Probing adhesion forces at the molecular scale
Probing adhesion forces at the molecular scale
复制标题
在分子尺度上探测粘附力
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
T. Michalske
中科院分区：
文献类型：
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作者：
R. C. Thomas;J. Houston;R. Crooks;Taisun Kim;T. Michalske
在分子尺度上测量粘附力，如这里讨论的那些，是必要的，以了解宏观边界层行为，如粘附，摩擦，磨损，润滑和许多其他重要现象。作者最近的界面力显微镜（IFM）的研究提供了详细的信息，自组装单层（SAM）膜和底层基板的机械响应。此外，他们最近证明了IFM对于研究这种薄膜的化学性质是有用的。在这次演讲中，作者讨论了一种使用IFM研究表面相互作用和化学反应的新方法。为了定量测量两个有机薄膜之间的粘附力和键能的工作，他们修改了Au基板和Au探针与自组装有机硫醇分子具有相同或不同的端基（-CH{sub 3}，-NH{sub 2}，和-COOH），然后分析力与位移曲线（力的配置文件），从接近两个表面的接触。他们的研究结果表明，甲基-甲基相互作用之间的粘附力的大小与货车德瓦尔斯计算使用Lifshitz理论和以前的实验确定的值非常一致。此外，测得的峰值粘附力与预期的货车德瓦尔斯、更多的氢键和酸碱相互作用一样。«少
Measurements of adhesion forces at the molecular scale, such as those discussed here, are necessary to understand macroscopic boundary-layer behavior such as adhesion, friction, wear, lubrication, and many other important phenomena. The authors` recent interfacial force microscopy (IFM) studies have provided detailed information about the mechanical response of both self-assembled monolayer (SAM) films and the underlying substrates. In addition, they recently demonstrated that the IFM is useful for studying the chemical nature of such films. In this talk, the authors discuss a new method for studying surface interactions and chemical reactions using the IFM. To quantitatively measure the work of adhesion and bond energies between two organic thin films, they modify both a Au substrate and a Au probe with self-assembling organomercaptan molecules having either the same or different end groups (-CH{sub 3}, -NH{sub 2}, and -COOH), and then analyze the force-versus-displacement curves (force profiles) that result from the approach to contact of the two surfaces. Their results show that the magnitude of the adhesive forces measured between methyl-methyl interactions are in excellent agreement with van der Waals calculations using Lifshitz theory and previous experimentally determined values. Moreover, the measured peak adhesive forces scale as expected for van der Waals,more » hydrogen-bonding, and acid-base interactions.« less