CAREER: Multi-dimensional synthetic approach toward alkali-transition metal intermetallics guided by theory and in-situ studies

非技术摘要：材料合成和发现使当前的技术进步成为可能，如锂离子电池、太阳能电池、智能手机、微处理器、医学成像和利用风能的涡轮机。尽管在材料合成方面取得了重大进展，但仍有许多化合物无法通过标准合成路线获得。例如，合成含有延性和软碱金属以及粉状非金属的化合物是具有挑战性的。研究人员遇到了反应物混合的问题，类似于混合巧克力片和曲奇饼。在材料研究部固态和材料化学项目的支持下，这位首席研究员和她的研究小组利用创新的盐类起始材料开发了独特的合成途径。在实时反应监测和理论预测的指导下进行了合成。这种方法产生了独特的碱金属化合物，具有潜在的有用的能量转换和存储性能。此外，作为教育方面，PI促进向公众传播科学成果，促进本科生参与研究，并通过视频教程帮助研究生寻找工作。这些短小的教育和娱乐视频是作为新的ICON计划(爱荷华州化学外展网络)的一部分而创建的。技术总结：这个职业奖项项目由材料研究部的固态和材料化学计划支持，通过针对元素的反应活性明显不同的三元体系，如高活性和挥发性碱金属A、难熔和缓慢的过渡金属M和P-块元素E，将理论-实验协同合成方法推向高度复杂的水平。到目前为止，此类体系的相空间基本上仍未被探索。与类似的R-M-E三元体系(R=稀土金属)形成鲜明对比。从合成的角度来看，元素碱金属是具有挑战性的前体。由于金属/类金属反应物的延展性、挥发性和反应性，涉及碱金属的金属/类金属反应物很难均匀混合，而传统的高温处理，如电弧熔化，则不适用。这一综合实验方法以盐状可混合碱金属氢化物为前驱体，结合变温X射线衍射法的原位反应监测和结构稳定性的理论预测。研究目标包括定向和可控地制备新的三元化合物，这是标准固态化学路线无法实现的，为通过设计实现固相合成铺平了道路。这项研究项目为固体和材料化学领域的基础知识做出了贡献，符合NSF-DMR计划的任务。此外，作为教育方面，PI促进向公众传播科学成果，促进本科生参与研究，并通过视频教程帮助研究生寻找工作。这些短小的教育而又有趣的视频是作为新的ICON计划(爱荷华州化学外展网络)的一部分而创建的。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical summary:Material synthesis and discovery has enabled current technological advances, such as lithium-ion batteries, solar cells, smartphones, microprocessors, medical imaging, and turbines for harnessing wind energy. Despite significant progress in material synthesis, there are many compounds that remain inaccessible by standard synthetic routes. For instance, synthesis of compounds containing ductile and soft alkali metals and powdery non-metals is challenging. Researchers encounter issues with reactants mixing, similar to mixing chocolate chips and cookie dough. With this CAREER award project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, the principle investigator and her research group develop unique synthetic pathways by utilizing innovative salt-like starting materials. The synthesis is guided by real-time reaction monitoring and theoretical predictions. This approach yields unique alkali metal compounds with potentially useful properties for energy conversion and storage. Additionally, as an education aspect, the PI promotes dissemination of scientific results to the general public, facilitates involvement of undergraduate students into research, and assists graduate students with their job search through video tutorials. These short educational, yet entertaining videos are created as part of the new ICON program (Iowa Chemistry Outreach Network).Technical summary: This CAREER award project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, advances a synergistic theoretical-experimental synthetic approach to a high level of complexity by aiming at ternary systems with distinctly dissimilar reactivities of elements, such as highly reactive and volatile alkali metals A, refractory and kinetically sluggish transition metals M, and p-block element E. Until now the phase spaces of such systems have remained essentially unexplored, in a stark contrast with similar R-M-E ternary systems (R = rare-earth metal). From the synthetic point of view, elemental alkali metals are challenging precursors. Because of their ductility, volatility, and reactivity, homogeneous mixing of metal/metalloid reactants involving an alkali metal is difficult, while traditional high-temperature treatments, such as arc-melting, are not applicable. This comprehensive experimental approach utilizes salt-like mixable alkali metal hydrides as precursors and is coupled with in-situ reaction monitoring by variable temperature X-ray diffraction and theoretical predictions of structure stability. The research objectives include the targeted and controlled preparation of new ternary compounds, which are unavailable by standard solid state chemistry routes, paving a way to solid state synthesis by design. This research project contributes to the basic knowledge in the field of solid state and materials chemistry, in line with the NSF-DMR program mission. Additionally, as an education aspect, the PI promotes dissemination of scientific results to the general public, facilitates involvement of undergraduate students into research, and assists graduate students in their job search through video tutorials. These short educational, yet entertaining videos are created as part of the new ICON program (Iowa Chemistry Outreach Network).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.