MRI: Acquisition of a Nano-Infrared Spectrometer

非技术描述：材料的表面在决定其特性和性能方面起着核心作用。在从能量存储到医学再到计算的各种应用中，科学家需要了解表面的组成和结构，以解释它们的行为并改善它们的特性。这些表面包括电池内部的界面，细胞表面的蛋白质，以及新型塑料的界面。然而，理解表面和界面是一个挑战，因为表面的组成和结构可以在很小的距离内变化。这些微小的距离可能只有一米的十亿分之一，也就是纳米，这种结构可能只包含100个原子。为了克服这一挑战，通过这项主要研究仪器拨款获得的仪器，通过结合测量成分的工具（称为红外光谱）和测量纳米结构的工具，可以更深入地了解表面。由此产生的仪器被称为纳米红外光谱仪，使科学家能够详细研究许多复杂的表面。这种新的认识使许多科学和技术领域取得了重要进展。此外，该工具还为研究生、本科生和高中生（包括代表性不足群体的学生）提供了使用该工具的机会和培训。该仪器被安置在北卡罗来纳大学教堂山分校的教堂山分析纳米制造实验室（CHANL）的共享仪器设施中，该仪器为培训，教育和研究提供了动手机会。技术描述：传统的红外光谱是一种强大的工具，可以深入了解材料的组成，但其较差的空间分辨率限制了其在纳米科学和纳米技术中的应用。为了克服这一挑战，所获得的仪器将红外显微镜与原子力显微镜（AFM）结合起来，以大约10 nm的空间分辨率测量红外光谱。这种新工具可以研究异质表面的组成，例如细胞表面上蛋白质的分布或有机光伏电池的界面。这种纳米红外系统的一个显著特点是使用多个量子级联激光器作为光源。总的来说，这些激光器的工作范围从800 1/cm到3600 1/cm，这是一个非常宽的范围。这个范围有助于测量许多常见的官能团，从C-F在800 1/cm到O-H和N-H在3600 1/cm。这种新功能允许测量复杂的表面，例如电池中的电极/电解质界面，其组成在10nm长度范围内变化。辨别电池电极化学功能的空间变化的能力，将使人们对诸如降解机制等问题有更深入的了解。纳米红外光谱仪的用途超出了测量官能团的范围。例如，该仪器使等离子体纳米结构的研究成为可能，其中原子力显微镜尖端用于绘制等离子体成分的空间分布。这些不同的能力使纳米红外具有从纳米光子学到电化学再到细胞生物学的应用。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。

Non-Technical Description: The surfaces of materials play a central role in determining their properties and performance. In applications ranging from energy storage to medicine to computation, scientists need to understand the composition and structure of surfaces to explain their behavior and improve their characteristics. These surfaces include the interfaces found within batteries, the proteins on the surface of a cell, and the interfaces in new kinds of plastics. Understanding surfaces and interfaces is a challenge, however, because the composition and structure of surfaces can vary over tiny distances. These tiny distances can be just one-billionth of a meter, called a nanometer, and the structures may contain just one hundred atoms. To overcome this challenge, the instrument acquired through this Major Research Instrumentation grant is allowing far deeper insight into surfaces by combining a tool that measures composition, called infrared spectroscopy, with a tool that measures nano-sized structures. The resulting instrument, called a nano-infrared spectrometer, enables scientists to study many complex surfaces in detail. This new understanding is enabling important advances in numerous areas of science and technology. In addition, this instrument is providing graduate, undergraduate, and high school students - including those in underrepresented groups - with access to and training on the instrument. The instrument is housed in a shared instrument facility in the Chapel Hill Analytical Nanofabrication Laboratory (CHANL) at the University of North Carolina at Chapel Hill, where the instrument provides hands-on opportunities for training, education, and research. Technical Description:Traditional infrared (IR) spectroscopy is a powerful tool that provides deep insight into the composition of materials, but its poor spatial resolution has limited its applications in nanoscience and nanotechnology. To overcome this challenge, the instrument acquired combines IR microscopy with an atomic force microscope (AFM) to measure IR spectra with a spatial resolution of approximately 10 nm. This new tool allows the composition of heterogeneous surfaces to be studied, such as the distribution of proteins on the surface of cells or the interfaces in organic photovoltaics. A distinctive feature of this nano-IR system is the use of multiple quantum cascade lasers as a light source. Collectively, these lasers operate from 800 1/cm to 3600 1/cm, which is an unusually broad range. This range facilitates measurements of many common functional groups, from C-F at 800 1/cm to O-H and N-H at 3600 1/cm. This new capability is allowing complex surfaces to be measured, such as the electrode/electrolyte interface in batteries, where the composition varies on the 10-nm length scale. The ability to discern spatial variations in the chemical functionality of battery electrodes will allow fundamental insight into, for example, mechanisms of degradation. The uses of the nano-IR spectrometer extend beyond measuring functional groups. For example, the instrument is enabling studies on plasmonic nanostructures, where the AFM tip is used to map the spatial distribution of the plasmonic component. These diverse capabilities allow nano-IR to have applications that extend from nanophotonics to electrochemistry to cellular biology.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.