Study on γ-Aminopropyltrimethoxysilane Films on Transition Metal Surfaces

本文对在过渡金属铁、镍电极表面制备得到的γ-氨丙基三甲氧基硅烷(γ-APS)膜进行了研究。实验中对硅烷膜用X-射线光电子能谱(XPS)、现场表面增强拉曼散射光谱(SERS)和原子力显微镜(AFM)进行了表征。X-射线光电子能谱(XPS)的结果发现存在两个N1s峰,表明γ-APS膜中的氨基有两种存在方式:自由氨基和质子化氨基。实验中还发现现场表面增强拉曼散射光谱(SERS)是研究金属/γ-APS体系中界面层结构非常有效的手段,SERS结果表明硅醇羟基和氨基发生了竞争吸附,且γ-APS分子在外加电位等条件的影响下吸附状态会发生一定变化。原子力显微镜(AFM)的表征结果在微观上显示电极表面的γ-APS膜上形成了一种较规则的微孔结构,这种结构可能与基底的性质有关。The films of γaminopropyltrimethoxysilane (γAPS) prepared on transition metal(iron and nickel electrode) surfaces were studied. The silane films were characterized by Xray photoelectron spectroscopy (XPS), insitu Surfaceenhanced Raman spectroscopy (SERS), atom force microscopy (AFM). XPS results of γAPS modified electrodes showed the presence of two nitrogen binding energy peaks indicating the presence of the amine in two different states, the free amine and the protonated state. It has been found that the insitu surfaceenhanced Raman spectroscopy are useful for diagnosing the structure of the γAPS/metal interface. Results of SERS indicated that the silanol and amino groups adsorbed competitively on the metal surfaces. At the same time, the electrode potential has great influence on the nature of adsorption of these head groups. The films of γAPS on electrode surfaces was characterized by atom force microscopy and showed a kind of regular porous structure on the microscopic scale, it may due to the roughness of the electrode surfaces

Study on Films of Organofunctional Silanes on Transition Metal Surfaces——The Structure of γ-Aminopropyltrimethoxysilane Films on Nickel Electrodes

在镍电极表面制备了γ 氨丙基三甲氧基硅烷膜 (γ APS)并对其形成和结构进行了研究 .镍电极表面有机官能团硅烷膜的X射线光电子能谱 (XPS)结果表明氮、硅等元素在电极表面的存在 ,并且氨基在膜中有若干种存在方式 ,包括自由氨基和质子化的氨基 .通过对表面增强拉曼散射光谱 (SERS)谱图的分析 ,发现与电极表面作用的吸附基团硅醇羟基和氨基发生了竞争吸附 ,它们及其邻近基团的拉曼谱峰随着电位的负移除了相对强度发生变化以外 ,还发生了一定的位移 ,这缘于吸附基团吸附的量和吸附取向随电极电位发生了变化并形成了更为复杂的界面结构 ;氨基不同存在方式之间也会随之发生转变 ,这一结果与X射线光电子能谱分析的结果相符合 .原子力显微镜 (AFM)结果表明镍电极表面的有机官能团硅烷膜呈现为一种较规则的多孔结构In the present paper, we prepared the γ-aminopro py ltrimethoxysilane (γ-APS) films on nickel electrode surfaces and studied their formation and structure. XPS results of the films of the organofunctional silan es modified nickel electrodes show the presence of nitrogen and silicon bindin g energy peaks indicating the presence of γ-APS on the metal surface. The result s also in dicate that the amine is presented in several different states, including the free amine and the protonated one. The potential-dependent Raman spectra gave plen ty of information of γ-APS/metal interface, the silanol and amino groups adsor bed competitively on the nickel surfaces. While the applied potential was change d negatively from open circuit potential, the peak intensity of the SERS spectra of these adsorptive groups and the adjacent groups changed and the frequencies of the bands red-shifted. It is assumed that the quantity and adsorptive orien tation of the adsorptive groups changed with the change in the potential and for med more complicated structure of interface. It was also found that the differen t states of amine transformed with the change in the potential, this can be conf irmed by the results of XPS. Atom force microscopy (AFM) was applied to characte rize the silane films. It could be concluded that the films of the organofunctio nal silanes are porous on the microscopic scale.厦门大学固体表面物理化学国家重点实验室开放课题资

Study on Raman Spectra of Several Conformations of Thiophenol on Gold

用Gaussian 98程序在B3LYP/6-311+G**(C,H,S)水平上计算得到苯硫酚(TP)的一套校正因子,对苯硫酚各频率进行了势能分布(PEDs)分析,并对各振动模式进行了详细的指认.同时,在B3LYP/6-311+G**(C,H,S)/LANL2DZ(Au)水平上优化得到苯硫酚的各种形态与金结合,即C6H5SH-Au,C6H5SAu,C6H5S--Au的平衡构型,且在此基础上得到了C6H5SH-Au,C6H5SAu,C6H5S--Au三种形态的计算拉曼谱图.其中苯硫酚金盐(C6H5SAu)的拉曼谱图与实验得到的苯硫酚在金溶胶中的谱图是一致的,由此很好地证明了TP与金形成苯硫酚金盐.The optimized geometries of the clusters C6H5SH, C6H5SAu, C6H5S--Au and C6H5SHAu were calculated using the B3LYP density functional method with the 6-311+G** basis set for C, S, H and LANL2DZ for gold. All the calculations were carried out with the Gaussian 98 program package. Through PEDs (Potential Energy Distributions) analysis, comprehensive frequency assignments of thiophenol were performed and the scaling factors of the thiophenol were found. The calculated Raman spectra of several conformations of the thiophenol adsorbed on gold were obtained. The calculated Raman spectrum of C6H5SAu is in good agreement with the experimental one. Therefore, C6H5SAu is the conformation which is closest to the reality.国家自然科学基金(Nos.20273045,20373046);; 厦门大学固体表面物理化学国家重点实验室开放课题资助项目

The Dependence of The SERS Intensities on The potential

SErS谱峰强度随电位的变化顾仁敖，吴芸，乔专虹（苏州大学化学系215006）田中群，李五湖（厦门大学化学系361005）THEdEPEndEnCEOfTHESErSInTEnSITIESOnTHEPOTEnTIAl￥gurEnAO；WuyunAnd..

The Response Rate of The SERS Intensity When A Potential Step is Applied

SErS谱峰强度对电位阶跃的响应速率顾仁敖，吴芸，乔专虹，姚建林（苏州大学化学系苏州215006）田中群，李五湖（厦门大学化学系厦门361005）THErESPOnSErATEOfTHESErSInTEnSITyWHEnAPOTEnTIAlSTEPI...Abstract Time-resolved surFace-enhanced Raman spectroscopy（TRSERS）has been combined with the potential step method to study thiourea and ClO coadsorbed at Ag electrodes.When a potential is applied， the response rate of the SERS intensity depends on the potential being stepped the stepping direc-tion, the concentration of TU and the diFFerent SERS band

The Dependence of The SERS Intensities Rate on The Potential

SErS谱峰强度比与电位的关系顾仁敖，吴芸，乔专虹，姚建林（苏州大学化学系215006）田中群，李五湖（厦门大学化学系361005）THEdEPEndEnCEOfTHESErSInTEnSITIESrATEOnTHEPOTEnTIAl￥gurEnAO...Abstract Time-resolved surFace－enhanced Raman spectroscopy （ TRSERS）has been combined with the potental step inethod to study thiourea and ClO coadsorbed at Ag electrodes.When the potential changed， iF the ratio of two SERS bands intensities were stable， the two bands must have some common properties.The two bands at 932cm--(-1) and 1094cm--(-1) have similar properties

Study on films of organofunctional silanes on transition metal surfaces - The structure of gamma-aminopropyltrimethoxysilane films on nickel electrodes

In die present paper, we prepared the gamma-aminopropyltrimethoxysilane (gamma-APS) films on nickel electrode surfaces and studied their formation and structure. XPS results of the films of the organofunctional silanes modified nickel electrodes show the presence of nitrogen and silicon binding energy peaks indicating the presence of gamma-APS on the metal surface. The results also indicate that the amine is presented in several different states, including the free amine and the protonated one. The potential-dependent Raman spectra gave plenty of information of gamma-APS/metal interface, the silanol and amino groups adsorbed competitively on the nickel surfaces. While the applied potential was changed negatively from open circuit potential, the peak intensity of the SERS spectra of these adsorptive groups and the adjacent groups changed and the frequencies of the bands red-shifted. It is assumed that the quantity and adsorptive orientation of the adsorptive groups changed with the change in the potential and formed more complicated structure of interface. It was also found that the different states of amine transformed with the change in the potential, this can be confirmed by the results of XPS. Atom force microscopy (AFM) was applied to characterize the silane films. It could be concluded that the films, of the organofunctional silanes are porous on the microscopic scale

Study on Raman spectra of several conformations of thiophenol on gold

The optimized geometries of the clusters C6H5SH, C6H5SAu, C6H5S- -Au and C6H5SHAu were calculated using the B3LYP density functional method with the 6-311+G** basis set for C, S, H and LANL2DZ for gold. All the calculations were carried out with the Gaussian 98 program package. Through PEDs (Potential Energy Distributions) analysis, comprehensive frequency assignments of thiophenol were performed and the scaling factors of the thiophenol were found. The calculated Raman spectra of several conformations of the thiophenol adsorbed on gold were obtained. The calculated Raman spectrum of C6H5SAu is in good agreement with the experimental one. Therefore, C6H5SAu is the conformation which is closest to the reality

Serrs and Electrochemical Study of Yeast Iso-1-Cytochrome c Mutant F82H

应用表面增强拉曼光谱和循环伏安法研究了细胞色素c及其突变体F82H的氧化还原性质 .结果表明苯丙氨酸对组氨酸的取代使得蛋白质结构更为稳定 .相对于原体蛋白质 ,突变体的氧化还原电位向负电位方向移动 ,这被归因于由氧化还原过程中伴随有配体转换反应影响所致 .The redox properties of iso?1?yeast cytochrome c and its mutant F82H were studied by surface?enhanced Raman spectroscopy and cyclic voltammetry. The results showed that the replacement of phenylalanine?82 with histidine led to a more stable global structure of the protein. A negative shift in the redox potential of the mutant relative to that of wild type protein is ascribed to a ligand switching reaction during the redox processes.作者联系地址：苏州大学化学系!江苏苏州215006,苏州大学化学系!江苏苏州215006,中国科学院长春应用化学研究所!吉林长春130022,Dept.of Chem.!Iowa State Univ.,Ames,IA50011,USA,Dept.of Chem.!Iowa State Univ.,Ames,IA50011,USAAuthor's Address: 1. Dept. of Chem., Suzhou Univ., Suzhou 215006, China; 2. Inst. of Changchun Applied Chem.,Chinese Academy of Sci.,Changchun 130022, China; 3. Dept.

Progress in Labeled Immunoassay Based on SERS

表面增强拉曼光谱(SERS)用于标记免疫检测是标记免疫学与SERS相结合的一门新型的研究技术。20世纪70年代,SERS现象的发现与证实给拉曼光谱技术的研究注入了新的活力。SERS因具有高灵敏度、较高选择性以及适合水溶液物质结构研究等特点,近年来已在生物医学研究领域中显示出独特的潜在应用前景。在标记免疫领域,SERS标记免疫研究更是得到了迅速的发展,成为了国内外的研究热点。文章从SERS标记免疫检测灵敏度的提高、非特异性吸附的降低、多组分检测等三方面叙述了SERS标记免疫检测的原理、特点、存在问题及最新发展。归纳了目前提高SERS标记免疫检测灵敏度的研究技术,阐述了研究中非特异性吸附带来的负面影响,简介了实验室的多组分研究工作。同时,对SERS标记免疫技术未来的研究方向与发展前景进行了展望。Labeled immunoassay utilizing surface-enhanced Raman spectroscopy (SERS) is a new-style research technology. The discovery and confirmation of surface-enhanced Raman spectroscopy have made Raman spectroscopy a powerful tool in many research fields. SERS has the advantages such as high sensibility and selectivity, also it is suitable for the study of liquid substance. In recent years, it has shown potential application future in biomedical field, and also developed fast in labeled immunoassay. The principle, specialty, problem and recent advances of labeled immunoassay based on SERS were reviewed in terms of detection limits, non-specific adsorption and multi-analyte immunoassay. The latest advancement in the improvement of detection limits was summarized, along with the introduction of some work in our lab, as well as expatiating on the effect of non-specific adsorption. Finally, the development trends and application perspectives were discussed.国家自然科学基金项目(20373046,20573076)资