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1.
龚文朋  陈丹  杨水金 《应用化学》2017,34(11):1321-1328
以2-氨基对苯二甲酸、4,4'-联吡啶配体和硝酸铜为原料,在溶剂热的条件下,合成了一种的阴离子型三维金属有机框架(MOF)材料Cu(BDC-NH_2)(4,4'-Bipy)_(0.5)(BDC=对苯二甲酸根,Bipy=联吡啶)。通过IR、XRD、SEM、TG、N_2吸附法测比表面积等技术手段表征材料的结构和性能。研究了Cu(BDC-NH_2)(4,4'-Bipy)_(0.5)材料对甲基紫的吸附性能,探讨了甲基紫溶液的初始p H值和初始浓度以及不同吸附温度对吸附量的影响。结果表明,等温吸附模型符合Langmuir等温吸附模型,动力学符合拟二级动力学。热力学参数ΔG0、ΔΗ0和ΔS0,表明Cu(BDC-NH_2)(4,4'-Bipy)_(0.5)对甲基紫的吸附是自发和放热的,在溶液p H=9,温度为20℃条件下,Cu(BDC-NH_2)(4,4'-Bipy)_(0.5)对甲基紫的吸附量为60.09 mg/g,说明Cu(BDC)(4,4'-Bipy)_(0.5)材料可以通过氨基改性,提高其对染料的吸附能力。  相似文献   

2.
采用聚苯乙烯(PS)微球做模板,以甲醇真空法制备的三维有序大孔材料(3DOM)TiO_2为载体,通过浸渍法将其与多酸H_6P_2W_(18)O_(62)复合制备成3DOM H_6P_2W_(18)O_(62)/TiO_2。通过傅立叶-红外光谱(FT-IR)、X射线粉末衍射(XRD)、紫外-可见漫反射吸收光谱(UV-Vis/DRS)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)和N2吸附-脱附等表征手段对所合成材料的光吸收性质、结构和晶相进行了表征,结果表明,3DOM H_6P_2W_(18)O_(62)/TiO_2复合材料中多酸仍然保留其Dawson结构,且晶型结构以TiO_2锐钛矿结构为主。为考察所合成纳米复合材料3DOM H_6P_2W_(18)O_(62)/TiO_2的光催化活性,选用甲基橙为模型分子,在紫外光、可见光和微波辅射等多模式作用下,对其进行了光催化活性的研究。结果显示,紫外光催化过程中纳米复合材料3DOM H_6P_2W_(18)O_(62)/TiO_2的活性最高,且在可见光、微波作用下3DOM H_6P_2W_(18)O_(62)/TiO_2对染料均具有一定的降解效果。  相似文献   

3.
本文在测定了五个新颖双核钼(Ⅴ)簇合物的晶体结构(QH)_4[Mo_2O_4(NCS)_6](1),H(PyH)_3·[Mo_2O_4(C_2O_4)_2(H_2O)_2]_2·2H_2O(2),(QH)_3[Mo_2O_4(C_4H_3OCOO)(NCS)_4](3),(QH)_3[Mo_2O_4·(CH_3OH)(NCS)_5](4)和(PyH)_4[Mo_2O_3(SO_4)(NCS)_6](5)以及文献报道该类型化合物结构数据的基础上,综述了含氧桥双核钼(Ⅴ)簇合物的结构特征,并应用SCC-EHMO方法探讨了该类型化合物的电子结构和成簇机理,最后用简正坐标分析法,研究了含氧桥双核钼(Ⅴ)化合物簇胳单元[Mo_2O_4]~(2 )和[Mo_2O_3SO_4]~(2 )的振动结构及其红外谱带归属。  相似文献   

4.
分别采用非离子表面活性剂(C_3H_6OC_2H_4O)_x(P123),阴离子表面活性剂C_(12)H_(25)NaO_4S(SDS)和C_(18)H_(29)NaO_3S(SDBS)作为模板剂,通过溶胶-凝胶再结合程序升温溶剂热一步法制备了一系列固载杂多酸光催化材料-H_6P_2W_(18)O_(62)/SiO_2。通过傅立叶-红外光谱(FTIR)、X-射线衍射(XRD)、电感耦合等离子体原子发射光谱(ICP-AES)、氮气吸附-脱附测定、透射电子显微镜(TEM)以及扫描电子显微镜配合X-射线能量色散谱仪(SEM-EDS)等测试手段对不同模板剂作用下合成产物进行了对比表征分析。结果表明,不同模板剂作用下的系列固载杂多酸-H_6P_2W_(18)O_(62)/SiO_2产物中母体多酸的Dawson基本结构均未发生明显变化,但固载后比表面积显著不同,其中,经模板剂P123和SDS作用合成的H_6P_2W_(18)O_(62)/SiO_2(P123)和H_6P_2W_(18)O_(62)/SiO_2(SDS)的比表面积高达916和634m~2·g~(-1),且显示为有序介孔材料。以二甲酚橙为模型分子,在微波场作用下,该系列固载多酸光催化性能研究结果显示,它们的光催化活性可被微波显著增强,其中,采用P123作用合成产物的光催化活性最高,60 min内对二甲酚橙的降解率达99%以上。  相似文献   

5.
采用浸渍法制备了H_3PW_6Mo_6O_(40)/ZrO_2-SiO_2催化剂,用H_2O_2进行敏化处理,并通过FT-IR、XRD对其进行了表征。探讨了该催化剂对甲基橙溶液的催化降解活性,较系统地研究了溶液的初始浓度、溶液的pH、催化剂用量对光催化降解甲基橙的影响。研究发现:H_3PW_6Mo_6O_(40)/ZrO_2-SiO_2对甲基橙有良好的降解效果。在甲基橙溶液初始浓度为10mg·L~(-1),溶液pH为2.5,催化剂用量为溶液总质量0.5%的条件下光照2.5h,甲基橙的降解率达到91.1%。H_3PW_6Mo_6O_(40)/ZrO_2-SiO_2催化剂光催化降解甲基橙溶液为一级动力学反应。  相似文献   

6.
饱和Dawson型[P_2W_(18)O_(62)]~(6-)(简称为[P_2W_(18)])多酸阴离子以其稳定的化学性质、良好的结晶性能成为多酸化学领域中的重要研究对象.本文以K_6[α-P_2W_(18)O_(62)]·xH_2O、Ce(NO_3)_3·6H_2O为基本原料,通过常规水溶液加热回流法,成功地合成了一例结构单元类似2∶17型Dawson-稀土双系列结构的一维双链化合物{[Na_2[N(CH_3)_4]_8[Ce(CH_3COO)(H_2O)]_2[Ce(H_2O)_7](P_2W_(17)O_(61))]_2·23H_2O}_n(1).结构分析表明,化合物1属于三斜晶系,P-1空间群,晶胞参数为:a=1.327 97(15)nm,b=1.376 71(15)nm,c=3.121 1(3)nm.该化合物以单缺位[P_2W_(17)O_(61)]~(10-)(简称为[P_2W_(17)])为基本构筑单元,中心原子Ce不仅与[P_2W_(17)]通过氧桥直接相连,而且通过醋酸根与另外一个Ce-[P_2W_(17)]单元相连,并最终形成新颖的一维双链结构.此外,我们还通过红外光谱、元素分析、热失重分析、紫外-可见吸收光谱分析等方法,对化合物1进行了较全面的表征.  相似文献   

7.
首次合成和离析了八种以缺位型Dawson结构钼磷杂多阴离子为配体的稀土杂多蓝K_(17)H_2[Ln-(P_2Mo_(17)O_(61))_2]·nH_2O和K_(17)H_4[Ln(P_2Mo_(17)O_(61))_2]·nH_2O(Ln=La,Pr,Sm,Yb).通过元素分析、电位滴定、红外光谱、紫外光谱、极谱、循环伏安、X射线光电子能谱、热重-差热分析和电子顺磁共振对杂多蓝进行了表征.实验结果表明,杂多阴离子还原为杂多蓝后,性质发生了某些变化,但结构基本不变,配体P_2Mo_(17)O_(61)~(10-)仍为a_2型.  相似文献   

8.
Three new polyoxometalates K_2[H_2(As_3O_3)_2(Mo_6O_(18))(NiO_6)]×H_2O(1), K_2[H_2-(As_3O_3)_2(Mo_6O_(18))(Co O6)]×H_2O(2) and [Zn(H4,4?-bpy)2(H_2O)4][(As3O3)2(Mo_6O_(18))(ZnO_6)]×4H2O(3)(4,4?-bpy = 4,4?-bipyridine) have been synthesized under hydrothermal conditions and characterized by IR, elemental analyses, XPS and single-crystal X-ray diffraction analyses, respectively. Compound 1 represents a new 3D framework structure constructed from polyoxoanion [(As3O3)2(Mo_6O_(18))(Ni O6)]4-via covalent bond. Compound 2 has an identical structure with 1. Compound 3 represents a new 2D layer structure constructed from transition metal coordination cations [Zn(H4,4?-bipy)2(H_2O)4]4+, lattice water molecules and polyoxoanions [(As_3O_3)_2-(Mo_6O_(18))(Zn O6)]4-via multi-point N–H···O and O–H···O hydrogen bonding interactions. Crystal data: for 1, cubic, space group Pa-3, a = 15.0022(8) ?, V = 3376.5(3) ?3, Z = 24; for 2, cubic space group Pa-3, a = 15.1596(10), V = 3483.88 ?3, Z = 24; for 3, monoclinic, space group C2/m, a = 19.699(4), b = 14.223(3), c = 9.1455(18) ?, β = 106.80(3)o, V = 2453.0(9) ?3, Z = 8. In addition, the magnetic behaviors for compounds 1 and 2 have been investigated.  相似文献   

9.
合成了2种过渡金属取代的多酸H_8[P_2Mo_(17)Co(OH_2)O_(61)]和H_8[P_2Mo_(17)Ni(OH_2)O_(61)],并对其抑酶活性进行了研究.结果表明,这2种化合物对酪氨酸酶均有有效的抑制效果.抑制机理表明2种化合物均是可逆竞争型抑制剂.H_8[P_2Mo_(17)Co(OH_2)O_(61)]和H_8[P_2Mo_(17)Ni(OH_2)O_(61)]的半抑制率IC_(50)值分别为(0.434 0±0.000 4)和(0.466 5±0.012 0)mmol/L,抑制常数K_Ⅰ分别为0.216 7和0.220 4mmol/L.该研究能够扩大多金属氧酸盐的应用范围.  相似文献   

10.
Dawson结构的多金属氧酸盐对酪氨酸酶的抑制作用   总被引:2,自引:2,他引:0  
按文献方法合成了两种Dawson结构的多金属氧酸盐,并对其结构进行紫外光谱和红外光谱分析。以H_6[P_2Mo_(18)O_(62)]和H_8[P_2Mo_(17)Cr(OH_2)O_(61)](简写为P_2Mo_(18)和P_2Mo_(17)Cr)为效应物,采用紫外分光光度法和酶动力学方法研究两种Dawson结构的多金属氧酸盐效应物对蘑菇酪氨酸酶二酚酶活性的抑制作用。结果表明,P_2Mo_(18)和P_2Mo_(17)Cr对酪氨酸酶二酚酶均具有显著的抑制效果,测定抑制酪氨酸酶活力下降50%的抑制浓度(IC_(50))分别为(0.482±0.009)mmol/L和(0.503±0.011)mmol/L。动力学分析表明,P_2Mo_(18)和P_2Mo_(17)Cr对酪氨酸酶的抑制作用均表现为可逆的竞争型,抑制常数K_I分别为0.212和0.249 mmol/L。其中,综合考虑IC_(50)值和抑制常数,P_2Mo_(18)对酪氨酸酶二酚酶活性的抑制效果略优于P_2Mo_(17)Cr。  相似文献   

11.
采用水热合成法,在合成金属有机骨架MOF-5的过程中引入活性组分磷钼钨杂多酸(H6P2Mo15W3O62),制备出一种新型吸附剂H6P2Mo15W3O62/MOF-5。 利用H6P2Mo15W3O62/MOF-5材料对亚甲基蓝溶液进行了材料的吸附性能研究,探讨了亚甲基蓝溶液的初始pH值和初始浓度以及不同吸附温度对吸附量的影响。 结果表明,在较低的温度和亚甲基蓝溶液较低的初始pH值的条件下,有利于H6P2Mo15W3O62/MOF-5对亚甲基蓝的吸附。 实验结果能够较好地符合Langmuir吸附等温式以及二级动力学模型,对亚甲基蓝的最大吸附量可达401.6 mg/g。 热力学参数ΔG<0、ΔH<0和ΔS>0,表明H6P2Mo15W3O62/MOF-5对亚甲基蓝的吸附过程是自发、放热的。 此外,还探讨了H6P2Mo15W3O62/MOF-5对甲基紫、孔雀石绿、罗丹明B和甲基橙等其它染料的吸附性能,结果表明,H6P2Mo15W3O62/MOF-5对阳离子染料有较好的吸附效果。  相似文献   

12.
近年来 ,无机 -有机复合材料由于其独特的结构和特殊的光、电和磁功能特性而引起科研工作者的广泛关注 [1,2 ] .杂多化合物为均一的无机多聚物 ,具有笼状结构 ,结构中均有 M3O13三金属氧簇 ,能够接受电子生成杂多蓝或杂多棕 ,加之其在水和有机溶剂中的溶解性和稳定性 ,使其在光电变色材料领域中具有潜在的应用价值 [3~ 5] .但这类化合物难于加工成实际应用的器件 ,因而限制了其进一步的应用 .利用有机组分调控的超分子自组装技术可构建光致变色同多酸或杂多酸纳米薄膜材料 ,从而为开发变色响应快、稳定性好、变色可调控的新型光电变色高密…  相似文献   

13.
Reaction of excess Fe(cp)(2) (cp = eta(5)-C(5)Me(5)) dissolved in Et(2)O with [NHex(4)](4)[S(2)Mo(18)O(62)] in acetonitrile, followed by recrystallization of the precipitated solid from N,N'-dimethylformamide (DMF), leads to isolation of the complex [Fe(cp)(2)](5)[HS(2)Mo(18)O(62)].3DMF.2Et(2)O. The solid has been characterized by microanalysis, by voltammetric analysis, by (1)H NMR, diffuse reflectance infrared, EPR, and M?ssbauer spectroscopies, and by temperature-dependent magnetic susceptibility measurements. The data are consistent with the presence of a paramagnetic [Fe(cp)(2)](+) cation and a diamagnetic two-electron-reduced [HS(2)Mo(18)O(62)](5-) anion. The related salt [NBu(4)](5)[HS(2)Mo(18)O(62)].2H(2)O crystallizes in space group C2/c with a = 25.1255(3) A, b = 15.4110(2) A, c = 35.8646(4) A, beta = 105.9381(4), V = 13353.3(3) A(3), and Z = 4. The (2 e(-), 1 H(+))-reduced anion exists as the alpha-Dawson isomer, and its structure may be compared with those of the oxidized and (4 e(-), 3 H(+))-reduced anions as they exist in [NEt(4)](4)[S(2)Mo(18)O(62)].MeCN and [NBu(4)](5)[H(3)S(2)Mo(18)O(62)].4MeCN, respectively. Overall, the anion expands significantly upon the addition of two and then four electrons. However, the Mo...Mo distances along the bonds which connect the two equatorial belts decrease in the order 3.801, 3.780, and 3.736 A, making these distances the shortest for the three inequivalent sets of corner-sharing octahedra in each anion. This is consistent with the two or four added electrons localizing essentially in molecular orbitals which are bondiing with respect to interactions between the belts.  相似文献   

14.
Sun C  Li Y  Wang E  Xiao D  An H  Xu L 《Inorganic chemistry》2007,46(5):1563-1574
By synthesizing the novel molybdenum arsenate complexes, we have obtained eight new structures, namely, (4,4'-bipy)[Zn(4,4'-bipy)2(H2O)2]2[(ZnO6)(AsIII3O3)2Mo6O18].7H2O, 1, [Zn(phen)2(H2O)]2[(ZnO6)(AsIII3O3)2Mo6O18].4H2O, 2, [Zn(2,2'-bipy)2(H2O)]2[(ZnO6)(AsIII3O3)2Mo6O18].4H2O, 3, [Zn(H4,4'-bipy)2(H2O)4][(ZnO6)(AsIII3O3)2Mo6O18].8H2O, 4, (H24,4'-bipy)[CuI(4,4'-bipy)]2[H2AsV2Mo6O26].H2O, 5, (H24,4'-bipy)3[AsV2Mo6O26].4H2O, 6, (H24,4'-bipy)3[AsV2Mo6O26(H2O)].4H2O, 7, and (H24,4'-bipy)2.5(H3O)[AsV2Mo6O26(H2O)].1.25H2O, 8 (4,4'-bipy = 4,4'-bipyridine, 2,2'-bipy = 2,2'-bipyridine, phen = 1,10-phenanthroline). These structures were determined by single-crystal X-ray diffraction analysis and were further characterized by elemental analysis, IR, XPS spectroscopy, and TG analysis. The structure of 1 is constructed from two-dimensional square gridlike sheets linked by the polyanions [(ZnO6)(AsIII3O3)2Mo6O18]4- via hydrogen-bonding interactions to form a three-dimensional supramolecular framework with two types of channels. Compounds 2 and 3 display similar bisupported structures. Compound 4 features a three-dimensional supramolecular architecture. Compound 5 possesses a 1D infinite ladderlike ribbon. Compounds 6-8 are discrete structures exhibiting three isomeric forms of [HxAs2Mo6O26](6-x)-. Furthermore, compound 8 represents a new isomer B'-[As2Mo6O26(H2O)]6-. In addition, the fluorescent properties of compounds 1-3 are reported.  相似文献   

15.
Reaction of the microporous metal-organic framework Zn4O(BDC)3 (BDC2- = 1,4-benzenedicarboxylate) with Cr(CO)6 at 140 degrees C in a 6:1 mixture of dibutylether and THF affords Zn4O[(BDC)Cr(CO)3]3 (1). This compound retains the porous cubic structure of the parent framework, but features Cr(CO)3 groups attached in an eta6 fashion to all of the benzene rings. Compound 1 is also microporous, exhibiting a BET surface area of 2130 m2/g. It can be fully decarbonylated by heating at 200 degrees C, but the resulting gray solid (2) shows little affinity for N2 or H2 at 298 K, suggesting aggregation of the chromium atoms. In contrast, photolysis of 1 using 450-nm light in an atmosphere of N2 or H2 produces solids with infrared spectra indicative of Zn4O[(BDC)Cr(CO)2(N2)]3 (3) and Zn4O[(BDC)Cr(CO)2(H2)]3 (4). Under an N2 atmosphere, compound 4 completely converts into compound 3 over the course of 12 h, demonstrating the lability of the Cr0-H2 bond. Owing to isolation of the metal centers within the rigid, evacuable framework structures, the N2- and H2-substituted compounds show greatly enhanced stability relative to molecular analogues generated in frozen gas matrices or supercritical fluid solutions.  相似文献   

16.
采用非离子表面活性剂C18H37(OCH2CH2)10OH(Brij-76)作为模板剂, 在以杂多酸H6P2W18O62对TiO2掺杂改性基础上, 通过模板-溶胶-凝胶-程序升温溶剂热一步法在较低温度下制备了有序复合介孔材料H6P2W18O62/TiO2(Brij-76). 通过傅立叶变换红外(FT-IR)光谱, X射线衍射(XRD), 扫描电子显微镜(SEM), 能量色散X射线(EDX), N2吸附-脱附测定和NH3程序升温脱附(NH3-TPD)等手段对其进行了表征. 结果表明, 以非离子表面活性剂Brij-76为模板剂制得的复合材料H6P2W18O62/TiO2(Brij-76)平均孔径约为3.31 nm, BET比表面积为99.78 m2·g-1. 与TiO2相比, 其孔径有序性大幅度提高, 粒子的聚集度降低, 表面酸性显著增加. 微波增强光催化性能研究结果显示, H6P2W18O62/TiO2(Brij-76)在微波作用下催化活性更高, 可有效地降解一氯苯溶液.  相似文献   

17.
[C6N2H18]2[Mo5O15(HPO4)2]·H2O的水热合成与结构表征   总被引:6,自引:0,他引:6  
通过水热法合成了一个新化合物[C6N2H18]2[Mo5O15(HPO4)2]·H2O,并通过IR光谱、ICP、元素分析、差热与热重分析和X射线单晶衍射分析等手段进行了表征.结果表明,晶体属三方晶系,P3(2)21空间群,a=1.1231(1)nm,c=2.2802(5)nm,V=2.4911(7)nm3,Dx=2.835Mg/m3,Z=6,最后的一致性因子R=0.0227,wR=0.0675.阴离子中Mo5O15构成一环状结构,2个HPO4一个连在环的下方,一个连在环的上方,形成类似于“飞碟”状的结构,阳离子为2个质子化的四甲基乙二胺.  相似文献   

18.
刘杰 《结构化学》1998,17(3):225-229
采用电解法制备了未见文献报道的杂多蓝H8[SiMo11Co(H2O)O39]·20H2O,通过X-射线衍射测定了其晶体结构,该晶体属单斜晶系,空间群P21;。晶胞参数全矩阵最小二乘法修正至中心原子Si与4个氧形成四面体结构,配原子M(M=11/12Mo+1/12Co)与O形成12个MO6八面体结构3个MO6共边形成4个M3O13三金属簇,4个三金属簇与SiO4四面体共角相连形成阴离子结构。  相似文献   

19.
<正> Crystal of the title complex [(n-C4H9)4N]3[Mo6O18(N2C6H3-2,4-(NO2)2](Mr= 1710. 5) is orthorhombic with space group P21cn (Pna21), a = 17. 304(3), b = 17.580(2), c=24. 355(4) (?), V = 7409(2)(?)3, Z = 4, Dc=1. 60g/ cm3, μ=10. 29cm-1, F (000) = 3647. The structural solutions and refinements based on 3900 reflections (I≥3σ(I)) converged at R = 0. 0575, Rw =0. 0498. The atoms of Mo(3), Mo(4), O(1), O(5), O(9), O(11) and the [N2C6H3-2,4-(NO2)2] unit in the complex anion locate approximately in a plane about which the complex anion is nearly symmetrical.  相似文献   

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