging. The infinite chains are further linked by inter-chain hydrogen-bonding to form a three-dimensional supramolecular network.

Synthesis of comb bipolymers and their pour point depressing properties

A bipolymer maleic anhydride-methyl acrylate （MAMA） was synthesized from maleic anhydride and methyl acrylate based on molecular design.MAMA further reacted with oleylamine or octadecyl alcohol to generate two comb polymers called Oleamide-MAMA （NMAMA） and OctadecanolMAMA （OMAMA）,respectively.The structure of both the polymers was confirmed by their infrared spectral analysis （IR）,gel permeation chromatography analysis （GPC） and differential scanning calorimeter （DSC）.Moreover,the pour point depressing （PPD） properties of these comb polymers were examined experimentally.Experimental results showed that besides the molecular weight and concentration of the polymers,the length of side chains and the number of functional groups also had great influence on the pour point depressing performance.The π bonds and hydrogen bonds between depressants were the key factors for improving the pour point depressing properties.These results suggest that both OMAMA and NMAMA are potential pour point depressants for industry.

Syntheses and Structures of Two New Coordination Polymers:[Cu(C_(14)H_9O_4)(C_(14)H_(10)O_4)(C_(12)H_(12)N_2)_2] and [Ag(C_(14)H_9O_4)(C_(13)H_(14)N_2)]·0.5H_2O

Under hydrothermal conditions, two new ribbon-like structures, [Cu(C14H9O4)- (C14H10O4)(C12H12N2)2] 1 and [Ag(C14H9O4)(C13H14N2)]0.5H2O 2, were obtained. X-ray crystal analysis revealed that these structures were constructed by mixed ligands. The coordination polymer forms the basic architecture while the weak interactions extend the framework into a secondary structure. The whole structures of them are governed by collaboration of the strong and weak interactions. Compound 1 crystallizes in monoclinic, space group C2/c with a = 17.0485(3), b = 11.0558(3), c = 22.7623(4) ? ?= 102.465(1), V = 4189.2(2) 3, Z = 4, Mr = 915.44, Dc = 1.451 g/mL, F(000) = 1904 and m(MoKa) = 0.587 cm-1. The final R and wR are 0.0430 and 0.1022, respectively for 3037 observed reflections with I > 2s(I). Compound 2 crystallizes in monoclinic, space group P21/c with a = 11.5963(4), b = 11.7004(5), c = 17.1254(5) ? ?= 95.620(1), V = 2312.4(1) 3, Z = 4, Mr = 556.35, Dc = 1.598 g/mL, F(000) = 1132 and m(MoKa) = 0.912 cm-1. The final R and wR are 0.0431 and 0.1050, respectively for 2629 observed reflections with I > 2σ(I).

Hydrothermal Syntheses, Crystal Structures and Fluorescence of a Copper(I) Polymer and a Salt with H_2SO_4 Based on a Pyrimidine Building Block

Based on the building block of 2-phenyl-4,6-di（pyridin-2-yl）pyrimidine （L = C20H14N4）, a Cu（I） polymer [（CuC20H14N4）（CuCl2）]∞ and a salt with H2SO4 [（C20H16N4）（HSO4）2] have been synthesized by hydrothermal method and characterized by X-ray single-crystal diffraction. In the Cu（Ⅰ） polymer, although the central metal ions of Cu（Ⅰ） directly coordinate with the building block L, they still do not assembly expected grid-type complexes and there exists a one-dimensional chain constructed through coordinate bonds. In the salt, hydrogen bonds along with two kinds of π…π supramoleuclar interactions fabricate two-dimensional （2D） networks which further generate a 3D supramolecular architecture via interlayer π…π interactions. Fluorescent spectra show that the L emits blue fluorescence and its Cu（Ⅰ） polymer and salt decrease the fluorescent intensity.

Crystal Structure of the Coordination Polymer of Sodium with Hydrazone Derivant of Acetoacetanilide

One new polymer, [Na（NPHSNPAB）（CH3OH）]n, where NPHSNPAB stands for Nphenyl-2-[2-hydroxy-3-sulfo-5-nitrophenylhydrazone]butadione-1,3, has been synthesized and characterized by ^1H NMR and FTIR spectroscopy and single-crystal X-ray diffraction. For this complex： C（17）H（17）N4NaO9S, Mr = 476.39, triclinic system, space group P1, a = 8.8741（18）, b = 10.942（2）, c = 12.039（2） A, α = 65.74（3）, β = 77.49（3）, γ = 84.30（3）o, V = 1040.3（4） A3, Z = 2, Dc = 1.521 g/cm^3, λ = 0.71073 A, F（000） = 492, S = 1.106, R = 0.0614 and w R = 0.1423 for 2945 observed reflections with I 〉 2（I）. X-ray structural analysis revealed that the structure of NPHSNPAB framework was almost planar by C–H···O, N–H···O, O–H···O, and O–H···S hydrogen bonds. Moreover, sodium（I） center was bound by six O and one N atoms, forming the coordination polymer. The molecular packing diagram showed complicated hydrogen bonds and π···π stacking interaction in the polymer. The average bond distance of the two dicyclic units（3.768 A） indicated strong π···π stacking interaction. The complex displays greenyellow emission at room temperature.

Syntheses and Crystal Structures of Two New One-dimensional Double Hydrogen-bonding-chain Complexes [Ni(bipy)_2Cl]·ClO_4 and [Zn(bipy)_2Cl]·BF_4

Two new transition metal complexes, [Ni（bipy）2Cl]·ClO4 （bipy = 2,2＇-bipyridine） 1 and [Zn（bipy）2Cl]·BF4 2, have been synthesized and characterized by single-crystal X-ray diffraction analysis. Both 1 and 2 crystallize in monoclinic space group P21/n with Z = 4. For 1, a = 10.776（1）, b = 12.067（1）, c = 16.146（2）A, β = 93.021（2）o, V = 2031.9（4） A^3, Mr = 505.98, Dc = 1.654 g/cm^3, μ = 1.255 mm^–1, F（000） = 1032, the final R = 0.0406 and wR = 0.1002 for 3983 observed reflections with Ⅰ 〉 2σ（Ⅰ）. For 2, a = 10.758（4）, b = 12.058（4）, c = 16.135（5） A, β = 104.57（1）o, V = 2025.7（12） A^3, Mr = 500.00, Dc = 1.639 g/cm^3, μ = 1.396 mm^–1, F（000） = 1008, the final R = 0.0470 and wR = 0.1237 for 3759 observed reflections with Ⅰ 〉 2σ（Ⅰ）. The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. A one-dimen-sional zigzag double hydrogen-bonding-chain is generated by the intermolecular M-bipy ···anion···bipy- M hydrogen bonding interactions between the chelating ligands of bipy and anion.

Polymer Coatings for Protection of Wood and Wood-Based Materials

Three major types of protective coating of wood and wood-based materials have been considered. These three types include the coatings based on carboxyl-containing water-soluble polymers which are easily cross-linked by inorganic salts or OH-containing compounds, pH-sensitive coatings and polymer multi-layer structures. First of three mentioned approaches allows affecting permeability and enhancing the prevention the loss of water from the surface of wood to its surrounding. The advantage of the second approach is its ability to vary and purposely adjust the polymer composition and the number and distribution of -COOH groups in the chain which make the originally water-soluble polymers completely insoluble. The strong feature of the third approach which includes broad use of hydrogen-bonded films produced by layer-by-layer self-assembly is the possibility of manipulation of coatings stability after construction.

A New Co(Ⅱ) Coordination Polymer Based on a Flexible 1,4-Cyclohexanedicarboxylic Acid: Synthesis, Structure and Thermal Behavior

A new Co（Ⅱ） coordination polymer, [Co（1,4-chdc）（L）（H2O）]n（1）, was synthesized under hydrothermal condition（1,4-H2chdc = 1,4-cyclohexanedicarboxylic acid, L = 2-（4-fluoro-phenyl）-1 H-imidazo[4,5-f][1,10]phenanthroline）. Its crystal structure was determined by single-crystal X-ray diffraction. 1 crystallizes in triclinic, space group P1 with a = 8.790（5）, b = 10.486（5）, c = 13.305（5） ?, α = 87.391（5）, β = 82.925（5）, γ = 81.841（5）o, V = 1204.2（10） ?3, Z = 2, C27H23FN4O5Co, Mr = 561.42, Dc = 1.548 g/cm3, F（000） = 578, μ（Mo Ka） = 0.769 mm-1, R = 0.0415 and wR = 0.1043. In 1, each 1,4-chdc anion bridges two neighboring Co（Ⅱ） atoms to give a chain structure. The L ligands are attached on one side of the chain through chelating the Co（Ⅱ） atoms, and are stacked with those of an adjacent chain through π-π interactions, yielding a double-chain structure. The double-chain structures are linked into a supramolecular layer structure through N–H···O hydrogen-bonding interactions between the adjacent double-chain structures. Moreover, the thermal behavior of 1 was also studied.