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1.
用一种简便快速方法合成了一系列长链有机胺插层V2O5化合物. 用粉末X射线衍射(XRD)、红外光谱(FT-IR)、漫反射紫外-可见光谱(DR UV-VIS)等手段对插层产品的结构进行了表征. 除了正十六胺插层V2O5产品外, 其它长链烷胺插层V2O5产品的层间距d001与长链烷胺碳数n之间具有良好的线性关系: d001=0.160nC+0.731 nm. 正十六胺与V2O5反应后生成两个插层相, 一个相的层间距d001为4.01 nm, 另一相的d001为3.20 nm. 此外, 研究了手性钛的螯合物Ti[(OC2H4)3N][OCH(CH3)2] (记为TEAIP)在V2O5层间的插层行为, 得到相应的插层产品.  相似文献   

2.
采用溶胶凝胶法制备了V2O5-TiO2复合半导体材料,通过Raman、XRD及UV-Vis DRS等实验方法研究了V2O5与TiO2复合对材料表面组成、晶体结构以及光响应性能的影响。结果表明:钒加入后优先与TiO2作用形成较为稳定的金红石型TiVO4晶相,其中V4+是促进TiO2发生相变的关键;随着钒加入量的增加,V2O5由表面高分散状态逐渐聚集形成晶相,并释放部分Ti4+使之形成锐钛矿型TiO2晶相,使得体相中金红石型TiO2的含量有所下降;复合后形成的TiVO4晶相显著提高了材料对可见光的吸收率,并使其吸光域红移至460 nm左右。  相似文献   

3.
固定n(Ce)/n(Zr)比为0.67/0.33,用共沉淀法制得一系列CeO2-ZrO2-Al2O3固溶体.采用这些固溶体作载体,以Fe2O3为活性组分,用浸渍法制备了一系列催化剂.BET结果显示,将适量Ce0.67Zr0.33O2引入到Al2O3载体中有助于催化剂保持较高的比表面积.TPR结果显示,载体中引入适量的Ce0.67Zr0.33O2可以改善催化剂的氧化还原性能.XRD结果表明,Fe2O3在CeO2-ZrO2-Al2O3载体上呈现出良好的分散状况,老化前后催化剂的晶相结构基本无明显变化.特别是当载体中m(Ce0.67Zr0.33O2)∶m(Al2O3)的值为1∶2时,Fe2O3/CeO2-ZrO2-Al2O3催化剂在甲烷催化燃烧中显示出最佳的催化性能和抗高温老化性能.  相似文献   

4.
一些具有NASICON型网格结构的固体电解质具有高的电导率和好的稳定性,NASICON的意思是Na Super Ionic Conductor[1]。当NaZr2(PO4)3中P5 被Si4 部分取代时便可以得到具有NASICON结构的Na1 xZr2SixP3-xO12体系,其具有高的钠离子电导率。然而有相同结构的Li1 xZr2SixP3-xO12体系的离子电导率却很低,这是因为Li 半径太小,而NASICON三维网格结构的离子通道太大,两者不匹配而使电导率下降[2]。但当LiZr2(PO4)3中Zr4 被离子半径小些的Ti4 取代,所得LiTi2(PO4)3的通道就与Li 半径相匹配,适合于锂离子的迁移,从而使其电导率…  相似文献   

5.
通过调节B2O3‐Bi2O3‐ZnO‐Al2O3(BBZA)玻璃的添加量研究其对钛酸钡(BaTiO3)陶瓷烧结条件、晶体结构和介电性能的影响。结果表明:添加适量的BBZA玻璃能够有效地将BaTiO3陶瓷烧结温度由1350℃降至950℃,并使其致密化。同时,添加BBZA玻璃后,BaTiO3的晶体结构随着烧结温度的升高而发生转变(立方相→四方相)。另外,BBZA玻璃的引入使BaTiO3陶瓷的居里峰得到了有效的抑制和拓宽。陶瓷微观形貌显示,玻璃相均匀分布在BaTiO3晶粒表面。优化的BaTiO3陶瓷制备条件如下:BBZA添加量(质量分数)为2.0%,烧结温度为950℃。在该条件下制备的BaTiO3陶瓷介电常数达到1364,介电损耗低至1.2%。  相似文献   

6.
层状Co3O4的制备及其电化学电容行为   总被引:3,自引:0,他引:3       下载免费PDF全文
以P123为模板水热合成制备了Co2(OH)2CO3前驱体,200 ℃热处理后得到了具有层状结构的Co3O4。循环伏安、恒流放电等电化学测试表明,200 ℃所得Co3O4电极在6 mol·L-1 KOH溶液中和-0.1~0.5 V(vs Ag/AgCl)电位范围内,具有较好的循环稳定性能,单电极比电容达到505 F·g-1。  相似文献   

7.
固相法合成的样品,经X-射线粉末衍射(XRD)、扫描电镜(SEM)、红外光谱(FTIR)、电感螯合等离子体发射光谱(ICP-AES)、比表面积(BET)、热重分析(TGA)和滴定法(CT)等表征为α-Ni0.81Al0.19(OH)2.19-2y(CO3)y·xH2O(x=1.1~1.2,y=0.10~0.12)。为了改善其高温性能,样品经混掺不同量Y2O3后作为氢镍电池的正极材料,做了不同温度恒流充放电、微电极循环伏安(CV)和交流阻抗谱(EIS)测定。结果表明,60 ℃时掺Y2O30.4wt%~1.2wt%,能提高样品不同倍率放电比容量达18.1%~42.0%,同时也改善了高温放电电位。  相似文献   

8.
利用类石墨氮化碳(g-C3N4)和亚稳相钙钛氧化物(CaTi2O5)固相法制备C3N4/CaTi2O5复合材料。利用X射线衍射(XRD)、金相显微镜、扫描电子显微镜(SEM)及附带能谱分析仪(EDS)和N2吸附-脱附对样品的显微结构和比表面积进行检测分析,并用紫外-可见吸收光度计(UV-Vis)测试了样品的光吸收性能,研究C3N4与CaTi2O5物质的量之比(nC3N4/nCaTi2O5)对C3N4/CaTi2O5复合样品的物相结构和微观形貌的影响,同时考察C3N4/CaTi2O5复合样品在可见光照射下光催化降解罗丹明染料效果。实验结果表明:相比纯C3N4和CaTi2O5样品,C3N4/CaTi2O5复合样品在可见光下具有较高的光催化性能,随着nC3N4/nCaTi2O5增加,样品的光催化降解率随之增加而后降低,当nC3N4/nCaTi2O5=1:1时,样品的光催化降解率达到最大值99.5%,并且循环重复利用5次后,样品的光催化剂降解率仍几乎保持不变。复合样品光催化性能提高主要归因于复合能级结构有效地抑制了电子和空穴复合所致。  相似文献   

9.
刘荣梅  马桂林  周丽  陈蓉 《化学学报》2005,63(6):491-496
以湿化学法制得Zr(OH)4和Sm(OH)3的共沉淀为前驱体, 在碱性介质中用水热法合成了(ZrO2)0.86(Sm2O3)0.14及(ZrO2)0.88(Sm2O3)0.12纳米粉体. 将纳米粉体在较低温度(1450 ℃)下烧结制得了致密的固体电解质陶瓷样品, 比通常高温固相反应法采用的烧结温度(>1600 ℃)降低了150 ℃以上. XRD测定结果表明, (ZrO2)0.86(Sm2O3)0.14纳米粉体及其烧结体均为立方相, 但(ZrO2)0.88(Sm2O3)0.12纳米粉体为立方相, 它的烧结体为立方相和单斜相的混合相. 用交流阻抗谱法、氧浓差电池法及氧泵(氧的电化学透过)法研究了(ZrO2)0.86(Sm2O3)0.14陶瓷样品在600~1000 ℃下的离子导电特性. 结果表明, 该陶瓷样品在600~1000 ℃下氧离子迁移数为1, 氧离子电导率的最大值为3.2×10-2 S•cm-1, 是一个优良的氧离子导体; 它的氧泵性能明显地优于YSZ.  相似文献   

10.
采用水热法制备了Na_3V_2(PO_4)_2O_2F (NVPOF)钠离子电池正极材料,利用X射线衍射(XRD)、扫描电子显微镜(SEM)和恒流充放电(GCD)等方法研究了其形貌、结构与电化学性能。结果显示,纯相NVPOF形貌规则,呈长1~3μm、宽300 nm~1μm、长宽比为2~3的四棱柱形貌。NVPOF具有2对平稳的充放电平台,在0.2C和2C电流密度下,放电比容量达到124.2和70.5 m Ah·g~(-1),经100次循环后,放电比容量仍有105.8和59.6 m Ah·g~(-1),容量保持率达到85.2%和84.5%,库仑效率基本在97%以上,且低温(0℃)电化学性能也有不错的表现。经还原氧化石墨烯(r GO)包覆提高电子电导率,NVPOF@r GO在0.5C和2C的室温放电比容量高达124.4和88.4 m Ah·g~(-1),且2C倍率下循环200圈后的比容量仍有78.7 m Ah·g~(-1),容量保持率高达89%,库仑效率始终保持在99%左右,显示出优异的倍率和循环性能。  相似文献   

11.
A novel heteropoly compound, containing two kinds of coordinated cations, [K(H2O)2Ni(H2O)6]2[V10O28], has been synthesized through routine process and characterized by elemental analyses, IR, 51V NMR and single crystal X-ray diffraction. It crystallizes in the triclinic system, space group P1 with a=0.87382(17) nm, b=1.075 4(2) nm, c=1.111 1(2) nm, α=65.10(3)°, β=75.01(3)°, γ=70.63(3)°, V=0.884 8(3) nm3 and Z=1. The X-ray analysis reveals that the two kinds of coordinated cations are linked by three shared coordinated water molecules, and K+ cations coordinate with ten oxygen atoms: five of which come from V10O286- anion, the other five from water molecules. The title compound exhibits extended 2D array building up of V10O286- groups connected by ten-coordinated K+ cations. The hexahydrated nickel cations Ni(H2O)62+ lie in neat apposition to three adjacent V10O286- clusters. CSD: 413271.  相似文献   

12.
Hexanuclear oxo titanium(IV) siloxo carboxylate complexes with the general formula [Ti6O6(OSi(CH3)3)6(OOCR)6] (R = But (1), CH2But (2), C(CH3)2Et (3)) were synthesized in quantitative yield, by the reaction of Ti(OSiMe3)4 with the appropriate organic acid. Crystal structure determination revealed that molecules of 13 are composed of [Ti6-(μ3-O)6] cores stabilized by six synsyn carboxylato bridges and six terminal siloxide ligands. Each metal atom is surrounded by six oxo atoms, capping the triangular faces of the distorted octahedron. Spectral characterization (IR, NMR) of 13 revealed a significant non-equivalence of the carboxylate group interactions, resulting from the asymmetry of the Ti-μ-OOC bonds of the synsyn bridges. The thermal stability of the studied compounds was determined from TGA/DTA analysis.  相似文献   

13.
A new layered aluminophosphate, denoted AlPO-CJ12, has been synthesized in the system Al(OPri)3-H3PO4-tetramethylethylenediamine-triethyleneglycol and its structure solved by single-crystal X-ray diffraction analysis. It is further characterized by X-ray powder diffraction, ICP, TG, DTA, and elemental analyses. The compound has an empirical formula of [Al3P4O16][(CH3)2NHCH2CH2NH(CH3)2][H3O], and crystallizes in the triclinic space group P-1 (No. 2) with a=8.9907(6) Å b=9.8359(6) Å, c=14.5566(8) Å, α=75.872(3)°, β=88.616(3)°, γ=63.404(3)°, Z=2, R1=0.0451, and wR2=0.1094. The alternation of tetrahedral AlO4 and PO3 (=O) units forms a sheet structure with a 4×6×8 network. The inorganic layers stacked in an AAAA sequence are held together by the protonated organic amine and water molecules. The co-templating role of the water molecules is studied by the calculation of the nonbonding host-guest interaction energies through a computational simulation.  相似文献   

14.
The title complex Cu[C5H3N(CCH3=N-C6H5)2]2(PF6)2 has been synthesized by reaction of Schiff base C5H3N(CCH3=N-C6H5)2 and cupric sulfate in toluene solution. The crystal structure was determined by X-ray diffraction method and the chemical formula weight of the complex is 1041.85. The crystal structure belongs to triclinic system with space group P1 and cell parameters: a=12.6470(10)?, b=14.123(2)?, c=15.613(2)?;α=66.150(10)°,β=79.470(10)°,γ=78.290(10)°, V=2481.6(5)?3, Z=2, Dc=1.394Mg·m-3 and F(000)=1064. The final R[I >2σ(I)]:R1=0.0668, wR2=0.1927; R(all data): R1=0.1133, wR2=0.2357. The Cu(Ⅱ) was coordinated by six nitrogen, at the same time the Cu(Ⅱ) formed a distorted octahedron, besides the angles and planes of this compound were discussed . The result of kinetics of the thermal decomposition indicated that the first step of it is 2 series chemical reactions, the function of machanism is f(a)=(1-a)2, and the activation energy is 144.64E/kJ. CCDC: 180872.  相似文献   

15.
A novel nickel(Ⅱ) complex with 2,4-dihydroxybenzalidene benzoylhydrazone and pyridine ligands, Ni(C14H10N2O3)(C5H5N), has been synthesized and characterized by elemental analysis and IR. The crystal structure of the title complex has been determined by single crystal X-ray diffraction techniques. The crystal belongs to orthorhombic, space group Pbca. The cell parameters are: a=1.580 20(19) nm, b=1.362 18(16) nm, c=1.616 50(19) nm, and V=3.479 5(7) nm3, Z=8, Dc=1.497 Mg·m-3, μ(Mo)=1.139 mm-1, F(000)=1 616, R=0.032 9 and wR=0.077 0 for 2 772 observed reflections (I>2σ(I)) out of 3810 unique ones. The nickel(Ⅱ) ion lies in a distorted square-planar environment composed of two oxygen atoms, one nitrogen atom of tridentate acyhydrazone schiff base ligand and one nitrogen atom of the pyridine ligand. The analysis of the crystal structure indicates that the complex has a one-dimensional chain structure, which is formed by intermolecular hydrogen bonds. CCDC: 244668.  相似文献   

16.
The crystal structures of the Rh[(EtO)2PS2]3 (I) and Co[(PhO)2PS2]3 (II) chelate compounds were determined from X-ray diffraction (XRD) data (CAD-4 diffractometer, MoK β radiation, 1193 F hkl , R = 0.0516 for I and 513 F hkl , R = 0.0305 for II). Crystals I are monoclinic: a = 14.233(3) Å, b = 13.570(3) Å, c = 14.272(3) Å; β = 90.66(3)°, V = 2756.3(10) Å3, Z = 4, ρcalc = 1.587 g/cm3, space group C2/c. Crystals II are trigonal: a = 15.149(2) Å, c = 30.306(6) Å; V = 6023.2(16) Å3, Z = 6, ρcalc = 1.493 g/cm3, space group R3ˉ. Structures I and II consist of discrete mononuclear molecules. The coordination polyhedra of the M atoms (M = Rh, Co) are distorted octahedra formed by six sulfur atoms of three cyclic bidentate (RO)2 PS2 ligands. Original Russian Text Copyright ? 2008 by R. F. Klevtsova, L. A. Glinskaya, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 2, pp. 330–334, March–April, 2008.  相似文献   

17.
The title compound {[(p-MeC6H4CH2)2Sn]2(O)(Cl)OC2H5}2 was synthesized by the reaction of bis(p-met-hylbenzyl)tin dichloride with KOH in ethanol. The crystal structure of the complex has been determined by X- ray diffraction. The crystal belongs to monoclinic, space group P21/c with a=1.114 0(19) nm, b=2.423 1(3) nm, c=2.521 1(3) nm, β=99.398(3)°, V=6.714(16) nm3, Z=4, Dc=1.493 g·cm-3, μ(Mo Kα)=15.94 cm-1, F(000)=3 024, R1=0.049 9, wR=0.101 7. The crystal structure shows that the coordination geometry of tin is a distorted trigonal bipyramid, and the ladder-like structure is shaped by three Sn2O2 planar four-membered rings. CCDC: 639682.  相似文献   

18.
The IR and Raman spectra of [(CH3)3NH]3Sb2Cl9 (A), [(CH3)3NH]3Bi2Cl9 (B) and two of their mixed crystals containing respectively 33% (AB.33) and 42% Bi (AB.42) are analyzed and compared. A and AB.33 show ferroelectric–paraelectric phase transition at 364 K and 344 K, respectively. AB.42 and B are paraelectric in the temperature range between 90 and 365 K. Most of the vibrational modes show continuous changes, with the temperature, in the IR frequencies or intensities with no soft mode behavior. However, characteristic ν(NHCl) and δ(NHCl) vibrations of weakly hydrogen-bonded species are only observed in A and AB.33 below the temperature of the phase transition and are related to the ferroelectricity. The evolution of the IR spectra with the temperature suggests that the ferroelectric properties are connected with the reorientation of the cations which needs a breaking of the weak NHCl hydrogen bonds in the paraelectric phase.  相似文献   

19.
Reactions of R2SnO (R: nBu, Cy, Ph, PhCH2) and R3SnCl (R: Ph, Cy, PhCH2, 2-Cl-PhCH2, 4-F-PhCH2, 4-Cl-PhCH2) with N-(4-carboxyphenyl)-salicylideneimine (LH2) in 1:1 stoichiometry afford complexes {[R2Sn(LH)]2O}2 and R3Sn(LH). These complexes have been characterized by elemental analyses, IR, 1H and 119Sn NMR spectroscopy. The crystal structures of {[nBu2Sn(LH)]2O}2, 1 and Ph3Sn(L), 5 are determined by single crystal X-ray diffraction. Results showed that in the solid state the complex 1 is a tetranuclear centrosymmetric dimer with six-coordination being assigned to both the endo-cyclic and exo-cyclic tin atoms after consideration of close intermolecular tin oxygen contacts, and study show that the imino nitrogen atom do not participate in coordination to the tin atom. The complex 5 is a monomer, and in the molecule the tin atoms are five-coordinated in trigonal bipyramidal geometries with the two oxygen atom of the carboxylate both coordinating to the tin atoms.  相似文献   

20.
The novel seven-coordinate complex [(n-Bu)2Sn(C10H8N2O3)(C2H5OH)]2 (C10H8N2O32- is the dinegative ion of 2-oxo-propionic acid benzoyl hydrazone) was synthesized by the reaction of (n-Bu)2SnO with 2-oxo-propionic acid benzoyl hydrazone in 1∶1 molar ratio in benzene-ethanol (V/V, 3/1), and its structure was characterized by X-ray single crystal diffraction. The crystal belongs to a tetragonal system with space group I41/a, a=2.4890(2)nm, b=2.4890(2)nm, c=1.5170(3)nm, V=9.398(2)nm3, Z=8, F(000)=3968, Dc=1.366g·cm-3, and the structure was refined to final R1=0.0530, wR2=0.0971. The structure of the title complex is described as a dimer through weak interactions of Sn…O bonding and hydrogen bond. The tin atoms rendered sev-en-coordination in a distorted pentagonal bipyramid geometry structure, four oxygen atoms [O1, O2, O2#1 and O4] and one nitrogen atom N2 formed the equatorial plane and C11-Sn1-C15 is the axis. CCDC: 212696.  相似文献   

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