Near-field Vibrational Imaging of Doping and Thermal Effects in Polymer Thin Films

新墨西哥大学的Terefe Habteyes将在化学系化学结构、动力学和机制a （CSDM-A）项目和刺激竞争研究（EPSCoR）项目的支持下，研究聚合物薄膜中的化学相分离、电荷定位和局部热效应，以纳米空间分辨率绘制化学非均质性，并更好地理解局部电子转移过程。散射型扫描近场光学显微镜（s-SNOM）和局部傅里叶变换红外光谱（纳米ftir）可以在~10 nm的空间分辨率下直接可视化有机膜中的化学物质。提高对载流子如何通过界面传输的理解有可能推进各种电子薄膜、光伏和显示器的制造方法。Habteyes研究小组的研究将通过与联邦政府实验室的合作得到加强。Habteyes博士和他的团队还将通过夏季外展活动吸引高中教师和学生。这个项目依赖于使用一个锋利的探针作为纳米天线，用于纳米ftir光谱和s-SNOM化学成像测量。纳米ftir光谱识别有机材料混合物中的化学物质，而s-SNOM成像则在二维上绘制化学物质。研究小组将评估有机半导体（OSCs）中的分子掺杂和电荷定位，向OSC和分子掺杂的热电子转移，以及聚合物共混物中依赖温度的分子间相互作用。通过纳米尺度空间分辨率对电荷态和化学复合物的直接观察，可以了解溶液处理和有机薄膜后处理步骤对材料制造的影响。从这项研究中获得的基本理解有可能推动聚合物材料在不同技术中的应用，如光伏、场效应晶体管、光电探测器、热电和其他新兴应用。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Chemical Structure, Dynamics, and Mechanisms-A (CSDM-A) Program in the Division of Chemistry and the Established Program to Stimulate Competitive Research (EPSCoR), Terefe Habteyes of the University of New Mexico will investigate chemical phase separation, charge localization, and localized thermal effects in polymer thin films to map chemical heterogeneity with nanometer spatial resolution and to develop a better understanding of localized electron transfer processes. Scattering-type scanning near-field optical microscopy (s-SNOM) and localized Fourier transform infrared (nano-FTIR) spectroscopy allow for the direct visualization of chemical species in organic films with ~10 nm spatial resolution. Improving the understanding of how carriers are transported across an interface has the potential to advance fabrication methods of various electronic films, photovoltaics, and displays. Research performed by the Habteyes research team will be enhanced through collaborations with federal government laboratories. Dr. Habteyes and his group will also engage high school teachers and students through summer outreach activities. This project relies on the use of a sharp probe that serves as a nanoantenna for nano-FTIR spectroscopy and s-SNOM chemical imaging measurements. Nano-FTIR spectroscopy identifies chemical species in organic material blends, while s-SNOM imaging maps the chemical species in two-dimensions. The research team will evaluate molecular doping and charge localization in organic semiconductors (OSCs), hot electron transfer to OSC and molecular dopants, and temperature-dependent intermolecular interaction in polymer blends. The direct observation of charge states and chemical complexes with nanoscale spatial resolution will inform how material fabrication is influenced as a function of solution processing and organic thin film post-processing steps. The fundamental understanding obtained from this research has the potential to advance the application of polymeric materials for different technologies such as photovoltaics, field effect transistors, photodetectors, thermoelectric and other emerging applications.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.