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1.
类水滑石及其杂多阴离子柱撑物的合成与表面酸性研究   总被引:1,自引:0,他引:1  
合成了一些类水滑石和过渡金属取代型杂多酸盐,并由此制备了相应杂多阴离子柱撑水滑石层柱材料。用XRD,IR和元素分析等手段对合成产物进行组成和结构表征,用NH3-TPD,Py-IR研究了合成产物的表面酸性和酸类型,并在异丙醇反应中考察了合成物的酸碱催化行为,结果表明,水滑石和柱撑水滑石均同时存在酸碱中心,且酸碱相对强度与柱阴离子类型密切相关。杂多阴离子进入水滑石层,同时改变了水滑石和杂多酸盐的酸强度  相似文献   

2.
杂多阴离子柱撑锰铝水滑石的合成、表征及催化性能   总被引:4,自引:0,他引:4  
刘继广  孙铁  蒋大振 《催化学报》1995,16(3):41-244
杂多阴离子柱撑锰铝水滑石的合成、表征及催化性能刘继广,孙铁,蒋大振(吉林大学化学系,长春130023)关键词杂多阴离子,柱撑,锰铝水滑石,异丁烷,烷基化类水滑石化合物属于阴离子型粘土‘’‘,其中心金属离子M2+或M3+及平衡阴离子可根据需要进行改变....  相似文献   

3.
采用离子交换法将过渡金属离了三元取代钨杂多阴离子引入Zn2Al型阴离子粘土层内,得到柱撑水滑石Zn2Al(OH)6-SiW9Z3O40(Z=Ti^4+,Mo^6+)及Zn2Al(OH)6-SiW9Fe3(H2O2)3O37。ZRD及IR表明,杂多阴离子引入水滑石层间后,水滑石层内高度为1.0nm。  相似文献   

4.
柱撑化合物Zn2Al-PW11Z的结构模型及酯化活性   总被引:1,自引:1,他引:1  
杂多化合物是性能优异的酸型和氧化型或双功能催化剂[1-4],而通式为的阴离子粘土通常具有减催化或还原催化性能[5,6].因此,从在分子及原子水平上设计催化剂,调控催化性能观点出发,人们期望将体积较大的杂多阴离子嵌入阴离子粘土层间,合成大层间距的新型柱撑微孔材料.1988年Pinnavaia等人[7]首次报导了Zn2Al-V10O28是具有2.0nm孔径分布的中微孔材料.最近,笔者将单取代型Keggin结构杂多阴离子GeW11O39Z(H2O)6-(其中Z=Ni2 和Cu2 )和缺位Keggin结构的GeW11O嵌入Zn2Al-NO3层间,合成了通道高度为0.9nm的新型柱撑…  相似文献   

5.
通过离子交换法, 将含钛过渡金属离子一、三取代钨硅、钨磷过氧杂多配合物嵌入Zn2Al类水滑石中, 获得了柱撑化合物, 并用XRD, IR, XPS, 元素分析等手段对产物的结构和组成进行了表征。结果表明, 过氧杂多阴离子进入水滑石层间后, 水滑石的层间距从0.92nm增大到1.47nm, 且O2^2^-链没有被破坏。柱撑产物在环己烯氧化反应中显示优良的催化性能。  相似文献   

6.
ZnCuCoAlNO3型四元水滑石及其多氧阴离子柱撑物的合成与催化氧化性能郭军*黄兰芳**矫庆泽张斌蒋大振(吉林大学化学系,长春130023)闵恩泽(石油化工科学研究院,北京100083)关键词:ZnCuCoAlNO3四元水滑石杂多阴离子柱撑物合成催...  相似文献   

7.
从NO_3-LDH出发,通过直接交换反应合成了具有Keggin结构的杂多阴离子SiW_(11)M·(H_2O)O (M为第一系列过渡金属)柱撑水滑石,用元素分析、XRD、IR和DTA对产物的组成和结构进行了表征。结果表明,杂多阴离子进入水滑石层间,使水滑石的层间距从0.92nm增加到1.47nm,且热稳定性有所提高。柱撑产物在异丙醇反应中表现出酸碱双功能催化作用,但酸催化占明显优势。  相似文献   

8.
P-Cu-Mo杂多阴离子柱撑水滑石的制备   总被引:1,自引:0,他引:1  
杂多阴离子柱撑水滑石作为一类新型的催化材料,近年来日益受到人们的关注。但由于杂多化合物对碱不稳定及水滑石在酸性条件下层结构易被破环,故文献中仅有制得钨硅系杂多阴离子柱水滑石的报道。作者将过渡金属引入钼磷酸的Keggin结构骨架中,提高了其溶液稳定性,并在微波场中快速地制得了P-Cu-Mo杂多阴离子柱撑水滑石。  相似文献   

9.
柱撑水滑石类层柱状阴离子粘土是一类新型层柱材料,由于其二维孔道结构的可调变性及潜在的择形催化性能,已引起人们的重视[1-3].迄今,人们已合成了包括无机和有机阴离子,同多和杂多阴离子(Polyoxometalates,简称POMs)以及配合物阴离子在内的多种柱撑水滑石,其中同多和  相似文献   

10.
杂多阴离子柱撑水滑石类层柱材料中层柱相互作用研究   总被引:14,自引:0,他引:14  
合成了具有不同组成的类水滑石层状化合物和杂多酸,据此制备了一系列杂多阴离子柱撑水滑石,用IR光谱、DTA等方法研究了此类层柱材料中层与柱的相互作用,发现类水滑石层状化合物中的M^3+离子的种类和具有Keggin结构的杂多阴离子的组成元素,无论处于四面体中、还是位于八面体中,对层柱的相互作用皆有明显影响,此外,这种相互作用还导致杂多阴离子中四面体和八面体对称性及相关性质的改变。  相似文献   

11.
Some new Schiff bases were synthesized by the condensation ofequimolar quantities of salicylaldehyde and 2-amino-5-phenylazo-pyridine orits derivatives in dry benzene(1):Metal complexes of the type ML_2and M'L_3where M=Cu~(2+),Co~(2+),Ni~(2+),Mn~(2+)Pd~(2+),M'=Fe~(3+)and L=different newly synthesizedmonobasic Schiff bases were prepared in absolute ethanolic medium(2)andcharacterized by elementary analysis,conductance measurements,infraredspectra,electronic spectra,magnetic moments studies.  相似文献   

12.
采用密度泛函理论B3LYP方法计算了吡啶取代的Lindqvist型多酸(POMs)的线性(最大吸收波长, λmax)和非线性光学(NLO)[超瑞利散射(HRS)的第一超极化率, βHRS]性质, 探讨了其作为潜在阳离子检测剂的可能性. 金属离子吸附能计算结果表明, 吡啶取代的Lindqvist型多酸配体与金属离子之间均有较强的相互作用, 相互作用强度大小顺序为Ni2+>Cu2+>Co2+>Fe2+>Zn2+>Mg2+>Ca2+. 电子光谱和βHRS计算结果表明, 引入适当的供、 受电子基团对该多酸配体进行修饰可有效调节线性和二阶NLO性质; 同时, 吡啶取代的Lindqvist型多酸对7种金属离子(Cu2+, Zn2+, Ca2+, Mg2+, Ni2+, Co2+, Fe2+)表现出了不同的检测行为.  相似文献   

13.
研究了Keggin结构钼磷杂多化合物Na5[PM(H2O)Mo11O39]·nH2O(M=Mn2+,Co2+,Ni2+,Cu2+,Zn2+在溶液中的氧化还原性质,发现环境的改变可对杂多阴离子的极谱半波电位产生影响,其影响程度的大小决定于过渡金属离子本身的性质。取代后的钼磷杂多阴离子的半波电位顺序为Ni2+>Co2+>Zn2+>Cu2+>Mn2+,pH值的变化影响氧化还原性质,并阐述了变价金属Cu2+对杂多阴离子氧化还原性质的影响.  相似文献   

14.
Zn2Al layered double hydroxide pillared with Dawson polyoxometalates, P2W17ZO618-(Z=Mn2+, Co 2+, Ni2+, Cu2+, Zn2+) was prepared. A basal space of ca. 16 nm indicates the intercalated Dawson ions to be oriented with their C2 axis perpendicular to the double hydroxide layers(with the exception of P2W17Zn-LDH). The IR and13P MASNMR spectral reveal that the Dawson ions retain their integrity in the interlayer space of LDH. A preliminary study shows that these compounds are highly active catalysts for the oxidation of cyclohexene with molecular oxygen.  相似文献   

15.
We reported four fluorescent chemosensors containing tryptophan units. The fluorescence spectrum titration experiments suggest that chemosensors 1, 2, 3 and 4 are highly selective for Cu2+ and Fe3+ over Li+, Na+, K+, Co2+, Zn2+, Ni2+, Hg2+ and Cr3+ via forming complexes with Cu2+ or Fe3+, which is confirmed by dramatical quench of fluoreseence in aqueous solution at pH 7.4, thus making all the chemosensors suitable for Cu2+ and Fe3+ fluorescent sensors.  相似文献   

16.
Alkyl-substituted pyridine-2-carboxylic acids have been found to be efficient reagents for the extraction of Cu2+, Fe3+, Co2+ and Ni2+ from aqueous sulfate solutions at pH 1.7. The effects of the position and the nature of the substituent are discussed.  相似文献   

17.
Transition metal complexes with a tetragonal planar structure of a dithiolene and a diimine have excellent electronic functions due to the intramolecular charge transfer from a ligand to other ligand (LL'CT)[1-3]. Our interest is in the metal complexes of the dicyno-dithiolene and some diimine such as substituted and unsubstituted phenanthrolines and bipyridines. In the present work we studied synthesis, characterization, photo-physical and photochemical properties of the title complexes M(mnt)(dmbpy),M=Mn,Fe,Co, Ni, Cu,Zn.  相似文献   

18.
以蒽,醋酸,溴化氢,1,3,5-三聚甲醛,N,N,N-三甲基-1-十四烷基溴化铵,双(2-吡啶基甲基)胺,三乙胺等为原料,合成了含蒽的双三联吡啶化合物,其结构经1H NMR、 13C NMR和HR-MS表征。目标产物中含有双三联吡啶结构,可以与金属离子之间具有较强的螯合作用,从而改变原来目标化合物的光学性质,尤其是其荧光性能。实验结果表明:体系中随着Zn2+、Ag+和Mn2+浓度不断增大,含蒽双三联化合物荧光强度不断增强;Cu2+、Co2+、Hg2+、Pb2+、Na+、Fe3+、Ni2+均随着浓度的增大,含蒽双三联化合物荧光强度不断减弱。在此基础上,运用荧光光谱法能高灵敏度的检测痕量金属离子。   相似文献   

19.
A novel coumarin derivative[7-diethylamino-2-oxo-2H-chromene-3-carboxylic acid(6-amino-pyridin2-yl)-amide,CFe1] has been synthesized and its potential application as a chemosensor for the detection of metal ions has been further investigated.The responses of CFe1 to Fe^3+ were studied by fluorescence emission spectrometry in the presence of other metal ions such as Al^3+,Ba^2+,Ca^2+,Co^3+,Cr^3+,Cu^2+,Fe^2+,Hg^2+,Mg^2+,Mn^2+,Na^+,Ni^+,Pb^2+,Zn^2+,K^+,and Ag^+.CFe1 showed a good selectivity for Fe^3+ with fast response,a wide pH span of 3.3-9.18,and a large Stocks shift.CFe1 in the presence of Fe^3+ and ethylene diamine tetraacetic acid(EDTA) makes the blue solution fade to colorless,which is due to the formation of CFe1-Fe^3+ complex instead of any catalytic action of Fe^3+.Furthermore,the imaging of Fe^3+ in cultured single mice microglia cells was realized with the aid of CFe1,indicating that CFe1 has a great potential to be used as promising models for the future design of novel and robust chemosensor for metal ion detection in the field of biomedical and environmental analyses.  相似文献   

20.
Simple structural compounds 1 to 3 were synthesized.The presence of Cu2+ resulted in the fluorescence and absorption spectra change of 1 and 2,which indicated that 1 and 2 showed a highly selective response to Cu2+ over other metal ions.However,3 showed no selectivity for metal ions,which means that the compound could bind with several metal ions,such as,Ni2+,Zn2+,Cd2+.Hg2+, Pb2+,Fe3+,Mg2+,Ca2+,and Co2+,except Cu2+ and Ag+.The different spectral responses were attributed to the difference in binding sites for 1 and 3.  相似文献   

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