EAPSI: Study of Defect Water-Interactions in Lithium Silicate Ceramics

硅酸锂陶瓷是能源领域固态电池和聚变反应堆的重要组成部分。硅酸锂陶瓷在其晶体结构中含有许多缺陷，这些缺陷会影响系统与水的相互作用，尽管这种关系的确切性质尚不清楚。评估硅酸锂陶瓷中缺陷与水相互作用的机制，将有助于开发电池和聚变反应堆中更持久的材料。基于硅酸锂陶瓷的复杂结构，将采用计算方法提供结构及其随时间演变的广泛的原子水平信息。拟议的研究将与成都中国电子科技大学的祖晓涛博士合作进行。祖博士是计算方法方面的专家，该方法将用于研究硅酸锂陶瓷中的缺陷-水相互作用。第一性原理模拟方法将应用于硅酸锂的模拟，以提供关于晶体结构的广泛的原子和电子信息，包括点和电子缺陷对体积和电子特性的影响，以及在存在水的情况下。确定缺陷区域水扩散变化的机制将有助于深入了解水在硅酸锂陶瓷中发生的任何结构变化中的作用。所提出的工作将提供关于硅酸锂陶瓷的基础知识，然后可以扩展到更复杂的晶体多组分硅酸盐的缺陷结构的研究，包括锂电池中使用的主要材料。该奖项由美国国家科学基金会EAPSI与中国科技部合作资助，支持一名美国研究生的研究。

Lithium silicate ceramics are a critical component of solid state batteries and fusion reactors in the energy sector. Lithium silicate ceramics contain a number of defects in their crystal structure, which can affect how the system interacts with water, though the precise nature of the relationship is unknown. Evaluation of the mechanism by which the defects in the lithium silicate ceramics interact with water will allow for the development of longer lasting materials in batteries and fusion reactors. Based on the complex structure of the lithium silicate ceramic computational methods will be employed to provide extensive atomic level information of the structures and how they evolve with time. The proposed research will be conducted in collaboration with Dr. Xiaotao Zu at the University of Electronic Science and Technology of China in Chengdu. Dr. Zu is an expert in the computational methods which will be employed to study the defect-water interactions in lithium silicate ceramics. First principles simulation methods will be applied to the simulation of lithium silicates to provide extensive atomistic and electronic information about the crystalline structures, including the effects of point and electronic defects on both bulk and electronic properties and in the presence of water. The identification of the mechanisms responsible for the changes in water diffusion in the region of the defects will provide insight into the role of water on any structural changes which occur in lithium silicate ceramics. The proposed work will provide a base of knowledge on lithium silicate ceramics that can then be extended to the investigation of defect structures in more complex crystalline multicomponent silicates, including the primary materials used in lithium batteries. This NSF EAPSI award supports the research of a U.S. graduate student and is funded in collaboration with the Chinese Ministry of Science and Technology.