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1.
在可见光照射下, 负载有2,2´-联吡啶铁(II)络合物的Laponite粘土能够有效地活化分子氧降解染料罗丹明B, 在水溶液中的2,2´-联吡啶铁(II)络合物则没有任何光催化活性. 该催化剂能够循环降解罗丹明B并且保持很好的光催化活性, 粘土催化剂易于通过离心或者沉降从体系中分离. 测定了光催化剂降解罗丹明B的TOC去除率和体系中的活性氧物种, 并且对催化反应机理进行了讨论.  相似文献   

2.
本文利用所合成的4'-(4''-重氮基)苯基-(2,2':6',2')-三联吡啶氟硼酸盐(Diazo-tpy)在紫外光照射下的光分解反应特性,实现三联吡啶基团与基片之间形成共轭价键连接,这不仅提高了自组装膜的稳定性,而且降低了载流子在两者之间传输时的阻抗;在此基础上,通过两端含三联吡啶的直线型配体1,4-二-(2,2':6',2'-三联吡啶)基苯(Bi-tpy)与四种过渡金属离子(Mtn+:Pt4+、Ru3+、Rh3+、Pd2+)之间的配位作用,通过层-层自组装制备了全共轭金属-有机自组装超薄功能膜。由紫外-可见光谱跟踪自组装过程证明了自组装过程的成功实现,还分析了金属离子的种类对自组装的影响规律。光电转换测试表明Bi-tpy/Ru3+自组装膜要比Bi-tpy/ Pt4+具有更明显的光电转换性能;同时,由于缺陷与阻抗随层数的增加而增大的原因,在自组装6层时光电流达到最大值。这为我们设计新型光电转换器件提供参考依据。  相似文献   

3.
通过控制固/液界面电极电位的方式, 控制表面活性剂和金属离子在电极表面的自组装, 制备出了高度取向的ZnO/表面活性剂复合多层膜. 对无机层形态和结构进行了分析, 并采用X射线反射率和X射线漫散射研究了电极电位控制下ZnO/表面活性剂复合多层膜在固/液界面的自组装生长. 结果表明, 在一定电位下, 只有当表面活性剂浓度低于其饱和吸附浓度时, 采用阶跃电位沉积方式才能明显改变复合薄膜的周期厚度; 恒电位沉积方式控制电极电位时, 随着沉积电位的提高, 多层膜层状结构由一组层状相变为多组层状相, 同时层状结构的取向变差. 实验研究结果验证了电化学自组装过程是由金属离子的还原速度和表面活性剂的吸附速度二者共同控制完成的.  相似文献   

4.
联吡啶铁/H2O2体系在可见光下降解芥子气模拟剂2-CEES   总被引:2,自引:0,他引:2  
采用联吡啶铁/H2O2体系在可见光照射条件下(λ>450nm)降解芥子气模拟剂2-氯乙基乙基硫醚(2-CEES).考察了不同反应条件下的降解效果,通过EPR分析确定了反应过程中产生的高活性物种,利用GC-MS和NMR等方法分析了反应的产物,跟踪了反应过程中TOC的变化,并根据结果对2-CEES光催化降解的反应机理进行了探讨.  相似文献   

5.
以4,4'-二硝基-2,2'-联吡啶-6,6'-二亚甲基双三氟乙酸酯作为起始原料, 经水解、 溴化、 酯化和对氨基苯乙炔取代4步反应合成了4,4'-二(对氨基苯乙炔基)-6,6'-二[N,N-二(乙氧基羰甲基)氨甲基]-2,2'-联吡啶. 通过红外光谱、 核磁共振波谱、 高分辨质谱等表征了该化合物的结构. 该化合物经水解后与铕离子形成稀土荧光螯合物, 在紫外光激发下, 发射出具有铕离子特征的荧光光谱.  相似文献   

6.
以4,4'-二硝基-2,2'-联吡啶-6,6'-二亚甲基双三氟乙酸酯作为起始原料,经水解、溴化、酯化和对氨基苯乙炔取代4步反应合成了4,4'-二.(对氨基苯乙炔基)-6,6'-二[N,N-二(乙氧基羰甲基)氨甲基]-2,2'-联吡啶.通过红外光谱、核磁共振波谱、高分辨质谱等表征了该化合物的结构.该化合物经水解后与铕离子形成稀土荧光螯合物,在紫外光激发下,发射出具有铕离子特征的荧光光谱.  相似文献   

7.
以玻碳电极为基础电极,先用静电自组装方法将带负电荷的四磺酸基苯基铁卟啉和带正电荷的含重氮盐基团的重氮树脂在电极表面进行层-层组装,然后在紫外光的照射下,使铁卟啉的磺酸基与重氮树脂的重氮基引发交联反应,使层与层之间的离子键变成共价键,从而使铁卟啉在电极表面形成稳定、有序、分子水平的层-层构筑.用UV-Vis和IR光谱表征了组装过程,用CV方法研究了该电极的电化学性能.结果表明,该电极不但具有非常优异的稳定性,而且对H2O2的电还原反应也表现出很好的催化活性.  相似文献   

8.
共价键合四磺酸基铁酞菁有序多层膜电极   总被引:2,自引:1,他引:1  
以玻碳电极为基础电极,经静电自组装方法将带负电荷的四磺酸基铁酞菁与带正电荷的含重氮基团的重氮树脂在电极表面进行层-层自组装,然后经紫外光照射,使铁酞菁的磺酸基与重氮树脂的重氮基发生交联反应,使层与层之间的离子键转为共价键,从而使铁酞菁在电极表面形成稳定、有序且处于分子水平的层-层构筑.用UV-Vis和IR光谱表征了组装过程,用CV方法研究了该电极的电化学性能及其对三氯乙酸的电催化还原.同时用计时电流法测定了三氯乙酸通过该类膜的扩散系数.  相似文献   

9.
采用室温固相研磨的方法,4,4'-联吡啶与连有阻塞基的乙氧乙醇磺酸酯(或苄溴)反应,得到单取代的4,4'-联吡啶六氟磷酸盐(2),2再与α,α'-二(溴甲基)-2,2'-联吡啶反应,得到哑铃型化合物--2,2'-联吡啶桥连的双-4,4'-联吡啶六氟磷酸盐(3),收率约90%.2和3的结构经1H NMR, 13C NMR和MS表征.  相似文献   

10.
报道了由芳香醛合成4,4',6,6'-取代-2,2'-联吡啶化合物的方法,合成了一系列钠穴状化合物以及两个铕穴状化合物[Eu?bpy·bpy·bpy]·2Cl·Br(bpy=6,6'-二亚甲基-2,2'-联吡啶-4,4'-二甲酯)(23)和[Eu?bpy~1·bpy~1·bpy~2]·2Cl·Br(bpy~1=6,6'-二亚甲基-2,2'-联吡啶-4,4'-二甲酸,bpy~2=6,6'-二亚甲基-2,2'-联吡啶-4,4'-二甲酰乙二胺)(24).目标化合物均经过~1H NMR、13C NMR和高分辨质谱(HRMS)表征.X射线单晶衍射(XRD)和HRMS鉴定了铕穴状化合物23的结构.对23的荧光光谱(PL)、荧光衰减曲线和绝对量子产率(η)的研究结果表明,23能够有效地被近紫外光激发,显示荧光寿命(τ)为0.32 ms,η为70%的亮红色荧光,表明23是一种在发光和照明显示之中有着潜在应用的荧光材料.  相似文献   

11.
系统地研究了Ce(IV), H2SO4, Ru(bipy)3^2^+和5种α-羟基羧酸对Ce(IV)氧化钌(II)-联吡啶化学发光反应速率的影响。结果表明,在选定的试验条件下, 化学发光反应速率分别与Ce(IV),Ru(bipy)3^2^+, 5种α-羟基羧酸的浓度和1/[H2SO4]^2成正比, 据此提出了偶合化学发光反应机理, 推导得到的反应速率方程与实验结果吻合。  相似文献   

12.
Two new intercalation compounds Fe0.90PS3(phen)0.41 (1) (phen stands for 1,10-phenanthroline including a part of 1, 10-phenanthroline H ) and Fe0.83PS3(bipy)0.34 (2) (bipy stands for 2,2'-bipyridine H ) were synthesized by the reaction of the layered FePS, with 1,10-phenanthroline or 2,2'-bipyridine in the presence of anilinium chloride. They were characterized by elemental analyses, powder X-ray diffraction (XRD), infrared spectroscopy. The lattice spacing of the intercalate was expanded by 0.90 nm for Fe0.90PS3(phen)0.41 and 0.57 nm for Fe0.83PS3(bipy)0.34 withrespect to the pristine FePS3, indicating that the ring plane of the guests is perpendicular to the layer of the host. The UV-vis absorption spectra of the filtrate in preparation of the intercalates indicate that 1, 10-phenanthroline or 2,2'-bipyridine also acts as a complexing agent to remove intralamellar Fe2 ions into the solution during intercalation. The magnetic properties of 1 and 2 were studied.  相似文献   

13.
Excitation of solutions of Fe(bipy)2(CN)2 by a 266-nm laser pulse produces a hydrated electron and the oxidized complex, Fe(bipy)2 (CN)2+, in the primary photochemical step, in homogeneous aqueous solution as well as in aqueous solutions containing cetyltrimethylammonium bromide (CTAB) or sodium dodecyl sulfate (SDS) micelles. In all cases nascent hydrated electrons react with ground state Fe(bipy)2(CN)2 to form Fe(bipy)2(CN)2, and comparison of the decay constants in the three media (H2O: k = 2.8 × 1010 M−1 s−1; CTAB: k = 2.9 × 1010 M−1 s−1; SDS: k = 5.5 × 109 M−1 s−1), shows that the reaction is essentially unaffected by CTAB micelles but is much slower in SDS solution. Similar micellar effects were found for the back reaction between eaq and Fe(bpy)2(CN)2+. Rate constants for the scavenging of the photogenerated hydrated electrons by methyl viologen (MV2+) cations and NO3 anions were measured in the three systems, and the results indicate that for scavenging by MV2+ the rate constants are decreased in the micelle systems (k in H2O, 8.4 × 1010; CTAB, 3.5 × 1010 and SDS, 1.58 × 1010 M−1 s−1), whereas for NO3 the CTAB micelle decreases while the SDS micelle enhances the scavenging compared to water solution (k in H2O, 8.3 × 109; CTAB, 7 × 108; and SDS, 2.05 × 1010 M−1 s−1). For the comproportionation reaction between Fe(bipy)2(CN)2+ and Fe(bipy)2(CN)2 both micelles reduce the rate (k in H2O, 3.3 × 1010; CTAB, 2.3 × 1010; and SDS, 1.05 × 1010 M−1s−1), but while the reaction of Fe(bipy)2(CN)2+ with MV+ is increased in CTAB compared to water, it is slowed in SDS (k in H2O, 2.4 × 1010; CTAB, 8.9 × 1010; and SDS, 1.8 × 1010 M−1s−1). All effects observed in these microheterogeneous systems can be uniformly interpreted in terms of Coulombic interactions between the actual reactants and the charged surface of the micelles.  相似文献   

14.
羧甲基壳聚糖对亚铁离子的吸附   总被引:12,自引:0,他引:12  
壳聚糖是由甲壳素经脱乙酰基后得到的一种天然高分子氨基多糖 ,它是金属离子的良好配体 ,其配合物在工业、农业、食品、环保、医药等方面的应用已有许多研究 [1~ 4 ] .脱乙酰基后的壳聚糖溶解性有很大改善 ,但仍只能溶于酸或酸性水溶液 ,限制了它的推广应用 .通过化学改性的羧甲基壳聚糖 ( CMCS)具有良好的水溶性、保湿性、乳化性 ,其分子中含有— OH、— NH2 、—COOH等基团 ,能有效络合金属离子 [5] .人体对壳聚糖 -亚铁络合物的吸收远远大于传统的 Fe SO4 药物 [6 ] ,壳聚糖及其衍生物与 Fe2 的络合物有可能用于治疗缺铁性贫血 …  相似文献   

15.
The formal standard rate constants for the redox systems, Fe(bipy)33+/Fe(bipy)32+,Fe(bipy)2(CN)2?/Fe(bipy)2(CN)2, Fe(bipy)(CN)4?/Fe(bipy)(CN)42? and Fe(CN)63?/Fe(CN)64? (bipy=2,2′-bipyridine), in aqueous solution and N,N-dimethylformamide solution are measured with the aid of the galvanostatic double pulse method. The standard rate constant decreases as the number of the coordinated 2,2′-bipyridine decreases. It is in accordance with the trend in the homogeneous rate constants for these systems and is interpreted on the basis of the extension of ligand π-orbitals. This finding may be evidence for the mechanistic similarity of the electrochemical electron-transfer reaction of a redox system to the corresponding homonuclear electron-exchange reaction occurring in solution phase. An empirical relation between rate constants for both kinds of reactions is discussed. It is noted that the maximum electrochemical rate constant is limited at a value much smaller than the one theoretically allowed.  相似文献   

16.
Summary Charge-transfer transitions of Ru(bipy) 3 2+ , Fe(bipy) 3 2+ , Fe(CN) 6 3- , and free bipy (bipy=2,2-bipyridine) are solvent dependent. Evidence is presented that dielectric continuum theory provides a reasonable basis for interpreting medium effects on the electronic transition energies in binary solvent mixtures as well as in pure solvents.  相似文献   

17.
1 INTRODUCTION Recently, functional models for oxo-bridged diiron (Ⅲ) complexes have received much attention[1, 2]. They provide structural models for diiron sites in several proteins involved in oxygen storage of hemerythrin[3] and oxygen activation of methane monooxygenase[4]. In addition, several synthetic FeOFe (-oxo) diiron(Ⅲ) complexes show catalase-like activity[5, 6]. One of our studies in this respect is trying to synthesis -oxo bridged diiron complexes. The compound [Fe(ph…  相似文献   

18.
Dinuclear and trinuclear ferrocene complexes {[Fc2BMe2]Li, [Fc-BMe2-fc-BMe2-Fc]Li2, Fc2B(pyind), [Fc2B(bipy)]PF6, [Fc-B(bipy)-fc-B(bipy)-Fc](PF6)2} bearing anionic, uncharged, and cationic four-coordinate boron bridges have been synthesized (Fc: ferrocenyl; fc: 1,1'-ferrocenylene; pyind: 5-fluoro-2-(2'-pyridyl)indolyl; bipy: 2,2'-bipyridyl). The molecular structures of [Fc2BMe2]Li(12-crown-4)2, [Fc-BMe2-fc-BMe2-Fc](Li(12-crown-4)2)2, Fc2B(pyind), and [Fc2B(bipy)]PF6 were determined by X-ray crystallography. The anionic aggregates [Fc2BMe2]- and [Fc-BMe2-fc-BMe2-Fc]2- are very sensitive to air and moisture whereas bromide salts of their cationic counterparts [Fc(2)B(bipy)]+ and [Fc-B(bipy)-fc-B(bipy)-Fc]2+ may be dissolved in water without decomposition. Cyclic voltammograms of the diferrocene species show two well-resolved one-electron transitions separated by 0.21 V ([Fc2BMe2]Li; Eo' = -0.43 V, -0.64 V; vs. FcH/FcH+), 0.18 V (Fc2B(pyind); Eo' = -0.03 V, -0.21 V), and 0.16 V ([Fc2B(bipy)]PF6; Eo' = +0.23 V, +0.07 V), which indicates electronic interactions between the two ferrocenyl substituents. Two redox waves with an intensity ratio of 1:2 are observed in the cyclic voltammograms of the trinuclear derivatives [Fc-BMe2-fc-BMe2-Fc]Li2 and [Fc-B(bipy)-fc-B(bipy)-Fc](PF6)2. In the case of the BMe(2)-bridged species, the electrochemically unique central ferrocenylene unit is oxidized at a much more cathodic potential value (Eo' = -1.21 V) than the two terminal ferrocenyl substituents (Eo' = -0.51 V). The opposite is true in the case of the B(bipy)-bridged trimer where oxidation of the terminal ferrocenyl groups (Eo' = +0.03 V) precedes oxidation of the internal iron atom (Eo' = +0.26 V). The Fe(II)/Fe(III) redox potentials of the mono- and dianionic species differ to a much larger extent from the redox potential of parent ferrocene (Eo' = 0 V) than the Eo' values of the corresponding mono- and dicationic derivatives. Apart from electrostatic interactions, the electrochemical properties of BMe2- and B(bipy)-bridged oligoferrocenes are determined by the pronounced positive inductive effect of triorganoborate substituents together with positive sigma/pi* hyperconjugation on the one hand and ferrocene-to-B(bipy) charge transfer on the other.  相似文献   

19.
Three simple, sensitive, and reproducible spectrophotometric methods (A-C) for the determination of pipazethate hydrochloride (PiCl) in pure form and in pharmaceutical formulations are described. The first and second methods, A and B, are based on the oxidation of the drug by Fe3+ in the presence of o-phenanthroline (o-phen) or bipyridyl (bipy). The formation of tris-complex upon reactions with Fe3+-o-phen and/or Fe3+-bipy mixture in an acetate buffer solution of the optimum pH values was demonstrated at 510 and 522 nm, respectively, with o-phen and bipy. The third method, C, is based on the reduction of Fe(III) by PiCl in acid medium and subsequent interaction of Fe(II) with ferricyanide to form Prussian blue, which exhibits an absorption maximum at 750 nm. The concentration ranges are from 0.5 to 8, 2 to 16, and 3 to 15 microg/mL for Methods A-C, respectively. For more accurate analysis, Ringbom optimum concentration ranges were calculated. The molar absorptivity, Sandell sensitivity, and detection and quantitation limits were calculated. The developed methods were successfully applied to the determination of PiCl in bulk and pharmaceutical formulations without any interference from common excipients. The relative standard deviations were < or =0.83% with recoveries of 98.9-101.15%.  相似文献   

20.
The bipyridine (bipy) and its cobalt complex (Co-bipy) were tested as corrosion inhibitors for N80 carbon steel in 0.1 M H2SO4 solution by electrochemical polarization and electrochemical impedance spectroscopy (EIS) method. Scanning electron microscopy (SEM) techniques were used to characterize the mild steel surface. The test results showed that the complex and ligand are mixed-type inhibitors and the compounds are adsorbed on the steel surface according to Temkin adsorption isotherm. The inhibition efficiency of the inhibitors follows the trend Co-bipy > bipy. The adsorption of the inhibitors can be classifies as physical adsorption.  相似文献   

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