Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
Langmuir. 2023 Mar 28;39(12):4274-4281. doi: 10.1021/acs.langmuir.2c03222. Epub 2023 Mar 19.
It is commonly accepted that during conductive atomic force microscopy (CAFM) measurement in ambient, a liquid meniscus can form between the tip and the sample. Such a liquid bridge, normally assumed to be composed of water, is a major factor in analyzing and understanding CAFM results. Here, we show that the adsorption of adventitious hydrocarbons from the air to a surface can greatly affect CAFM data both in imaging mode and in local spectroscopy (current-voltage or - curves). We propose a model to explain the phenomena whereby hydrocarbon contaminates contribute to the composition of the liquid bridge between the tip and the sample.
人们普遍认为，在环境下进行导电原子力显微镜（CAFM）测量时，尖端和样品之间会形成液滴。这种通常被认为由水组成的液体桥是分析和理解 CAFM 结果的主要因素。在这里，我们表明，空气中的杂质碳氢化合物吸附到表面上会极大地影响 CAFM 在成像模式和局部光谱（电流-电压或 - 曲线）中的数据。我们提出了一个模型来解释这种现象，即碳氢化合物污染物有助于解释尖端和样品之间液体桥的组成。
