Correlative Mapping of Crystal Orientation and Chemistry at the Nanoscale

先进材料是大量关键现代技术的核心，从航空航天和汽车工业，到半导体，再到外科植入物。材料研究的核心是从原子尺度分析材料结构的能力，通过微观结构和单个组件和设备的尺寸。只有了解这种结构层次，才能优化器件和组件的特性和性能。透射电子显微镜（TEM）是表征各种材料的局部结构和化学性质的关键技术。可以通过成像和电子衍射图案获得有关原子排列的信息，也可以通过补充光谱测量来研究组成。TEM的最大优势之一是能够研究微小体积的材料，从而揭示有关局部缺陷和界面的信息，这些信息往往控制着现代器件和材料的宏观性能。在本提案中，我们的目标是安装一台最先进的TEM，配备专用的电子衍射相机，能够对晶体结构进行超快速和大面积的分析，工程材料、合金、陶瓷和涂层中的取向和应变。此外，新探测器的高灵敏度也将允许使用低电子剂量进行相同范围的实验。令人兴奋的是，这将为研究传统上不适合电子显微镜方法的材料的原子排列和微观结构开辟新的机会。其中包括有机材料（如聚合物、复合材料和药物）以及各种新型有机-无机杂化材料，这些材料在太阳能电池、气体储存和靶向催化等技术中显示出巨大的潜力。这一新的进展是特别重要的，因为这种有机和混合材料是难以使用传统的X射线衍射方法和有序和无序域，缺陷和界面的微观结构往往是了解这些材料。只有了解了这种结构的复杂性，我们才有希望控制和利用它们惊人的特性广度。结合这种衍射能力，将是高效的X射线光谱成分分析，允许同时分析样品的局部原子结构和化学性质。这种相关实验将允许更好地理解材料和器件的宏观行为，例如理解痕量杂质如何影响裂纹延伸穿过屏障涂层的方式，或者当混合框架材料吸收气体分子时发生的结构变化。这将包括引入先进的数据科学方法（通常称为大数据方法），以帮助处理和理解这样一个系统可以生成的大量数据。通过这种方式，将有可能解开材料结构的秘密，而这些秘密通过单独研究晶体结构或成分是不可能确定的。这种新的分析能力将与一系列原位实验方法结合使用，这些方法将使材料和设备在研究过程中受到温度、场、应力或化学侵蚀等条件的影响。通过模拟真实的操作条件，可以探索和优化材料的真实行为，以造福所有人。

Advanced materials lie at the heart of a huge number of key modern technologies, from aerospace and automotive industries, to semiconductors through to surgical implants. Central to the study of materials is the ability to analyse the structure of materials from the atomic scale, up through the microscopic structure and on to the size of individual components and devices. Only by understanding this hierarchy of structure can the properties and performance of devices and components be optimised. Transmission electron microscopy (TEM) is a key technique for characterising the local structure and chemistry of a wide range of materials. It is possible to gain information about the arrangement of atoms through imaging and electron diffraction patterns, and also to study composition via complementary spectroscopic measurements. One of the greatest strengths of the TEM is the ability to study tiny volumes of material, and hence to uncover information about the local defects and interfaces which often control the macroscopic properties of modern devices and materials.In this proposal we aim to install a state-of-the-art TEM with a dedicated electron diffraction camera that enable ultra-fast and large area analysis of the crystal structure, orientation and strain in engineering materials, alloys, ceramics and coatings. Furthermore, the high sensitivity of the new detector will also allow the same range of experiments using low electron doses. Excitingly this will open up new opportunities to study the atomic arrangement and microstructure of materials that are traditionally not suited to electron microscopy methods. These include organic materials (such as polymers, composites and pharmaceuticals) and also the variety of novel hybrid organic-inorganic materials that are showing great potential for technologies such as solar cells, gas storage and targeted catalysis. This new advance is particularly important as such organic and hybrid materials are difficult to characterise using traditional X-ray diffraction methods and the microstructure of ordered and disordered domains, defects and interfaces is often poorly understood for these materials. Only by understanding such structural complexity can we hope to control and harness their amazing breadth of properties.Combined with this diffraction capability will be high efficiency X-ray spectroscopy compositional analysis allowing the simultaneous analysis of the local atomic structure and chemistry of samples. Such correlative experiments will allow a better understanding of the macroscopic behaviour of materials and device, for example understanding how trace impurities affects the way cracks extend through barrier coatings or the structure changes that occur when hybrid framework materials absorb gas molecules. This will include the incorporation of advanced data science methods (often referred to as big-data approaches) to help process and understand the huge quantities of data that such a system can generate. In this way it should be possible to unlock secrets of material structure that would be impossible to ascertain by the isolated study of either crystal structure or composition.This new analytical power will be used in conjunction with a range of in-situ experimental methods that will allow materials and devices to be subjected to conditions such as temperature, fields, stress or chemical attack during the studies. By mimicking realistic operating conditions the true behaviour of materials can be explored and optimised for the benefit of all.