Electrochemical studies of octadecanethiol and octanethiol films on variable surface area mercury sessile drops

Octadecanethiol (ODT) and octanethiol (OT) films at the mercury-electrolyte interface are examined using cyclic voltammetry and differential capacitance measurements at a single frequency. A mercury flow-system is used to alter the volume, and therefore, the surface area and surface pressure of the mercury electrode. Manipulation of the mercury electrode's volume enables the introduction and removal of defects in the insulating thiol films. OT and ODT film behavior are contrasted under conditions of expansion and contraction. ODT forms extremely impermeable layers that allow 1000 time less redox probe current than seen on uncoated drops. Expansion of the mercury electrode to increase the electrode surface area produces defects and pinholes in the thiol film. These defects are almost completely removed when the drop is compressed back to its initial surface area. OT also forms insulating films on mercury sessile drops, however these films contain more defects than ODT films. While expansion of an OT-coated mercury drop increases redox probe current, recompression of the drop does not return the film to its initial condition. Pinholes and defects in the OT and ODT films can also be produced by cycling to negative potentials, which produce abrupt stripping peaks.     

In-situ cleaning and passivation of oxidized Cu surfaces by alkanethiols and its application to wire bonding

The treatment of oxidized Cu surfaces using an alkanethiol as a reducing agent has been investigated. Exposure to a dilute solution of 1-decanethiol resulted in the complete removal and/or conversion of CuO and subsequent formation of a passivating thiolate film, a so-called self-assembled monolayer (SAM), on the underlying Cu/Cu₂O surface as evidenced by x-ray photoelectron spectroscopy (XPS) analysis. Morphological changes, monitored by scanning electron microscopy (SEM) and atomic force microscopy (AFM), revealed transformation of the rough, porous CuO layer into a comparatively smooth Cu/Cu₂O surface. Experiments performed on integrated circuit back-end-of-line (BEOL) die structures, comprising Cu/SiO₂ bond pads used as substrates for Cu wire bonding, demonstrate the potential application of a thiol-based in-situ cleaning-passivation procedure in microelectronics.     

金属表面烷基硫醇类自组装膜的研究进展

自组装膜(SAMs)是活性分子通过化学键自发吸附在基底上的有序分子膜,由于其排列紧密、结构稳定,因此对基底金属具有良好的防腐蚀作用.本文综述了近年来烷基硫醇类自组装膜在金、铜、铁和其他金属表面缓蚀中的发展和现状.     

不同链长的烷基硫醇自组装膜在不同腐蚀介质中的抗腐蚀性阻抗研究

文章通过在铜表面上制备高质量的不同链长的烷基硫醇自组装膜并研究烷基硫醇自组装膜在不同腐蚀介质NaCl、HCl、H2SO4中的抗腐蚀能力,从而对其抗腐蚀性能进行比较研究。结果表明:铜电极上组装的C18SH、C12SH、C6SHSAMs在不同的腐蚀介质中对基底均有相当好的腐蚀保护作用;在其它条件相同的情况下,烷基硫醇的碳链越长,自组装膜对铜基底的腐蚀保护能力越强。     

Interaction of the Adhesive Protein Mefp-1 and Fibrinogen with Methyl and Oligo (Ethylene Glycol)-terminated Self-assembled Monolayers

The interaction of fibrinogen and Mefp-1, the adhesive protein of the common blue mussel Mytilus edulis, with methyl- and oligo(ethylene oxide) (OEG)-terminated self-assembled monolayers (SAMs) has been investigated by Fourier Transform Infrared Reflection (FT-IRAS) analysis. The measurements on the hydrophobic surfaces show that the underlying SAM is structurally undisturbed when the proteins adhere. Mefp-1 is used as an attachment factor (Cell-Tak^TM) in cell cultures and in biomedical applications, and it is of interest to determine if OEG-terminated surfaces are inert towards Cell-Tak-mediated cell adhesion. We find that, when Langmuir transfer of a protein film at the liquid/air interface is avoided, the moderately hydrophilic hydroxyhexa (ethylene oxide) and methoxytri(ethylene oxide) undecanethiolate SAMs prepared on Au substrates are protein resistant. The inertness of the OEG-terminated surfaces does not depend on any specific protein present in solution, but rather appears to be a general phenomenon that is independent of the specific structure or chemistry of the macromolecule.     

金-烷基硫醇的自组装及其聚合物基复合材料的介电性能

采用简单的水溶液法自组装合成了金的十二烷基硫醇纳米粒子,并用透射电子显微镜(TEM)对其微观结构形貌进行观察,发现形成一种核壳结构材料(记为Au@S-R12).红外光谱(IR)证实烷基硫醇有机层已与金核相连.X射线光电子能谱分析(XPS)表明金的表面已附着了硫元素.同时还对其热性能和光性能分别做了热失重分析(TGA)和紫外-可见光谱测试.通过溶液浇注和热压成型工艺制备了Au@S-R12/聚合物复合材料,并对其介电性能进行分析,结果表明:Au@S-R12/PS复合材料在低频时具有超高的介电常数,这归因于烷基硫醇有机层有良好的电子阻隔性.     

The relationships between interfacial friction and the conformational order of organic thin films

This report describes studies of the relationships between the structures of organic monolayers and their molecular-scale frictional properties. Several distinct self-assembled monolayers (SAMs) were formed by the adsorption of a series of spiroalkanedithiols and a single structurally related normal alkanethiol. Measurements of hexadecane wettability, infrared vibrational spectroscopy, and X-ray photoelectron spectroscopy revealed that the films possessed a wide range of interfacial structures and conformational orders. Atomic force microscopy was used to measure the frictional properties of the well-characterized SAMs on the molecular scale. Comparison of the frictional data with structural information derived from complementary analytical techniques revealed a high correlation between the conformational order of the films and the observed frictional response.     

不同链长烷基硫醇自组装膜对银的防变色作用

将不同链长的烷基硫醇溶于乙醇,在银表面制备自组装膜。采用接触角测试、电化学试验、加速变色试验和X射线光电子能谱(XPS)等方法来表征自组装膜的性能。结果表明:十二烷基硫醇(DT)、十六烷基硫醇(HDT)和十八烷基硫醇(ODT)都可以在银表面形成疏水性的自组装膜,对基体腐蚀起到良好的保护作用;ODT自组装膜的致密性最好,而HDT自组装膜的防变色效果最好。     

SnCl2/RSH: a versatile catalytic system for the synthesis of 4-alkylsulfanyl-indazole derivatives

The treatment of alkylated nitro derivatives of indazole with stannous chloride in alkanethiol gave after coupling of the obtained amines with 4-methoxybenzenesulfonyl chloride in pyridine the new N-(4-alkylsulfanylindazol-7-yl)-4-methoxybenzene sulfonamides via the nucleophilic substitution of hydrogen in position 4 of indazole, together with the expected 4-methoxy-N-(indazol-7-yl)-benzenesulfonamides. All the newly synthesized compounds have been characterized by elemental analysis and spectroscopic data.     

Interaction of the Adhesive Protein Mefp-1 and Fibrinogen with Methyl and Oligo (Ethylene Glycol)-terminated Self-assembled Monolayers

The interaction of fibrinogen and Mefp-1, the adhesive protein of the common blue mussel Mytilus edulis, with methyl- and oligo(ethylene oxide) (OEG)-terminated self-assembled monolayers (SAMs) has been investigated by Fourier Transform Infrared Reflection (FT-IRAS) analysis. The measurements on the hydrophobic surfaces show that the underlying SAM is structurally undisturbed when the proteins adhere. Mefp-1 is used as an attachment factor (Cell-Tak^TM) in cell cultures and in biomedical applications, and it is of interest to determine if OEG-terminated surfaces are inert towards Cell-Tak-mediated cell adhesion. We find that, when Langmuir transfer of a protein film at the liquid/air interface is avoided, the moderately hydrophilic hydroxyhexa (ethylene oxide) and methoxytri(ethylene oxide) undecanethiolate SAMs prepared on Au substrates are protein resistant. The inertness of the OEG-terminated surfaces does not depend on any specific protein present in solution, but rather appears to be a general phenomenon that is independent of the specific structure or chemistry of the macromolecule.