Standoff and Point Detection of Thin Polymer Layers Using Microcantilever Photothermal Spectroscopy
Standoff and Point Detection of Thin Polymer Layers Using Microcantilever Photothermal Spectroscopy
复制标题
使用微悬臂梁光热光谱法对薄聚合物层进行间距和点检测
DOI：
10.1149/1945-7111/ac5657
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发表时间：
2022
影响因子：
3.9
通讯作者：
Thundat, Thomas
中科院分区：
文献类型：
--
作者：
Zhao, Yaoli;Chakraborty, Patatri;Stavinski, Nicholas;Velarde, Luis;Maheshkar, Vaishali;Dantu, Karthik;Phani, Arindam;Kim, Seonghwan;Thundat, Thomas
基于光谱学的锡离子检测是一种有吸引力的方法，用于以非常高的分子选择性远距离识别材料。锡光谱可以用于要求苛刻的实际应用，如分类塑料回收。在这里，我们展示了选择性和敏感的对峙检测的聚合物薄膜，使用双材料的荧光光谱为基础的光热光谱。我们证明，该技术的选择性是足以区分各种聚合物。我们还展示了在原位，点检测薄层的聚合物沉积在双材料的悬臂梁使用光热光谱。与通过点检测、FTIR和FTIR-ATR获得的那些的间隔光谱的比较显示峰的相对加宽。聚合物暴露于UV辐射（365 nm）揭示了光谱峰不随暴露时间改变，但导致峰加宽，背景悬臂梁响应总体增加。通过优化双材料悬臂梁的热灵敏度和增加撞击在悬臂梁上的光子数量，可以进一步提高该技术的灵敏度。
Standoff detection based on optical spectroscopy is an attractive method for identifying materials at a distance with very high molecular selectivity. Standoff spectroscopy can be exploited in demanding practical applications such as sorting plastics for recycling. Here, we demonstrate selective and sensitive standoff detection of polymer films using bi-material cantilever-based photothermal spectroscopy. We demonstrate that the selectivity of the technique is sufficient to discriminate various polymers. We also demonstrate in situ, point detection of thin layers of polymers deposited on bi-material cantilevers using photothermal spectroscopy. Comparison of the standoff spectra with those obtained by point detection, FTIR, and FTIR-ATR show relative broadening of peaks. Exposure of polymers to UV radiation (365 nm) reveal that the spectral peaks do not change with exposure time, but results in peak broadening with an overall increase in the background cantilever response. The sensitivity of the technique can be further improved by optimizing the thermal sensitivity of the bi-material cantilever and by increasing the number of photons impinging on the cantilever.