Thermal stability of new zinc acetate-based complex compounds

New zinc acetate based complex compounds (of general formula Zn(CH₃COO)₂·1?2L·nH₂O) containing one or two molecules of urea, thiourea, coffeine and phenazone were prepared namely: Zn(CH₃COO)₂·2.5H₂O, Zn(CH₃COO)₂·2u·0.5H₂O, Zn(CH₃COO)₂·tu·0.5H₂O, Zn(CH₃COO)₂·2tu, Zn(CH₃COO)₂·cof·2.5H₂O, Zn(CH₃COO)₂·2cof·3.5H₂O, Zn(CH₃COO)₂·2phen·1.5H₂O. The compounds were characterized by IR spectroscopy, chemical analysis and thermal analysis. Thermal analysis showed that no changes in crystallographic modifications of the compounds take place during (heating in nitrogen before) the thermal decompositions. The temperature interval of the stability of the prepared compounds were determined. It was found that the thermal decomposition of hydrated compounds starts by the release of water molecules. During the thermal decomposition of anhydrous compounds in nitrogen the release of organic ligands take place followed by the decomposition of the acetate anion. Zinc oxide and metallic zinc were found as final products of the thermal decomposition of the zinc acetate based complex compounds studied. Carbon dioxide and acetone were detected in the gaseous products of the decomposition of the compounds if ZnO is formed. Carbon monoxide and acetaldehyde were detected in the gaseous products of the decomposition, if metallic Zn is formed. It is supposed that ZnO and Zn resulting from Zn acetate complex compounds here studied, possess different degree of structural disorder. Annealing takes place by further heating above 600°C.     

The physicochemical and biological properties of zinc(II) complexes

Spectroscopic (IR), thermoanalytical (TG/DTG, DTA) and biological methods were applied to investigate physicochemical and biological properties of seven zinc(II) complex compounds of the following formula Zn(HCOO)₂·2H₂O (I), Zn(HCOO)₂·tph (II), Zn(CH₃COO)₂·2H₂O (III), Zn(CH₃COO)₂·tph (IV), Zn(CH₃COO)₂·2phen (V), Zn(CH₃CH₂COO)₂·2H₂O (VI), Zn(CH₃CH₂CH₂COO)₂·2H₂O (VII), where tph=theophylline, phen=phenazone. The formation of various intermediates during thermal decomposition suggests the dependence on the length of aliphatic carboxylic chain and type of N-donor ligand (tph, phen). The final product of the thermal decomposition was ZnO. The antimicrobial activity of these complexes were tested against G⁺ and G^– bacteria. Strong inhibitive effect was observed towards E. coli, salmonellae and Staph. aureus.     

Study on the equilibrium in the M(CH3COO)2 ? CH3OH ? H2O system (M  Mg2+, Ca2+, Ba2+) at 25°C

The complex formation and dehydration processes in the system M(CH₃COO)₂? CH₃OH? H₂O have been studied by the methods of the physico-chemical analysis at 25°C; (M = Mg²⁺, Ca²⁺ and Ba²⁺). In the Mg(CH₃COO)₂? CH₃OH? H₂O system. methanol was found to behave as a solvent in which complex formation reactions take place, including also methanolation of Mg²⁺. The fields of equilibrium existence of two new compounds have been found: Mg(CH₃COO)₂ · 3H₂O · CH₃OH and Mg(CH₃COO)₂ · 1,5 CH₃OH. In the systems M(CH₃COO)₂? CH₃OH? H₂O (M = Ca²⁺, Ba²⁺), methanol was found to react as a dehydrating reagent.     

Synthesis and characterization of some metal(II) and sodium ions with cyclopentane-1,2,3,4-tetracarboxylate anion

New divalent metal cyclopentane-1,2,3,4-tetracarboxylate (CPTC) hydrates of empirical formula M₂C₅H₆(COO)₄ · nH₂O, where M = Ni, Co, Cu, or Zn and n = 3?6, and sodium CPTC Na₃C₅H₆COOH(COO)₃ · 7H₂O have been prepared and characterized by elemental analysis, magnetic measurements, thermal, and infrared spectral studies. For the sodium salt, a single crystal (Na₃C₅H₆COOH(COO)₃ · 8H₂O) was also obtained. IR spectra of the metal(II) complexes indicate the coordination of metal ions through all carboxylates. For the sodium compound, a band at 1681 cm^?1 indicates that some carboxylic groups have not been deprotonated. The presence of protonated carboxylic group was also confirmed by an X-ray single crystal analysis. On heating in air atmosphere, all complexes lose water molecules and next anhydrous compounds decompose to corresponding metal oxides and sodium carbonate.     

水杨醛苯甲酰腙锰配合物的研究

水杨醛苯甲酰腙C_(14)H_(12)O_2N_2(H_2L)常作为三齿配体和金属离子配位,有两种不同配位形式:HL~-(只失去酚羟基质子)和L~(2-)(进一步失去胺基原子)。本文用以合成了下列两种不同价态锰的配合物:Mn(Ⅱ)(HL)_2和Mn(Ⅲ)(HL)L以及Mn(Ⅱ)(HL)(CH_3COO)·1.5H_2O和Mn(Ⅲ)L(CH_3COO)·0.5H_2O,迄今文献中只见Mn(Ⅱ)L和Mn(Ⅲ)LX(X=CH_3COO~-、Cl~-、Br~-)型双核锰配合物的研究报道。     

Cs2(H3O)Pr(CH3COO)6 und Cs2Pr(CH3COO)5: Synthese,Kristallstrukturen und Thermolyse. Über die analogen Acetate mit Lanthan bis Terbium

Cs₂(H₃O)Pr(CH₃COO)₆ and Cs₂Pr(CH₃COO)₅: Synthesis, Crystal Structures and Thermolysis. Analogous Acetates with Lanthanum through Terbium Single crystals of Cs₂(H₃O)Pr(CH₃COO)₆ are obtained as green plates from an acetic acid solution (≈50%) of Cs₂CO₃ and Pr(CH₃COO)₃ · 1,5 H₂O. The crystal structure monoclinic, Cm, Z = 2, a = 1 540.4(4), b = 691.3(2), c = 1 221.5(4) pm, β = 104.60(5)°, V_m = 379.1(2) cm³/mol, R = 0.040, R_w = 0.035 was determined from four-circle-diffractometer data. The structure consists of monomeric Pr(CH₃COO)₃ units, in which Pr³⁺ is surrounded by nine oxygen atoms. These monomers are linked together to infinite layers parallel (001) by common acetate oxygen atoms with two ?molecules”? of Cs(CH₃COO). Together with an additional acetate ion coordinated to one of the Cs⁺ ions the composition of the layers is [Cs₂Pr(CH₃COO)₆]^?. Between these layers H₃O⁺ is located for electroneutrality. Thermal decomposition of Cs₂(H₃O)Pr(CH₃COO)₆ was examined with thermoanalytical methods (TG/DTA with coupled gas analysis), Guinier-Simon technique and IR spectroscopy: beginning at 70°C the compound looses water and acetic acid. It decomposes topotactically to Cs₂Pr(CH₃COO)₅. At 270°C this acetate decomposes to Cs₂CO₃ and Pr₂O₂CO₃ which emits CO₂ at 600°C form ing Pr₂O₃or PrO_2?x Single crystals of Cs₂Pr(CH₃COO)₅ were obtained from Pr(CH₃COO)₃, in molten Cs(CH₃COO) at about 200°C. The crystal structure tetragonal, P4₃, Z = 4, a = 1 174,5(2), c = 1 480,5(3) pm, V_m = pin,307,5(1) cm³/mol, R = 0,061, R_w= 0,031 again consists of Pr(CH₃COO)₃, monomers where Pr³⁺ has 9 oxygen ligands in its first coordination sphere. They are linked together by two ”molecules“ of cesium acetate to infinite chains along [00l] around the 4, screw axis. There are also acetate bridges between these chains. Isotypic compounds Cs₂(H₃O)M(CH₃COO)₆ and Cs₂M(CH₃COO)₅, and Cs₂M(CH₃COO)₅with M = La? Tb, were obtained from acetic acid solutions or thermal decomposition and were characterized by X-ray Guinier techniques.     

Preparation,identification and thermal properties of (CH3CH2COO)2Zn·2L·H2O (L=thiourea,nicotinamide, caffeine or theorbromine)

Zinc carboxylates complexed with N-donor ligands have potential antifungal effects. The preparation, identification and especially the thermal properties of four hitherto non-characterized compounds of this group of general formula (CH₃CH₂COO)₂Zn·2L·H₂O are described in this paper. The experimental results are confronted with present knowledge on analogous compounds.

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Zusammenfassung Komplexe aus Zinkkarboxylaten mit N-Donorliganden besitzen potentielle fungizide Effekte. Vorliegend werden Herstellung, Identifizierung und insbesondere die thermischen Eigenschaften von vier bislang nicht beschriebenen Verbindungen dieser Gruppe der allgemeinen Formel (CH₃CH₂COO)₂Zn·2L·H₂O beschrieben. Den experimentellen Ergebnissen werden die vorhandenen Kenntnisse über analoge Verbindungen gegenübergestellt.

     

Synthesis,structural characterization and molecular modelling of bidentate azo dye metal complexes: DNA interaction to antimicrobial and anticancer activities

A novel azo dye ligand, namely 1‐[(5‐mercapto‐1H‐1,2,4‐triazole‐3‐yl)diazenyl]naphthalen‐2‐ol (HL), was synthesized. Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺ and UO₂²⁺ complexes were also prepared by the treatment of HL with Mn(CH₃COO)₂?4H₂O, Co(CH₃COO)₂?4H₂O, Ni(CH₃COO)₂?4H₂O, Cu(CH₃COO)₂?H₂O, CuCl₂?2H₂O, Cu(NO₃)₂?6H₂O and UO₂(NO₃)₂?6H₂O. The structures of these metal chelates were confirmed using elemental, spectral, magnetic moment, molar conductance and thermal analyses. The analytical data confirmed the formation of the chelates in 1:1 (metal‐to‐ligand) ratio having the formula [ML(H₂O)X]Y?H₂O, where M is Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺ or UO₂²⁺; X is Cl^?, NO₃^? or CH₃COO^?; and Y is H₂O. The azo compound acts in a monobasic bidentate manner via the nitrogen and oxygen atoms of azo and hydroxyl groups, respectively. All complexes were found to have tetrahedral structures, except the UO₂²⁺ complex that showed octahedral geometry. The mode of interaction between the synthesized complexes and calf thymus DNA was explored by the aid of absorption spectroscopy and viscosity measurements. The azo dye and its chelates were evaluated against the growth of various bacterial and fungal strains (Escherichia coli, Staphylococcus aureus, Aspergillus flavus and Candida albicans) with insight gained into the effect of type of metal centre, type of coordinated anion and position of the metal in the periodic table on the activity of the complexes. The geometric structure of the complexes was optimized using molecular modelling. The in vitro cytotoxicity of the synthesized compounds was tested against HEPG2 cell line.     

Synthesis and characterization of amantadinium iodoacetatobismuthate,a hybrid compound with mixed iodide–carboxylate anions

The amantadinium iodoacetatobismuthate(III) [C₁₀H₁₅NH₃·(CH₃)₂CO]₂[BiI_3.67(CH₃COO)_1.33] is a new hybrid halometallate with iodide ions partially replaced by oxygen-containing acetates to form stronger interaction between the anionic and cationic substructures. The title compound as well-shaped orange-red crystals was synthesized by a facile reaction in acetone solution in the presence of glacial acetic acid. The crystal structure of the compound consists of the infinite anionic chains [BiI_3.67(CH₃COO)_1.33]^2– and the countercations [C₁₀H₁₅NH₃·(CH₃)₂CO]+; according to the optical absorption data, the test compound is a semiconductor with a band gap of 2.06 eV.     

Mechanism of thermal decomposition of cobalt acetate tetrahydrate

The thermal decomposition of cobalt acetate tetrahydrate (Co(CH₃COO)₂ · 4H₂O) has been studied via thermogravimetric (TG) analysis, in situ X-ray powder diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results of TG and XRD showed that the parent salt melted and then the dissolved crystalline water was vaporized in two steps. The dehydration process was followed by a major step concerning the decomposition of the acetate group, leading to basic acetate as an intermediate, which then produced CoO and Co in N₂ and H₂ atmosphere, respectively. Three decomposition intermediates Co(CH₃COO)₂ · 0.5H₂O, Co(CH₃COO)₂, and Co(OH)(CH₃COO) were presumed. In situ XRD experiments revealed that the intermediate basic acetate was poorly crystallized or even amorphous. Evolved gases analysis indicated that the volatile products of acetate decomposition were water vapor, acetic acid, ethylenone, acetone, and CO₂. A detailed thermal decomposition mechanism of Co(CH₃COO)₂ · 4H₂O was discussed.     

Preparation of non-valence compounds of zinc(II) with 1,2- and 1,4-benzenedicarboxylic acids via self-assembly

Nanostructured non-valence compounds based on coordination compounds of zinc(II) with phthalic and terephthalic acids have been prepared. The purity and composition of prepared compounds have been elucidated from X-ray diffraction analysis, IR spectroscopy, elemental analysis, and thermogravimetry studies; thermal decomposition of the non-valence compounds has been studied as well. The prepared self-assembled compounds are co-precipitated with one water molecule and 1.5 acetic acid molecules per unit of the dicarboxylic acid: [Zn₄(OH)₆·o-C₆H₄(COO)₂]·H₂O·1.5CH₃COOH and [Zn₄(OH)₆·p-C₆H₄(COO)₂]·H₂O· 1.5CH₃COOH.     

Synthesis and Crystal Structure of Rubidium Lanthanum Tetraacetate,RbLa(CH3COO)4

The anhydrous rubidium tetraacetato lanthanate, RbLa(CH₃COO)₄, is obtained together with Rb₂La(CH₃COO)₅(H₂O) as colourless single crystals from a 1 : 2 mixture of Rb₂CO₃ and La(CH₃COO) · 1.5 H₂O in acetic acid by slow evaporation. The crystal structure [orthorhombic, Pnnm, Z = 2, a = 1242.0(3), b = 1650.1(4), c = 698.0(4) pm, R = 0.028, R_w = 0.071] contains La³⁺ nine coordinate by oxygen atoms of six acetate ligands. The polyhedra are connected to dimers and further to double chains running parallel to [001]. These [La(CH₃COO)₄]^– double chains are surrounded by four like double chains and connected by Rb⁺ ions that are seven coordinate by oxygen atoms.     

Synthese und Charakterisierung von 2‐O‐funktionalisierten Ethylrhodoximen und ‐cobaloximen

Synthesis and Characterization of 2‐O‐Functionalized Ethylrhodoximes and ‐cobaloximes 2‐Hydroxyethylrhodoxime and ‐cobaloxime complexes L—[M]—CH₂CH₂OH (M = Rh, L = PPh₃, 1 ; M = Co, L = py, 2 ; abbr.: L—[M] = [M(dmgH)₂L] (dmgH₂ = dimethylglyoxime, L = axial base) were obtained by reaction of L—[M]^— (prepared by reduction of L—[M]—Cl with NaBH₄ in methanolic KOH) with BrCH₂CH₂OH. H₂O—[Rh]^—, prepared by reduction of H[RhCl₂(dmgH)₂] with NaBH₄ in methanolic KOH, reacted with BrCH₂CH₂OH followed by addition of pyridine yielding py—[Rh]—CH₂CH₂OH ( 3 ). Complexes 1 and 3 were found to react with (Me₃Si)₂NH forming 2‐(trimethylsilyloxy)ethylrhodoximes L—[Rh]—CH₂CH₂OSiMe₃ (L = PPh₃, 4 ; L = py, 5 ). Treatment of complex 1 with acetic anhydride resulted in formation of the 2‐(acet oxy)ethyl complex Ph₃P—[Rh]—CH₂CH₂OAc ( 6 ). All complexes 1 — 6 were isolated in good yields (55—71 %). Their identities were confirmed by NMR spectroscopic investigations ( 1 — 6 : ¹H, ¹³C; 1 , 4 , 6 : ³¹P) and for [Rh(CH₂CH₂OH)(dmgH)₂(PPh₃)]·CHCl₃·1/2H₂O ( 1 ·CHCl₃·1/2H₂O) and py—[Rh]—CH₂CH₂OSiMe₃ ( 5 ) by X‐ray diffraction analyses, too. In both molecules the rhodium atoms are distorted octahedrally coordinated with triphenylphosphine and the organo ligands (CH₂CH₂OH and CH₂CH₂OSiMe₃, respectively) in mutual trans position. Solutions of 1 in dmf decomposed within several weeks yielding a hydroxyrhodoxime complex “Ph₃P—[Rh]—OH”. X‐ray diffraction analysis exhibited that crystals of this complex have the composition [{Rh(dmg)(dmgH) (H₂O)(PPh₃)}₂]·4dmf ( 7 ) consisting of centrosymmetrical dimers. The rhodium atom is distorted octahedrally coordinated. Axial ligands are PPh₃ and H₂O. One of the two dimethylglyoximato ligands is doubly deprotonated. Thus, only one intramolecular O—H···O hydrogen bridge (O···O 2.447(9)Å) is formed in the equatorial plane. The other two oxygen atoms of dmgH^— and dmg^2—, respectively, act as hydrogen acceptors each forming a strong (intermolecular) O···H′—O′ hydrogen bridge to the H′₂O′ ligand of the other molecule (O···O′ 2.58(2)/2.57(2)Å).     

Photosensitive sol–gel preparation and micro-patterning of (100)-oriented (Ba0.7Sr0.3)TiO3 film on LaNiO3 electrode

Using La(NO₃)₃·nH₂O and Ni(CH₃COO)₂·4H₂O as starting materials, the LaNiO₃ sol was prepared with 2-methoxyethanol as solvent. Using this sol, (001)-oriented LNO films with high conductivity were prepared on LaAlO₃ single crystal substrate by sol–gel method. Using barium acetate, strontium acetate, and Ti(OC₄H₉)₄ as starting materials, acetylacetone and lactic acid as chemical modifiers, photosensitive BST sol was obtained. Using the BST sol, a-oriented BST films were prepared on (001)LNO/LAO. Due to the photosensitivity of the BST sol, the coated BST gel film itself can be used as photoresist. Thus, micro-patterned a-oriented BST films are obtained by exposing, leaching, and annealing the BST gel film. The a-oriented BST film capacitor on LNO/LAO has a high dielectric constant, a low dielectric loss and a low leakage current.     

Synthesis and characterization of new copper(II) complex compounds with chlorhexidine. Part I

Three new copper(II) complex compounds with chlorhexidine diacetate as a ligand have been prepared and characterized by elemental and thermogravimetrical analyses, molar conductances, magnetic susceptibility measurements, infrared, electronic and EPR spectra. The complexes correspond to the formulas: [Cu₂(CHX)Cl₄]·2C₂H₅OH, [Cu₂(CHX)Br₄]·2C₂H₅OH and [Cu₂(CHX)(CH₃COO)₂] (CH₃COO)₂·2C₂H₅OH, where CHX = chlorhexidine, their composition and stereochemistry depending on the reaction conditions and the metal salt used. Chlorhexidine acts as neutral tetradentate NNNN donor, coordinating through the four imine nitrogen atoms. Investigations on antimicrobial activity in vitro show that all the complexes are active against the tested microorganisms, the complex with chloride being more active against Gram negative bacteria than chlorhexidine diacetate..      

Synthesis and Crystal Structure of Copper(II) Trifluoroacetates,Cu2(CF3COO)4 · 2 CH3CN and Cu(CF3COO)2(H2O)4

Cu₂(CF₃COO)₄ · 2 CH₃CN ( I ) and Cu(CF₃COO)₂(H₂O)₄ ( II ) have been prepared by concentrating of acetonitrile and aqueous solutions respectively. According to X-ray data, the complex I consists of binuclear molecules with Cu–O 1.969 Å, Cu–N 2.114 Å. The Cu…Cu distance was found to be 2.766 Å, one of the longest for dimeric structures, apparently, due to the high acidity of trifluoroacetic acid. The coordination environment of Cu atom in II can be described as 4 + 2: 2 Cu–O (H₂O) 1.937 Å, 2 Cu–O (CF₃COO) 1.985 Å, 2 Cu–O (H₂O) 2.447 Å. The mononuclear structure is stabilized by formation of two intra- and six intermolecular hydrogen bonds.     

Synthesis and guest exchange reactions of inclusion compounds of cucurbit[8]uril with nickel(II) and copper(II) complexes

Inclusion compounds of the macrocyclic cavitand cucurbit[8]uril (CB[8]) with the nickel(II) complex, {trans-[Ni(en)₂(H₂O)₂]@CB[8]}Cl₂ · 23.5H₂O, the copper(II) complex, {2[Cu(dien)(bipy)(H₂O)]@CB[8]}(ClO₄)₄ · 11H₂O, and the organic molecules, 2(pyCN)@CB[8]} · 16H₂O and {2(bpe)@CB[8]} · 17H₂O, where bipy is 4,4′-bipyridyl, pyCN is 4-cyanopyridine, and bpe is trans-1,2-bis(4-pyridyl)ethylene, were synthesized. The inclusion compounds with organic molecules were synthesized starting from inclusion compounds of cucurbit[8]uril with cyclam and ethylenediamine complexes of copper(II) and nickel(II) by the guest exchange method, which is based on the replacement of one guest with another in the cavity of the cavitand The resulting compounds were characterized by X-ray diffraction, ESR, ¹H NMR, IR, and electronic absorption spectroscopy, and electrospray mass spectrometry. Photochemically induced [2+2]-cycloaddition of two 1,2-bis(4-pyridyl)ethylene molecules included in cucurbit[8]uril was studied. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 25–34, January, 2006.     

Synthesis of Quantum-Size Cadmium-Zinc Sulfide Particle-Doped Glasses by the Sol-Gel Method

The optical properties of extremely small particles of semiconductor materials provide a sensitive probe of the band structure in the materials. The Sol-Gel process has been applied successfully to the preparation of small particle-size CdS-doped silica glasses such that quantum size effects are significant. Transparent and colorless gels were prepared through the hydrolysis of a complex solution of Si(OC₂H₅)₄, (CH₃)₂SO, Zn(CH₃COO)₂·2H₂O and Cd(CH₃COO)₂·2H₂O. These gels were heated at 350, 500 and 750°C. The thermal treatments of samples were established by TDA/TGA analysis. By means of shift in optical absorption spectra, quantum size effects could be inferred in glasses containing these calcogenide microcrystals.     

Synthese und Kristallstruktur von Praseodympropionat-trihydrat,Pr(CH3CH2COO)3(H2O)3

Synthesis and Crystal Structure of Praseodymium Propionate Trihydrate, Pr(CH₃CH₂COO)₃(H₂O)₃ Single crystals of Pr(CH₃CH₂COO)₃(H₂O)₃ were obtained by dissolving freshly prepared praseodymium hydroxide in diluted propionic acid. The crystal structure (monoclinic, P2₁/c, Z = 4, a = 1034.2(2) pm, b = 1521.2(3) pm, c = 2086.3(7) pm, β = 102.87(2)°, R1 = 0.0864, wR2 = 0.1196) consists of one-dimensional infinite chains parallel [010]. Pr1 and Pr2 are coordinated by four tridentate-bridging propionate groups. Additionally, Pr1 is coordinated by three “coordination water” molecules, Pr2 by two bidentate propionate groups. There are, in addition, three “crystal water” molecules so that praseodymium propionate trihydrate should be formulated as [(H₂O)₃Pr1(CH₃CH₂COO)₄Pr2(CH₃CH₂COO)₂] (H₂O)₃.     

微粒溶胶凝胶法合成锂离子电池用正极材料LiNi0.85Co0.15O2及表征

以LiOH·H₂O、Ni(CH₃COO)₂·4H₂O 和 Co(CH₃COO)₂·4H₂O为原料，在水-乙醇体系中，采用微粒溶胶凝胶方法(PSG)成功地制备了锂离子电池用正极材料LiNi_0.85Co_0.15O₂。使用差热-热重(DTA-TG)方法来研究凝胶的热分解过程。粉末X-射线衍射(XRD)测试表明，在700 ℃、氧气氛中，原料混合物能形成具有较好α-NaFeO₂层状结构的晶型化合物。扫描电镜(SEM)显示，与固相合成方法相比，PSG制备的LiNi_0.85Co_0.15O₂颗粒较细、且颗粒大小分布均匀。充放电实验结果表明，PSG合成的LiNi_0.85Co_0.15O₂首次放电容量为196.4 mAh/g, 10次循环之后，容量还有189.1 mAh/g (3.0～4.3V、18 mA/g)，显示其具有良好的循环性能；而同样条件下，固相法合成的样品，首次放电容量为187.3 mAh/g，10次循环之后，容量衰减为167.1 mAh/g。