Mixed azide-terminated monolayers: A platform for modifying electrode surfaces
Mixed azide-terminated monolayers: A platform for modifying electrode surfaces
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DOI：
10.1021/la052947q
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发表时间：
2006-03-14
期刊：
影响因子：
3.9
通讯作者：
Chidsey, CED
中科院分区：
文献类型：
--
作者：
Collman, JP;Devaraj, NK;Chidsey, CED
我们在金电极上制备了叠氮基硫醇和各种官能化硫醇的混合自组装膜。在铜（I）催化剂的存在下，这些叠氮化物改性的表面显示出快速和定量的反应与末端乙炔形成1，2，3-三唑。通过“点击”化学反应。初始叠氮取代基可以使用掠角红外（IR）和X射线光电子能谱来识别和监测。乙炔具有氧化还原活性的二茂铁取代基与叠氮化物封端的混合SAM和电化学测量的二茂铁修饰的SAM电极反应已被用来量化的氧化还原中心连接到这些平台。时间分辨电化学测量使我们能够跟踪这些二茂铁中心的形成，从而测量表面“点击”反应的速率。在最佳条件下，这种良好的二级反应发生，速率常数为1 × 10（3）M-1 s（-1）。使用微摩尔浓度的乙炔实现几分钟的典型反应时间。这些技术已被用来构建良好的表征，共价修饰的单层，可以用作功能电极表面。
We have prepared and characterized mixed self-assembled monolayers (SAM) on gold electrodes from azido alkane thiols and various -functionalized alkane thiols. In the presence of copper(l) catalysts, these azide-modified surfaces are shown to react rapidly and quantitatively with terminal acetylenes forming 1,2,3-triazoles. via "click" chemistry. The initial azide substituents can be identified and monitored using both grazing-angle infrared (IR) and X-ray photoelectron spectrosopies. Acetylenes possessing redox-active ferrocene substituents react with the azide-terminated mixed SAMs and electrochemical measurements of the ferrocene-modified SAM electrodes have been used to quantify the redox centers attached to these platforms. Time-resolved electrochemical measurements have enabled us to follow the formation of these ferrocene centers and thus to measure the rate of the surface "click" reaction. Under optimal conditions this well-behaved second-order reaction takes place with a rate constant of 1 x 10(3) M-1 s(-1). Typical reaction times of several minutes were realized using micromolar concentrations of acetylene. These techniques have been used to construct well-characterized, covalently modified monolayers that can be employed as functional electrode surfaces.