Laboratory-based X-ray Absorption Spectrometer

X射线吸收光谱(XAS)能够研究复杂材料体系特定元素的原子级结构，并提供与X射线衍射或电子显微镜等其他技术高度互补的结构信息。目前，测量几乎完全在同步辐射光源上进行，因为它们需要可变能量和高强度的单色X射线。然而，进入这些大型设施的途径受到限制，规划和执行实验的时间尺度很长。然而，由于最新的技术进步，第一批基于实验室的XAS光谱仪现在可以商业化使用。因此，2019年初被任命为莱比锡大学正教授的申请人计划建设一个XAS实验室，作为她新成立的团队的核心实验设施，以所请求的光谱仪为基石。申请人和她的团队多年来已经密集应用XAS，以研究复杂半导体中局部元素特定结构与重要材料性质之间的相关性。一台功能强大、用途广泛的实验室XAS光谱仪将能够确定黄铜矿、钾锌矿和其他硫化物的原子级结构，这些硫化物被用作高效薄膜太阳能电池的吸收体或热电材料，也可以用于其他有希望的材料系统，如CuI基半导体，这将在DFG研究单位2857的框架内进行研究。除了在众多研究项目和合作中的应用外，该光谱仪还将用于推动目前国际上基于实验室的XAS技术和方法的发展。通过系统地评估光谱仪在实际研究应用中的能力和局限性，将提出进一步发展的新方法。已经计划以低温样品环境的形式对光谱仪进行第一次扩展，并且是本申请的一部分。此外，基于实验室的XAS光谱仪为学生提供了更容易地介绍XAS的可能性，使他们能够参与最先进的分析技术，从而为以研究为导向的教学提供宝贵的动力。因此，不仅在同步加速器上进行XAS测量的能力，而且在该小组自己的实验室中进行现场测量的能力，对于莱比锡大学这个新小组的成功建立、发展和未来的工作都是绝对必要的。

X-ray absorption spectroscopy (XAS) enables the investigation of the element-specific atomic-scale structure of complex material systems and provides structural information highly complementary to that obtained by other techniques such as X-ray diffraction or electron microscopy. Currently, the measurements are performed almost exclusively at synchrotron radiation sources since they require monochromatic X-rays of variable energy and high intensity. The access to these large-scale facilities is restricted though and long time scales arise for planning and performing experiments. Thanks to the most recent technological progress, however, the first laboratory-based XAS spectrometers are now available commercially. Therefore, the applicant, who was appointed full professor at the University of Leipzig at the beginning of 2019, plans to build a XAS Laboratory as core experimental facility of her newly founded group with the requested spectrometer as the foundation stone.The applicant and her group have already applied XAS intensively for many years to investigate the correlation between local element-specific structure and important material properties in complex semiconductors. A powerful and versatile laboratory-based XAS spectrometer will enable the determination of the atomic-scale structure of chalcopyrites, kesterites and other chalcogenides, used as absorbers in high-efficiency thin film solar cells or as thermoelectrics, but also of other promising material systems such as CuI-based semiconductors, which are investigated in the framework of the DFG Research Unit FOR 2857. Apart from the application in numerous research projects and collaborations, the spectrometer will be used to advance the current technical and methodical development of laboratory-based XAS on an international level. By systematically evaluating the capabilities and limitations of the spectrometer in real-life research applications, new approaches for further developments will be proposed. A first extension of the spectrometer in the form of a cryogenic sample environment is already planned and part of the present application. Moreover, a laboratory-based XAS spectrometer provides the possibility to introduce students much more readily to XAS, to involve them in state-of-the-art analytical techniques and thus to provide valuable impulses for a research-oriented teaching. The capability to perform XAS measurements not only at a synchrotron but also on site in the group’s own laboratory is therefore absolutely essential for the successful establishment, growth and future work of this new group at the University of Leipzig.