钒氧酞菁分子沉积自组膜电极的组装及其对肼的电催化研究

由于单层修饰电极具有组装有序、定向、密集、完好及可在分子水平上控制电极表面的微结构等特点,因此它特别适于电化学基础理论研究和应用［１～３］．但由于含有巯基的可用于单层组装的化合物,常用的功能尾端仅仅限于羧基、氨基和羟基几种,大大限制了该类单层电极的应...     

4-[2-(4-N,N-二甲基苯胺基)乙烯基]吡啶氧化物的电化学行为

半菁染料是人们制造ＬＢ膜的材料之一．近年来,为得到电导率较高的薄膜,电荷转移络合物的ＬＢ膜受到重视［１］．实验证明,有机材料的ＬＢ膜经化学修饰或改性以后,电导率大大增加．化学工作者常将有机染料分子用来修饰电极,在光电化学、电催化等方面有较好的效果,因而,受到人们极大的关注．化学工作者已成功地制备出许多染料化学修饰电极,研究膜修饰电极的电化学行为［２,３］,而用循环伏安法和光谱技术对有机染料的电化学行为研究得较少［４,５］．本文对４ ［２ (４ Ｎ,Ｎ 二甲基苯胺基 )乙烯基］吡啶氧化物这个新改性的半菁化…     

自组装超分子膜修饰电极的研制及分析应用

阐述了自组装超分子膜修饰电极的发展概况及超分子体系形成的理论基础，并对自组装超分子膜修饰电极的特点、电化学行为、功能膜的制备和表征方法以及它在电催化、生物传感器、离子选择性电极等方面的应用进行了综述。     

甲基丙烯酸3-磺酸钾丙酯-苯乙烯共聚物与N,N,N-三甲基十六烷基溴化铵相互作用研究

两亲分子由于具有自组装性质,如表面活性剂分子自组装形成胶束,囊泡,天然的磷脂分子自组装形成脂质体,继而参于生物膜的形成,这是大家所熟悉的．高分子两亲分子尤其是两亲性两嵌段高分子具有自组装性质,并形成规整性好的聚集体［１～３］．聚电介质 表面活性剂体系...     

甲基丙烯酸3—磺酸钾丙酯—苯乙烯共聚物与N,N,N—三甲基十六烷基化铵相 …

两亲分子由于具有自组装性质,如表面活性剂分子自组装形成胶束,囊泡,天然的磷脂分子自组装形成脂质体,继而参于生物膜的形成,这是大家所熟悉的．高分子两亲分子尤其是两亲性两嵌段高分子具有自组装性质,并形成规整性好的聚集体［１～３］．聚电介质表面活性剂体系...     

原位光谱电化学技术对有机染料分子电极过程的研究

原位光谱电化学技术对有机染料分子电极过程的研究①唐寅轩杨杭生沈报恩＊（杭州大学化学系杭州３１００２８）有机染料分子修饰电极在光电化学，电催化等方面的应用均有较好的效果，因而受到人们极大的注意．近年来已经制备成功许多染料化学修饰电极［１］．原位光谱电化...     

3,4-二羟基苯甲酸在自组装结构中的电化学行为

电极与有确定取向的电活性基团之间的电子传递是电化学领域的研究热点．利用二维有序薄膜固定电活性官能团是一个成熟的方法［１］,主要包括ＬＢ技术和自组装技术,这两者都存在着样品合成困难的问题．近年来,通过表面逐层反应来固定电活性官能团已有研究,但是反应过程...     

L-半胱氨酸和胱胺共自组装膜活体检测抗坏血酸

自组装单分子膜（SAM）由于其独特的物理化学性质近年来受到了极大的关注. SAM通过金硫键在电极表面形成高度有序的单分子膜,该稳定的分子膜不仅可以调节表面的亲疏水性质,而且可以促进电极表面氧化还原活性分子的反应速率. 本论文提出了一种简单有效的方法,在金微电极上构建半胱氨酸和胱胺共自组装单分子膜用于活体内抗坏血酸的检测. 研究发现,当混合单分子层中半胱氨酸和胱胺的摩尔比为1:1时,可以在低电位下（约为0.10 V）显著增强抗坏血酸氧化的电子转移动力学,同时该膜能在一定程度上抵抗蛋白质在电极表面的非特异性吸附. 将共自组装单分子膜应用到活体检测中,作者检测到鼠纹状体中抗坏血酸的基准值为257±30mmol·L^-1（n = 3）. 本论文为活体电化学检测提供了一种简单、有效的方法.     

表面活性剂作用下谷胱甘肽单分子膜的离子门响应

将谷胱甘肽自组装在金电极表面,在表面活性剂存在下,以铁氰化钾及苯醌作为探针,用循环伏安法研究了修饰在金电极表面的谷胱甘肽单分子膜的电化学行为。实验发现在阳离子表面活性剂作用下,谷胱甘肽膜存在离子门行为,修饰电极表面的电子传输随阳离子表面活性剂浓度的增加而增加。阴离子表面活性剂对氧化还原探针在修饰电极上的电化学响应显示出一定的抑制作用。     

荧光特性双层自组装膜电极及电化学性能研究

以半胱胺酸为中介,利用荧光试剂1＿萘胺二乙酸钠(NADA)和DL＿半胱胺酸(Cys)的静电吸引作用,将荧光试剂NADA间接组装在金电极表面,形成自组装双层膜电极NADA/Cys/Au,该双层膜电极对金属离子具有荧光识别和电化学传感功能,本文着重研究了双层膜电极NADA/Cys/Au的电化学性能,并将其用于超痕量铜离子和镍离子的电化学分析连续测定.     

The Molecular Recognition Characteristics of ω-MercaptoMethoxy Poly(Ethylene Glycol) Self-assembled Monolayer at Gold Electrode and the Detection of Dopamine in Serum

Recently,theselfassembledmonolayersofto-mercaPtocarboxylicacidongoldelectrodeswereusedasameanstodetectDAinthepresenceofAA.l-2DAhasagoodresponseatthenegativelychargedSAMselectrodebutAAhaslittleresponseonit.InthespaPer,wehaveaPpliedto-mercaPtomethoxypoly(ethyleneglycol)(MPEG)ongoldelectrodesurfacetoformselfassembledmonolayerswithmolecularrecognitionproperty.DAhadgoodresponseatthiselectrode.However,AAwasrepelledfromtheMPEGfilm.ThsfilmelectrodecanbeusedtodetectDAintliepresenceofhighcon…     

Blocking behavior of self-assembled monolayers on gold electrodes

Self-assembled monolayers (SAMs) with metal electrodes, especially thiols on gold, are the subject of this investigation because of the unique properties of SAM-modified surfaces. Normal alkanethiols are used to modify the surface of a conventional gold electrode to block certain ions such as Pb(II) and Cu(II) from the surface of the electrode. Normal alkanethiols are also used to study the SAM-gold interfacial adsorption-desorption behavior of the self-assembled monolayer. The effects of varying chain length of SAMs, varying concentration of the alkanethiol solutions, immersion time of the pure gold electrode in the SAM solution, and the stability of a SAM-modified gold electrode in fresh chloroform are investigated using the oxidation-reduction peaks of gold. Conditions that optimize the surface coverage and the uniformity of the SAMs have been determined. Normal alkanethiols proved to be a good insulator on the electrode surface. Received: 16 January 1997 / Accepted: 4 March 1997     

Study on self-assembled monolayer of functionalized thiol on gold electrode forming capacitive sensor for chromium(VI) determination

A capacitive sensor based on S-{12-[1-(pyridin-4-ylmethyl)-1H-1,2,3-triazol-4-yl]dodecyl} ethanethioate (FT), a compound with a functional group exhibiting selective affinity towards Cr(VI) ions, was developed. FT was mixed with shorter-chain thiol-decanethiol (DT), to obtain an Au electrode surface well covered by a thiol monolayer. The composition and high quality of self-assembled monolayers (SAMs) were crucial factors influencing the performance of the capacitive sensor. In this work, SAMs formed from FT and DT mixtures with different compositions were studied. For physicochemical characterization of SAMs X-ray photoelectron spectroscopy (XPS), contact angle measurements as well as atomic force microscopy (AFM) were used. Cyclic voltammetry was employed to estimate an electrode surface coverage. Based on the obtained results, the composition of thiol layer providing the best parameters for capacitive sensing of chromium(VI) was chosen. Moreover, the analytical performance of sensor was verified.

     

若干多氮硒杂环化合物在金表面的自组装及其电化学性质

研究了1,2,5-硒二唑并[3,4-b]吡啶（SPb）,1,2,5-硒二唑并[3,4-d]嘧啶-7-（5H,6H）酮（SPO）,1,2,5．硒二唑并[3,4．d]嘧啶-5,7-（4H,6H）二酮（SPDO）等多氮硒杂环化合物在溶液中及其在金表面的自组装单分子膜的电化学性质。以Fe（CN）6^3-/4-为离子探针,利用CV法观察了Fe（CN）6^3-/4-氧化还原峰的变化。结果表明,在溶液中,电极过程主受吸附控制;自组装膜的电化学信号与其溶液相似,在-600mV左右都有一还原峰,表明该类化合物有相似的组装模式,其中SPO和SPDO在金表面形成了致密的单分子膜,有效地封闭了表面与溶液之间的电子交换和传递。     

Self-assembly of [60]fullerene-thiol derivatives on mercury surfaces

Herein we report the first self-assembly of fullerene-thiol conjugates (1 and 2) on thin mercury films (TMF) deposited on a glassy carbon electrode (GCE). The fullerene-containing SAMs were investigated by cyclic voltammetry and water contact angle measurements. Two reversible, surface-confined redox couples were obtained for the fullerene-containing SAMs on TMF/GCE in CH(2)Cl(2) solution. The surface coverage of both fullerene derivatives 1 and 2 on TMF/GCE was measured to be in the range of (1.7-1.8) x 10(-10) mol cm(-2). Both SAMs of 1 and 2 partially blocked the electron transfer across the electrode in aqueous solution. The contact angle measurements performed on TMFs clearly showed an enhancement of the surface hydrophobicity upon formation of the fullerene-containing monolayer.     

Orientation of 6-mercaptopurine SAMs at the silver electrode as studied by Raman mapping and in situ SERS

Self-assembled monolayers (SAMs) of 6-mercaptopurine (6MP) on a silver electrode in acid and alkaline media were investigated by a combination protocol of the SERS technique with Raman mapping, and it was found that the adsorption mode of 6MP SAMs changed with the pH value of the environment. Quantum calculations for the vibrational mode were performed by the BLYP/6-31G method. 6MP was adsorbed on the silver electrode with a tilted orientation via S, N1, and N7 atoms in acid medium, while the SAMs adopted head-on adsorption modes with the S atom and the N1 atom anchoring the silver surface in alkaline medium. However, 6MP SAMs turned to the same upright orientation on the electrode through the S and N7 atoms when either acid or basic solution was removed. Stability of 6MP SAMs was observed by in situ SERS spectroelectrochemical measurements. The results reveal that the desorption potentials of 6MP SAMs formed under acid and alkaline conditions from the Ag electrode were at ca. -1.3 V and -1.6 V vs SCE, respectively.     

Nanostructured gold colloid electrode based on in situ functionalized self-assembled monolayers on gold electrode

A novel method for fabricating nanostructured gold colloid electrode based on in situ functionalization of self-assembled monolayers (SAMs) of 4-aminothiophenol (4-ATP) on gold electrode is proposed. The in situ functionalization of 4-ATP SAMs yields a redox active monolayer of 4′-mercapto-N-phenylquinone diimine (NPQD). When the amino-rich surface is exposed to gold colloid, the citrate-stabilized gold nanoparticles (GNPs) can be anchored onto the surface of the in situ functionalized electrode by the electrostatic interactions and a new nanostructured gold colloid surface was obtained. The mixed monolayers of in situ functionalized product, NPQD, and 1,4-benzenedimethanethiol (BDMT) can provide a more compact and order platform to fabricate GNPs on the electrode surface. The film formed by this technique has the advantages of high organization and uniformity, which could provide a desirable microenvironment to assemble GNPs and facilitate the concentration of the analyte from the bulk solution to the electrode surface. The nanostructured gold colloid electrode has favorable effect on the electrochemical oxidation of naphthol isomers.     

Electrochemical Studies of Chemically Modified Nanometer‐Sized Electrodes

Self‐assembled monolayers (SAMs) of 4‐aminothiophenol (4‐ATP) has been successfully deposited onto nanometer‐sized gold (Au) electrodes. The cyclic voltammograms obtained on a 4‐ATP SAMs modified electrode show peaks and the peak height is proportional to the scan rate, which is similar to that on an electroactive SAMs modified macro electrode. The electrochemical behavior and mechanism of outer‐sphere electron transfer reaction on the 4‐ATP SAMs modified nanometer‐sized electrode has also been studied. The 4‐ATP SAMs modified electrode is further modified with platinum (Pt) nanoparticles. Electrochemical behaviors show that there is electrical communication between Pt nanoparticles and Au metal on the Pt nanoparticles/4‐ATP SAMs/Au electrode. However, scanning electron microscopic image shows that the Pt nanoparticles are not evenly covered the electrode.     

Anion templated surface assembly of a redox-active sensory rotaxane

Anion templation is used to assemble novel redox-active bis-ferrocene functionalised rotaxane self-assembled monolayers (SAMs) on to gold electrode surfaces; after template removal, the unique SAM rotaxane binding domain is capable of selectively sensing chloride ions electrochemically.     

Synthesis and self-assembly of thio derivatives of calix[4]arene on noble metal surfaces

Self-assembled monolayers (SAMs) provide a simple route to functionalize electrode surfaces with organic molecules. Herein we use cavity-containing derivatives of calix[4]arenes in SAMs. Bound to noble metal surface, the assembled molecules are candidates to serve as molecular sieves for H 2 molecules and H (+) ions, which could have relevance for fuel cell applications. Tetra- O-alkylated calix[4]arenes with thiolacetate and thiolamide wide-rim anchoring groups in cone and partial-cone conformations were designed, synthesized and self-assembled onto Au, Pt, and Pd surfaces. The resulting SAMs were systematically examined. Single crystal X-ray diffraction of 5,11,17,23-tetrakis(thioacetyl)-25,26,27,28-tetra- i-propoxycalix[4]arene confirmed the cone conformation and revealed the cavity dimensions of the SAMs that were formed by immersing noble metal substrates (Au, Pt and Pd deposited on Si-wafers) in solutions of calix[4]arenes. Surface characterization techniques including ellipsometry, cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS) were used, indicating that the metal surface is terminated with a monomolecular layer. Experimental thicknesses obtained from the ellipsometry are consistent with the calculated values. CV results showed 50 to 80% physical passivation against the Fe(CN) 6 (3-/4-) couple, implying an overall relatively low concentration of defects and pinholes in the films. The binding energies of the S2p core level in the XPS were consistent with the literature values and revealed that up to 3.2 out of four anchoring groups were bonded to the noble metal surface.