In situ study of diffusion-controlled phase formation and grain growth in functional Heusler/perovskite materials using multimodal synchrotron-based techniques

具有特定性质的材料的合成通常需要在高温下在固态下的扩散控制过程。扩散过程使得能够形成具有限定组成的特定相或具有特定结构顺序的材料或促进晶粒生长。这种扩散过程的产物通常在环境条件下非原位表征。如果合成路线仍然是未知的，合成参数的调查成为一个迭代的试错循环。这就是我们的项目的用武之地，因为它依赖于在无机功能材料的合成和生长过程中对扩散过程的直接原位监测。由于避免了多组分体系合成的反复试错实验，我们的研究将有效地节省宝贵的资源，甚至可能加速新材料的发现。为此，该项目追求两个方向：（1）使用基于同步加速器的技术在高温下原位监测复杂多组分材料的相形成和晶粒生长;（2）实施多峰分析方法，优化基于“机器学习”的数据解释。我们将专注于具有强性能关系的功能无机材料，即金属间Heusler合金和氧化物双钙钛矿，两者都具有高自旋极化。我们使用这些作为模型系统来研究无序现象及其纳米颗粒（NP）在碳纳米管（CNT）中的生长。申请人Ana Guilherme Buzanich博士（BAM）和Sabine Wurmehl博士（IFW）提供的化学，物理和材料科学专业知识的结合将有助于通过不同的科学观点和技能使该项目取得成功。该项目提供了两个非常有吸引力的博士项目，因为它结合了合成开发前沿的化学和高质量的多模态分析技术，这将使两名博士生对跨学科方法学有广泛的了解。我们的研究结果将提供给物理材料科学的研究人员，可以立即应用于催化，能源相关材料和其他功能材料。

The synthesis of a material with specific properties often requires a diffusion-controlled process in the solid state at elevated temperatures. The diffusion process enables the formation of a certain phase with a defined composition or a material with a certain structural order or promotes grain growth. The products of such a diffusion process are usually characterized ex situ under ambient conditions. If the synthesis route is still unknown, the investigation of the synthesis parameters becomes an iterative trial-and-error loop. This is where our project comes in, as it relies on the direct in-situ monitoring of the diffusion processes during the synthesis and growth of inorganic functional materials. As the iterative trial-and-error experiments for the synthesis of multicomponent systems are avoided, our study will efficiently save valuable resources and possibly even accelerate the discovery of new materials. To this end, this project pursues two directions: (1) In-situ monitoring of phase formation and grain growth of complex multicomponent materials at elevated temperatures using synchrotron-based techniques; (2) the implementation of a multimodal analytical approach with optimized "machine learning" -based data interpretation. We will focus on functional inorganic materials with strong property relationships, namely intermetallic Heusler alloys and oxide double perovskites, both with high spin polarization. We use these as model systems to study disorder phenomena and the growth of their nanoparticles (NPs) in carbon nanotubes (CNTs). The combination of the expertise between chemistry, physics and materials science provided by the applicants Dr. Ana Guilherme Buzanich (BAM) and Dr. Sabine Wurmehl (IFW) will help make the project a success through diverse scientific perspectives and skills. The project offers two very attractive PhD projects as it combines chemistry at the forefront of synthesis development and high-quality multimodal analysis techniques that will give the two PhD students a broad knowledge of interdisciplinary methodologies. Our results will be available to researchers across physical materials science that can be immediately applied to catalysis, energy-related materials, and other functional materials.