The etching strategy of zinc anode to enable high performance zinc-ion batteries

Zinc-ion batteries(ZIBs)are considered to be one of the most promising candidates to replace lithium-ion batteries(LIBs)due to the high theoretical capacity,low cost and intrinsic safety.However,zinc dendrites,hydrogen evolution reaction,surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode,which will seriously affect the cycle stability of the battery and hinder its practical application.The etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects,and the etched Zn anode can effectively improve its electrochemical performance.However,there is no comprehensive review of the etching strategy of Zn anode.This review first summarizes the challenges faced by Zn anode,then puts forward the etching mechanisms and properties of acid,salt and other etchants.Finally,based on the above discussion,the challenges and opportunities of Zn anode etching strategy are proposed.

Unveiling and Alleviating Chemical“Crosstalk”of Succinonitrile Molecules in Hierarchical Electrolyte for High-Voltage Solid-State Lithium Metal Batteries

Succinonitrile-based plastic crystal electrolytes have emerged for high-energy-density Li metal batteries in terms of their superior ambient ionic conductivity,low flammability,and benign compatibility with high voltage cathode,but are hampered by inherent instabilities toward Li anodes.Constructing hierarchical solid electrolytes structure is a fundamental approach to protect Li anode from succinonitrile attacks,with succinonitrile-based oxidation-resistance layer facing high voltage cathode and reduction-tolerant layer contacting Li anode.However,free succinonitrile molecules in succinonitrile-based electrolyte layer can diffuse across the electrolyte/electrolyte interface and further reach Li anode surface during the battery cycle.This chemical“crosstalk”cause reduction-tolerant electrolyte layer to fail to protect the Li anode from the attacks of free succinonitrile molecules.Nano Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)is introduced creatively into succinonitrile-based electrolyte layer.By taking advantage of the complexation between La atoms in Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)and N atoms in succinonitrile,the free succinonitrile molecules are successfully immobilized in succinonitrile-based electrolyte layer.The resulting low resistance and highly durable solid electrolyte interphase and cathode electrolyte interphase endow NCM622||Li batteries with remarkable cycle stability.Our research provides a new idea for the real application of plastic crystal electrolytes in high voltage solid-state lithium metal batteries.

Enhancing long-term stability of bio-photoelectrochemical cell by defect engineering of a WO_(3-x) photoanode

Bio-photoelectrochemical cells(BPECs)can further expand the use of conventional biofuel cells for renewable energy,but the poor stability of the photoelectrode still hinders their practical application.Herein,a BPEC capable of long-term operating in a fuel-free model is fabricated by WO3-xphotoanode with oxygen vacancy(Ov)and bilirubin oxidase catalyzed biocathode.The construction of Ov on the WO3surface significantly suppresses the dissolution of W species into the electrolyte,and improves the charge separation efficiency and the reaction kinetics during the photoelectrochemical oxygen evolution process,thus enhancing the stability and power output performance of the BPEC.As a result,the assembled BPEC can output an open circuit voltage of 0.81 V and deliver a maximum output power of up to 283μW cm^(-2).Impressively,the BPECs maintain 97%of their original power after 36000 s of consecutive discharge under an enclosed environment.This fuel-free BPEC based on a robust WO3-xphotoanode shows excellent promise for accurate application.

Syntheses and Characterizations of Two New Organic-inorganic Hybrids Based on Heteropolymolybdates and Piperidine Molecules

Two new organic-inorganic compounds [（CH2）5NH2]3[PMo12O40]·3[（CH2）NH] 1 and [（CH2）5NH2]6[P2Mo18O62]·5H2O 2 have been synthesized using conventional and hydrothermal methods, respectively, and characterized by elemental analyses, IR, TG and single-crystal X-ray diffraction. X-ray analyses show that in these compounds heteropolymolybdates [PMo12O40]^3- and [P2Mo18O62]^6- are reserved their Keggin or Dawson structures and linked to piperidine through electrostatic and hydrogen-bonding interactions.

Synthesis and Structure of 1.5Zn(phen)_3·L·3NO_3 Supramolecule(phen=o-Phenanthroline,L=4-Aminoacetophenone Thiosemicarbazone)

A supramolecular framework, 1.5Zn（phen）3·L·3NO3 （C63H48Zn1.5N16O9S）, has been synthesized. The ligand L was synthesized by the condensation of p-aminoacetophenone with thiosemicarbazide. The crystal belongs to the monoclinic system, space group C2/c, with a = 31.005（2）, b = 15.114（2）, c = 24.887（3） A, β = 94.260（2）° Z = 8, V = 11630（2）A^3 Dc = 1.489 g/cm^3, Mr = 1303.29,λ（MoKa） = 0.71069 A,μ= 0.735 mm^-1, F（000） = 5368, Rint = 0.0699, R= 0.0505 and wR= 0.0707. Two independent Zn atoms are both coordinated by six N atoms from three phen ligands. π-π and C-H…π interactions among the L ligands and Zn（phen）3 cations, π-π and C-H...π interactions among the Zn（phen）3 cations and N-H...O hydrogen bonds among the L ligands and nitrate anions connect the whole structure into a 3-D supramolecular framework.

Electro-oxidation of Ascorbic Acid on PVP-stabilized Graphene Electrode

Polyvinylpyrrolidone-stabilized graphene（PVP-graphene） was synthesized and investigated as a modifier for the determination of ascorbic acid（AA）. With PVP acting as stabilizer and dispersant, the resulting PVP-graphene material could disperse well into water. And the PVP-graphene modified glassy carbon electrode（PVP-graphene-GCE） showed an obvious electrocatalytical activity toward the oxidation of AA in a phosphate buffer solution（PBS, pH=7.0） with an oxidation potential of AA at 0.052 V vs. AglAgCl（sat. KCl）. The calibration curve for APt was linear in a concentration range from 1.0×10^-5 to 5.0×10^-4 mol/L with a correlation coefficient of 0.9998. And the detection limit was found to be 1 μtmol/L. During the oxidation of AA, the π-π interaction of graphene plane with conjugated hexenoic aeid-lactone in AA molecules might play a key role. As a result, an obvious decrease of overpotential was achieved at such a PVP-graphene electrode through a possible adsorption/enrichment process, which will probably trigger potential applications for the electroanalysis of some aromatic and heterocyclic compounds.

A new chain-like heteropolytungstate formed by Keggin cluster units:Synthesis and structure of[H2bpy]3[SiMnW(11)O(39)].1.25H2O

A new heteropolytungstate, [H2bpy]3[SiMnW11O39]· 1.25H2O （1）, has been prepared under mild hydrothermal conditions and structurally characterized by single crystal X-ray diffraction. It is the first characterized compound containing ID zigzag chain of transition metal substituted Keggin heteropolytungstate, which is connected through a common oxygen atom. The elemental analysis and IR of it are also described.

Controllable Synthesis of CaCO_3 Micro/Nanocrystals with Different Morphologies in Microemulsion

Lens-like vaterite CaCO3 microrings composed of CaCO3 nanoparticles were synthesized via a microemulsion-mediated route at room temperature with ethanol and n-hexanol as co-surfactant. This process did not demand any additional energy such as heating or continuous agitation. It was the first time to use ethanol as co-surfactant in the synthesis of micro or nanomaterials. And the ethanol was believed to play an important role in the aggregation fashion of CaCO3 nanoparticles. Moreover, shuttle-shaped nanorods, hexagonal nanoplates, and rice-like nanoparticles were also fabricated by modulating the growth parameters. Additionally, the introduce of ethanol into microemulsions as co-surfactant may be generalized as a novel green route to control the structure of other functional materials.

A Novel Dimer──Heteropolytungstate with a Vanadium Atom as the Centre ──Synthesis and Structural Characterization of (H_3O)_4[VW_(12)O_(40)Na(H_2O)_4]_2

A novel dimer tungstovanadate, (H 3O) 4[VW 12 O 40 Na(H 2O) 4] 2, was hydrothermally synthesized and structurally characterized by single crystal X ray diffraction, IR spectra, TGA DSC thermal analysis and polarograpy. The yellowish crystal crystallized in the triclinic system, space group P1, a =1 464 5(3) nm, b =1 468 6(3) nm, c =1 411 1(3) nm, α=111 82(2)°, β=93 17(3)°, γ=117 47(3)°, V =2 210 6(8) nm 3, Z=1, D c=4 552 g·cm -3 , λ (Mo Kα )=0 071 073 nm, μ =31 402 mm -1 , F(000)=2 648, R =0 078 0. The title compound consists of two Keggin structure units linked together with two hydrated sodium cations to form a dimer with a porous structure with the pore dimension of 0 766 nm×0 778 5 nm. [WT5FZ]

Crystal Structure and Electronic Structure of a Luminescent Compound 2-(2-Pyridyl) Benzimidazole

The crystal structure of 2-(2-pyridyl) benzimidazole was determined by single- crystal X-ray diffraction at 193(2) K. It crystallizes in orthorhombic system, space group Pbca with unit cell constants a = 10.6204(7), b = 10.1407(4), c = 18.6327(8) , Z = 8, V = 2006.7(2) 3, Dc = 1.292 g/cm3, F(000) = 816 and m(MoK) = 0.081 mm-1. The structure was refined to R = 0.0317 and wR = 0.0454 for 795 observed reflections with I > 2s(I). In the solid state, it has an emission maximum at 369 nm, while in solution (DMSO), the maximum excitation is at 372 nm. Quantum chemistry calculation was performed by the method of density functional theory. Theoretical results show that atom N is the reactive site when coordinating with a metal, and the electronic structure of the title compound presents excellent carrier transport properties.

Synthesis of α-Oxoketene CyclicO,S and S,S Acetals

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Portable and automated analyzer for rapid and high precision in vitro dissolution of drugs

We developed a novel portable and automated dissolution test analyzer for rapid and high precision in vitro dissolution testing of drugs.The analyzer consists of a flow-through-cell drug dissolution system,an automated sequential sampling system,a high-speed capillary electrophoresis(HSCE)system,and a data acquisition system.Combining the high-temporal resolution flow-gating sampling approach with HSCE,which has outstanding advantages of efficient separation and resolution,the analyzer can achieve rapid analysis and exhibits the ability in miniaturization for on-site assessment of different active pharmaceutical ingredients.To integrate the flow-through-cell dissolution system with HSCE,a specially designed flow-gating-injection(FGI)interface was employed.The performance of the analyzer was investigated by analyzing the dissolution of immediate-release drugs including single dose(amoxicillin dispersible tablets)and fixed dose combination(amoxicillin and clavulanate potassium)drug tablets with the high-temporal resolutions of 12 s and 20 s,respectively.The dissolution profiles of different active pharmaceutical ingredients could be simultaneously and automatically monitored with high repeatability and accuracy.The analyzer was successfully utilized for the pharmaceutical quality control and bio-relevant dissolution testing,as well as in vivo-in vitro correlation analysis.Our portable analyzer is miniaturized,convenient and of low-cost,and will provide a valuable tool for dissolution testing in pharmaceutical research and development.

Facile and Convenient One-pot Synthesis of 1,1-Disubstituted Cyclopropanes in Water

A facile and convenient one-pot synthesis method of substituted cyclopropanes in water has been developed. A series of 1,1-disubstituted cyclopropanes 3 were synthesized from the reaction of β-dicarbonyl compounds 1 with 1,2-dibromoethane 2, in very high yields catalyzed by tetrabutylammonium bromide（TBAB） at 50 ℃ in the presence of K2CO3 in water. The catalyst TBAB in the aqueous phase can be reused after the separation of organic products.

Hydrothermal Synthesis and Structure of [CH3NH3]2[(VⅣO)2(VⅤO4)2]:A New Layered Mixed-valence Vanadium Oxide Incorporated with Organic Cations

A new layered mixed valence vanadium oxide, [CH 3NH 3] 2[(V ⅣO) 2(V ⅤO 4) 2], which contains interlamellar organic cations was prepared under hydrothermal conditions and its single crystal structure was determined. It crystallizes in a triclinic system with space group P 1, a =0 625 59(8) nm, b =0 639 84(9) nm, c =0 747 19(10) nm, α =78 718(2)°, β =80 099(2)°, γ =77 100(2). The compound contains mixed valence V 4+ /V 5+ vanadium oxide layers constructed from VO 4 tetrahedra, pairs of edge sharing VO 5 square pyramid and methylamine with protonated organic amines occupying the interlayer space.

Mechanisms of Cytochrome C Extraction by Reverse Micelles

The extraction of cytochrome C was carried out by means of phase transfer technique with three different reverse micellar systems, i.e. , a CTAB micellar solution in n butyl alcohol chloroform(volume ratio 4∶1), an AOT micellar solution in isooctane and a SDSS D 2EHPA micellar solution in isooctane. The extraction mechanisms were studied. The results show that the extraction mechanisms for the same proteins with different types of reverse micellar systems can be distinct. The extraction of cytochrome C with CTAB and SDSS D 2EHPA reverse micellar systems are carried out according to the mechanism of electrostatic interaction. However, in the extraction of cytochrome C with the AOT reverse micellar system, the electrostatic interaction between the protein and the surfactant is not important.

Synthesis, Structure Characterization and Biological Activity of Layered Vanadium Oxides [NH_3(CH_2)_2NH(CH_2)_2NH_3][V_6O_(14)]

A new layered vanadium oxide [ NH3 （ CH2 ）2NH（ CH2 ）2NH3 ] [ V6O14 ] （ compound 1 ） was synthesized and characterized by elemental analysis, IR spectrometry and single crystal X ray diffraction. The compound crystallizes ina monoclinic space group P2（1）/n with a = 1.0254（2） nm, b =0.6739（2） nm, c = 1.2400（2） nm, ,8 = 93.88 （ 3 ） °, V = 0. 8549 （ 3 ）nm^3, Z = 2, R1 = 0. 0366, wR2 = 0. 1038. Compound 1 consists of two-dimensional mixed-valence vanadium oxide layers parallelling to the bc plane. The anti-tumor activity of the compound was estimated in three human tumor cell lines in vitro.

Synthesis and Characteristics of Hole-transporting Materials Based on Biphenyl Diamine Derivatives with Carbazole Groups

Two hole-transporting materials containing carbazole moieties with TPD- and NPB-like structures, 4,4′-bis [ N- （4-carbazolylphenyl） -N-phenylamino ] biphenyl （ CPB ） and 4,4′-bis [ N- （ 4-carbazolylphenyl ） -N- （ 1-naphthyl ） amino] biphenyl（ CNB）, were synthesized via a modified Ullmann reaction. The resulting compounds were thermally stable with high glass transition temperatures ranging from 145 to 147 ℃ and possessed a good electrochemical reversibility and hole-transporting properties. Typical double-layer device evaluation with the structure ITO/CPB（40 nm）/ Alq3 （60 nm）/LiF/Al demonstrated that they were promising hole-transporting materials with a current efficiency of 5.25 cd/A and a power efficiency of 2.00 lm/W.