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1.
采用水热、化学沉积和原位光还原的方法成功制备了新型Ag/Ag2MoO4/Bi2MoO6三元复合光催化剂。通过X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)和紫外可见漫反射光谱(UV-Vis DRS)等技术对材料的组成、形貌、光吸收特性和光电化学性能等进行系统分析。以四环素为目标污染物,研究Ag/Ag2MoO4/Bi2MoO6在可见光下的光催化性能。研究结果表明,相比于纯Ag2MoO4和Bi2MoO6,Ag的表面等离子体共振(SPR)效应显著拓宽了催化体系对可见光的吸收能力及响应范围。当Ag2MoO4理论负载量(质量分数)为24.6%时,Ag/Ag2MoO4/Bi2MoO6复合材料在20 min内可将四环素完全降解,且5次循环使用后仍保持较高的催化活性,表现出良好的循环稳定性。  相似文献   

2.
采用水热、化学沉积和原位光还原的方法成功制备了新型Ag/Ag2MoO4/Bi2MoO6三元复合光催化剂。通过X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)和紫外可见漫反射光谱(UV-Vis DRS)等技术对材料的组成、形貌、光吸收特性和光电化学性能等进行系统分析。以四环素为目标污染物,研究Ag/Ag2MoO4/Bi2MoO6在可见光下的光催化性能。研究结果表明,相比于纯Ag2MoO4和Bi2MoO6,Ag的表面等离子体共振(SPR)效应显著拓宽了催化体系对可见光的吸收能力及响应范围。当Ag2MoO4理论负载量(质量分数)为24.6%时,Ag/Ag2MoO4/Bi2MoO6复合材料在20 min内可将四环素完全降解,且5次循环使用后仍保持较高的催化活性,表现出良好的循环稳定性。  相似文献   

3.
Single crystals of Cs4[(UO2)2(C2O4)(SO4)2(NCS)2] · 4H2O (I) and (NH4)4[(UO2)2(C2O4)(SO4)2(NCS)2] · 6H2O (II) have been synthesized and studied by X-ray diffraction. The crystals of both compounds are orthorhombic with the space group Pbam, Z = 2, and unit cell parameters a = 12.0177(3) ?, b = 18.6182(5) ?, c = 6.7573(10) ?, R = 0.0376 (I); a = 11.6539(9) ?, b = 18.3791(13) ?, c = 6.7216(5) ?, R = 0.0179 (II). The main structural units of crystals I and II are [(UO2)2(C2O4)(SO4)2(NCS)2]4− chains belonging to the crystal-chemical group A2K02B22M21 (A = UO22+, K02 = C2O42−, B2 = SO42−, M1 = NCS) of the uranyl complexes. The uranium-containing chains are joined into a three-dimensional framework due to a system of electrostatic interactions with the cesium or ammonium ions in the structure of I. In the structure of II, this framework is additionally stabilized by hydrogen bonds involving the outer-sphere water molecules and ammonium ions. Original Russian Text ? I.V. Medrish, A.V. Virovets, E.V. Peresypkina, L.B. Serezhkina, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 7, pp. 1115–1120.  相似文献   

4.
Solubility in the Li2MoO4-(NH4)2MoO4-H2O system at 25°C was studied. A congruently saturating double molybdate crystal hydrate LiNH4MoO4 · H2O was found to form in the system. The density, refractive index, viscosity, surface tension, and specific electrical conductivity were measured for saturated aqueous solutions of the system. Molar volume, ionic strength, and equivalent conductivity isotherms were calculated. A correlation is observed between the variations of these properties of solutions and solubility in the system. The double salt was recovered and characterized by chemical analysis, IR spectroscopy, and dynamic and quasi-equilibrium thermogravimetry. A thermolysis scheme is suggested proceeding from the thermal curves and chemical analysis of intermediate phases.  相似文献   

5.
Reaction of tin tetrachloride with the appropriate Grignard reagent gave Sn[C6H4-CH(OCH2)2]4 (2), which was transformed to Sn[C6H4-CHO]4 (3) and its hydrazido and amino derivatives Sn[C6H4-CHN-NH-C6H3-2,4-(NO2)2]4 (5) and Sn{C6H4-CH[N(C2H4)2O]2}4 (8). Oxidation of (3) produced Sn[C6H4-COOH]4 (4) while reduction of (3) gave Sn[C6H4-CH2-OH]4 (6). From the acid 4, an amino acid Sn[C6H4-CO-NH-CH2-CO-OCH3]4 (7) could be obtained by reaction with the methyl ester of glycine. All compounds were isolated in pure form with yields of 40-64% and were characterised by spectroscopic means (heteronuclear NMR) or by X-ray structure determination (3).  相似文献   

6.
The novel 3D coordination polymer {Cd2(C4H2O4)2(C4H6N2)2(H2O)2 · 2H2O} n (I) has been synthesized and characterized by standard solid state methods including single-crystal X-ray crystallography. The compound crystallizes in triclinic space group P [`1]\bar 1 with a = 8.589(4), b = 10.585(3), c = 13.094(1) ?, α = 84.91(4)°, β = 79.21(0)°, γ = 83.76(4)°, V = 1159.5(1) ?3, Z = 2. The fumaric acid acts as a multimodal bridging ligand in the polymer unit. One of the fumaric acid ligands tridentately chelates to two Cd2+ cations in the same dinuclear unit, while the other bidentately chelates to two Cd2+ cations in another dinuclear unit. The two metal centers possess slightly distorted pentagonal bipyramid geometry with four Cd {(μ4-fumarato)-(μ2-fumarato)-bis(2-methylimidazolyl)-diaqua} units joining together to form a 28-membered ring. The whole molecule exhibits a through channel along y-axis and 2D layers in xz plane. With hydrogen bond and π-π interaction, the 2D layers construct a 3D microporous network.  相似文献   

7.
用液相反应-前驱物烧结法制备了Cr2(WO4)3和Cr2(MoO4)3粉体。298~1 073 K的原位粉末X射线衍射数据表明Cr2(WO4)3和Cr2(MoO4)3的晶胞体积随温度的升高而增大, 本征线热膨胀系数分别为(1.274±0.003)×10-6 K-1和(1.612±0.003)×10-6 K-1。用热膨胀仪研究了Cr2(WO4)3和Cr2(MoO4)3在静态空气中298~1 073 K范围内热膨胀行为,即开始表现为正热膨胀,随后在相转变点达到最大值,最后表现为负热膨胀,其负热膨胀系数分别为(-7.033±0.014)×10-6 K-1和(-9.282±0.019)×10-6 K-1。  相似文献   

8.
The title compound was synthesized by reaction of Cu(ClO4)2, picolinic acid and carbamide in C2H5OH/CH3CN solution, and characterized by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pbca with a=14.0481(8), b=9.0130(5), c=18.626(1)?, V=2358.3(2)?3Z=4, Dx=1.771g·cm-3, μ=1.235mm-1 and F(000)=1276. The final R factor is 0.0440 for 1434 observed reflections. The X-ray analysis revealed that the copper(Ⅱ) atom is coordinated by two picolinic ligands in the equatorial plane, while the two oxygen atoms of perchlorate occupy the axial positions of octahedron with lengthened Cu-O distances, resulting in a 4+2 elongated octahedral environment. In the compound, there also exist two protonated carbamide cations for charge balance. CCDC: 195354.  相似文献   

9.
Three novel 1:2 composite compounds prepared with the isopolyanions and lanthanide-organic units, (NH4)2{[Ln2(HL)2(H2O)9][(H2W12O40)]}·nH2O (Ln = Gd3+ (1), Tb3+ (2), n = 15; Ho3+ (3), n = 10; L = pyridine-3,5-dicarboxylate) were synthesized at room temperature and characterized by routine methods. X-ray structural analysis reveals that these structures are isomorphic: two crystallographically independent Ln3+ ions (Ln1 and Ln2) locate in different coordination environments; two ligands plays dissimilar coordination mode; the isopolyanion cluster acts as a tridentate ligand and connects three Ln3+ ions (Ln1, Ln1′ and Ln2) forming an unusual 2D undee-layer. The room temperature luminescent of 2 has been studied and exhibits a Tb3+ characteristic emission in the range of 450–650 nm.  相似文献   

10.
By the reaction of [Mo3S4(C2O4)3(H2O)3]2− with PdCl2 and NH4H2PO2 as a reducing agent, followed by the addition of PPh3, a new oxalate cuboidal cluster complex [Mo3(PdPPh3)S4(C2O4)3(H2O)3]2− is obtained. It was isolated and structurally characterized as K2[Mo3(PdPPh3)S4(C2O4)3(H2O)3]·0.5H2O. Original Russian Text Copyright ? 2008 by A. L. Gushchin, M. N. Sokolov, D. Yu. Naumov, and V. P. Fedin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 4, pp. 775–778, May–June, 2008.  相似文献   

11.
 Oxo peroxo glycolato complexes of vanadium(V) (M 2[V2O2(O2)2(C2H2O3)2nH2O (n=0, 1; M=NBu4 + (1), K+ (2), NH4 + (3), Cs+ (4), NPr4 + (5)) as well as (NBu4)2[V2O4(C2H2O3)2]ċ H2O (6) have been prepared and characterized by spectroscopic methods. X-Ray structure analysis of 1 revealed the presence of dinuclear [V2O2(O2)2(C2H2O3)2]2− anions with a (chemical structure) bridging core and six coordinated vanadium(V) atoms in a distorted pentagonal pyramidal array.  相似文献   

12.
Thermodynamical data of rare earth complexes with amino acid are important for engineering chemistry and fundamental chemistry. However, they have rarely been reported. In this work, a series of crystalline complexes of rare earth perchlorate coordinated with glutamic acid have been synthesized in water medium, and their thermodynamical data, including the heat capacity in low temperature range and the standard enthalpy of formation, were determined. These complexes were identified to be [RE2(Glu)2(H2O)8](ClO4)4·H2O (RE = Nd, Eu, Dy) by using thermogravimetric analysis (TG), differential thermal analysis (DTA), and chemical and elementary analyses. Their purity has been determined. No melting points were observed for all the three complexes. The heat capacity of the complexes was measured by an adiabatic calorimeter from 79 to 370 K. Abnormal heat capacity values were detected for two of the complexes and the decomposition range of one complex was found. The temperature, enthalpy change and entropy change of the decomposition processes of the three complexes were calculated. The polynomial equations of heat capacity in the experimental temperature range have been obtained by least squares fitting. The standard enthalpy of formation was determined by an isoperibol reaction calorimeter at 298.15 K. Supported by the Research Fund of Beijing Institute of Petro-Chemical Technology (N06-06)  相似文献   

13.
以五水硝酸铋为铋源,采用简易的一步水热法合成出Bi_2MoO_6/CoMoO_4绣花球结构。通过X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶红外光谱(FT-IR)、紫外-可见漫反射光谱(UV-Vis DRS)、荧光光谱(PL)和电化学测试等表征对所制备催化剂的物相组成、微观形貌、光学性质以及光生电荷复合效率进行了分析。研究结果表明,引入Bi_2MoO_6之后,Bi_2MoO_6/CoMoO_4复合异质结的光吸收范围明显被拓宽,其光生电荷的分离率也得到了提升。以亚甲基蓝和头孢曲松钠为污染物来模拟废水,在可见光的条件下评估催化剂样品的光催化降解活性。在可见光下光照60 min后,Bi_2MoO_6负载量为30%(w/w)的复合物具有最佳的光催化性能,其降解速率常数约为纯CoMoO_4的2倍。基于实验的所有表征,进一步地研究了Bi_2MoO_6/CoMoO_4体系相应的光催化机理。  相似文献   

14.
[Mn2(CHZ)4(H2O)2](PA)4·10H2O的制备和分子结构研究   总被引:10,自引:0,他引:10  
本文论述了苦味酸(PA,三硝基苯酚)锰与碳酰肼(CHZ, NH2NHCONHNH2)反应制备目标配合物的方法及该配合物的晶体结构。该配合物的结构式为[O,O′-μ-Mn2(CHZ)4(H2O2)](PA)4·10H2O。晶体属三斜晶系,P1 空间群。晶体学参数为:a=0.8269(1) nm, b=1.2812(1) nm, c=1.5915(1) nm; α=109.58(1)°, β=95.19(1)°, γ=92.76(1)°, V=1.5765(2)nm3; Z=1, Dc=1.580 g·cm-3, μ(Mo Kα)=520 m-1。晶体结构经全矩阵最小二乘法修正,最终偏离因子R=0.0557。该化合物为具有中心对称的双核配合物,以两个碳酰肼分子中羰基氧为桥原子将两个锰离子结合起来,与锰离子形成配位键的原子是碳酰肼分子第一、五氮原子,羰基氧原子和水分子中的氧原子,锰离子的配位数为七。若味酸根作为外界离子以库伦力和氢键与内界离子结合成配合物分子。  相似文献   

15.
采用一步水热法制备Bi2MoO6/BiVO4复合光催化剂. 利用X 射线衍射(XRD)、场发射扫描电子显微镜(FESEM)、高分辨透射电子显微镜(HRTEM)等手段对其晶体结构和微观结构进行了表征. 结果表明, Bi2MoO6纳米粒子沉积在BiVO4纳米片表面从而形成异质结结构. 紫外-可见漫反射光谱(UV-Vis DRS)表明所制备的Bi2MoO6/BiVO4异质结较纯相Bi2MoO6和BiVO4对可见光吸收更强. 由于形成异质结结构及其光吸收性能使Bi2MoO6/BiVO4 光催化活性有较大提高. 可见光下(λ>420 nm)光催化降解罗丹明B (RhB)实验结果表明,Bi2MoO6/BiVO4光催化活性较纯相Bi2MoO6和BiVO4高. Bi2MoO6/BiVO4样品光催化性能提高的原因是Bi2MoO6和BiVO4形成异质结, 从而有效抑制光生电子-空穴对的复合, 增大了可见光吸收范围及比表面积.  相似文献   

16.
四核铁配合物[Fe4(NTB)42-O)24-Suc)](ClO4)6与DNA具有较强的结合作用,结合常数kb达(5.9±0.4)×105 L·mol-1。该多核铁配合物由水解途径促进DNA断裂,在酸性及低离子浓度条件下的促进作用较为显著。动力学分析表明DNA水解没有明显的序列选择性,质粒DNA从超螺旋转变为切口形式符合饱和酶动力学规律,饱和速率常数ksat=0.014 min-1。  相似文献   

17.
Preparation of the following new m-SF5CF2CF2C6H4X derivatives has been achieved: X=N3(2), Br(3), OC(O)CHCH2(4), CHCH2(5). The compounds were characterized by their respective IR, NMR, mass spectra (MS) and high resolution mass spectrometry (HRMS). An improved yield of SF5(CF2)2C6H5 (1) is also reported along with the synthesis of the polyacrylate (6) and polystyrene (7) from their respective monomers.  相似文献   

18.
利用微波技术合成了配合物[Gd2(Gly)6(H2O)4](ClO4)6(H2O)5, 进行了化学成分分析、红外表征和热重分析. 应用X衍射仪测定其晶体结构, 该晶体为一维链结构, 属三斜晶系, P 空间群, 晶胞参数: a=1.1569(17) nm, b=1.4138(2) nm, c=1.5642(2) nm, α=96.910(2)°, β=102.735(2)°, γ=105.512(2)°, V=2.3606(6) nm3, Z=2, Dc=2.144 g•cm-3. 采用精密溶解-反应量热计, 通过设计热化学循环, 计算出了该配合物的标准摩尔生成焓为 -(7960.73±3.23) kJ•mol-1.  相似文献   

19.
配合物Fe(pda)2(H2O)4和[FeCo(pda)4(H2O)4]n的合成与晶体结构   总被引:1,自引:0,他引:1  
采用水热法合成了2个3-(3-吡啶基)丙烯酸的配合物:Fe(pda)2(H2O)4(1)和[FeCo(pda)4(H2O)4]n(2)(pda=3-(3-吡啶基)丙烯酸),用红外光谱、元素分析、热重-差热以及X-射线衍射单晶结构分析进行了表征.2个配合物都属于单斜晶系,配合物1的空间群为P21/n,配合物2的为P21/c.配合物1是一个pda配体中仅吡啶基氮原子参与配位、而羧基上的氧原子未参与配位的单核结构,通过大量的氢键作用形成三维超分子体系.2是pda配体桥联Fe和Co的异核二维层状配位聚合物;配体吡啶基上的氮原子和羧基上的氧原子都参与了配位,其中羧基采用单齿配位模式.  相似文献   

20.
采用从头计算MP2和CIS方法分别优化等电子双核d8配合物[Pt2(P2O4H2)4]4-和[Pt2(P2O4CH4)4]4-的基态和激发态结构。结果表明基态Pt-Pt距离分别为0.290 5和0.298 7 nm,与实验的0.292 5和0.298 0 nm符合。NBO计算的Pt-Pt键级以及Pt原子间伸缩振动说明Pt-Pt相互作用具有吸引本质。CIS计算揭示电子激发到Pt-Pt的σ(pz)成键轨道使得相互作用增强。保持激发态几何,含时密度泛函理论(TD-DFT)计算的溶液发射分别为449和475 nm,与实验值512和510 nm接近。  相似文献   

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