Total Internal Reflection Peak Force Infrared Microscopy
Total Internal Reflection Peak Force Infrared Microscopy
复制标题
全内反射峰值力红外显微镜
DOI：
10.1021/acs.analchem.0c01176
复制
发表时间：
2021
影响因子：
7.4
通讯作者：
Xu, Xiaoji G.
中科院分区：
文献类型：
--
作者：
Wang, Haomin;Wang, Le;Janzen, Eli;Edgar, James H.;Xu, Xiaoji G.
全内反射（TIR）红外光谱是一种方便的测量工具，用于收集光谱进行化学鉴定。然而，TIR红外显微镜缺乏高的空间分辨率，由于光学衍射极限和难以保持高质量的波前聚焦。在这篇文章中，我们提出了峰值力红外显微镜在TIR几何实现10 nm的空间分辨率。代替光学检测，样品的光热响应收集在原子力显微镜的峰值力轻敲模式。我们展示了两个有代表性的样品上的技术：软物质的结构聚合物和六方氮化硼片的二维材料。作为该装置的扩展，我们还演示了光诱导力显微镜的TIR激发的纳米红外成像。TIR几何结构与纳米红外显微镜的组合简化了光学对准，为基于原子力显微镜的红外显微镜提供了替代的仪器设计原理。
Total internal reflection (TIR) infrared spectroscopy is a convenient measurement tool for collecting spectra for chemical identification. However, TIR infrared microscopy lacks high spatial resolution due to the optical diffraction limit and difficulty to preserve a high-quality wave front for focus. In this article, we present the peak force infrared microscopy in the TIR geometry to achieve a 10 nm spatial resolution. Instead of optical detection, photothermal responses of the sample are collected in the peak force tapping mode of atomic force microscopy. We demonstrate the technique on two representative samples: structured polymers for soft matters and a hexagonal boron nitride flake for two-dimensional materials. As an extension of the apparatus, we also demonstrate nanoinfrared imaging with the TIR excitation for photoinduced force microscopy. The combination of TIR geometry with nanoinfrared microscopies simplifies the optical alignment, providing alternative instrument-designing principles for atomic force microscopy-based infrared microscopy.