CAS-Climate: Identifying and Characterizing the Structures and Physical Properties of Sodiated Intermetallics

摘要锂离子可充电电池已经融入到我们的日常生活中，并在各种交通方式中发挥着重要作用。将新能源存储技术扩展到新兴应用领域的需求越来越大，例如太阳能电池或风车等设备产生的能源的电池。然而，没有一种完美的电池适用于所有的应用！在材料研究部固态与材料化学项目的支持下，科罗拉多州立大学的艾米·普列托博士和她的学生们专注于开发更好的钠离子电池材料，因为钠比锂更丰富。该项目的另一个关键方面是学生在电化学和储能研究方面的培训。这解决了美国对这一领域训练有素的劳动力的迫切需求。技术摘要：钠离子电池研究的一种常见方法是简单地筛选锂离子电池技术中用于钠离子系统的最佳候选材料。通常，这种策略从根本上是有缺陷的，因为李娜和李娜表现出惊人的不同化学反应。用于钠离子电池的阴极和阳极的化学发展不如锂离子电池的化学发展或理解得好，并且一些用于存储锂的最佳阳极材料不存储Na。因此，合金阳极材料，包括锑基（sb基）合金，由于其相对较高的重量和体积容量以及在类似Na/Na+的电位下工作的能力而引起了极大的兴趣，从而产生了高的总能量密度。然而，在Na插入Sb过程中产生的结构似乎不遵循基于相图的热力学预测的中间体，而是经常通过非晶中间体进行。在材料研究部固态和材料化学项目的支持下，科罗拉多州立大学的Amy Prieto博士和她的学生研究了这些插入过程和通过电化学介导/解氧金属锑化物（MSb）形成的NaxSby化合物，它呈现出一种非常丰富的成分和结构景观，尚未从根本上理解。他们开发并测试了表征技术工具箱来研究这些相，并将这些发现应用于其他合金基电极。他们的研究工作是基于这样一个假设：如果人们能够识别和表征在这些阳极被固化和去离子化时进入的中间固态结构，那么对该系统的热力学和动力学的深刻理解以及用于清洁能源应用的新材料将会出现。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 AbstractLithium-ion rechargeable batteries have been integrated into our everyday lives in mobile electronics, and are being incorporated in a significant way in various modes of transportation. There is increasing demand to extend new energy storage technologies toward emerging applications such as batteries for the energy produced by devices like solar cells or windmills. However, there is no one perfect battery for every application! With the support of the Solid State and Materials Chemistry Program in the Division of Materials Research, Dr. Amy Prieto of Colorado State University and her students are focused on developing better materials for sodium ion batteries, because sodium is much more naturally abundant than lithium. Another key aspect of this project is the training that students receive in electrochemistry and energy storage research. This addresses the desperate need in the United States for a workforce trained in this field. Technical AbstractA common approach to Na-ion battery research is to simply screen the top candidates from Li-ion battery technologies for use in Na-ion systems. Often, this strategy is fundamentally flawed as Li and Na exhibit surprisingly different chemistries. The chemistries developed for cathodes and anodes for Na-ion batteries are not nearly as well developed or understood as those of Li, and some of the best anode materials for storing Li do not store Na. As a result, alloying anode materials, including antimony-based (Sb-based) alloys, have been of great interest due to their relatively high gravimetric and volumetric capacities and their ability to operate at potentials similar to Na/Na+, resulting in high overall energy densities. However, the structures produced during Na insertion into Sb do not appear to follow the thermodynamically predicted intermediates based on phase diagrams, and instead often proceed via amorphous intermediates. With the support of the Solid State and Materials Chemistry Program in the Division of Materials Research, Dr. Amy Prieto of Colorado State University and her students study these insertion processes and the NaxSby compounds formed by electrochemically sodiating/desodiating metal antimonides (MSb), which present a very rich compositional and structural landscape that is yet to be fundamentally understood. They develop and test a toolbox of characterization techniques to study these phases and apply these findings to other alloy-based electrodes. Underlying their research efforts is the hypothesis that if one can identify and characterize the intermediate solid-state structures that are accessed as these anodes are sodiated and desodiated, a deep understanding of the thermodynamics and kinetics of this system along with new materials for clean energy applications will emerge.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.