Theory of energy landscapes and ion transport in amorphous materials

非晶材料中的能量景观和离子传输理论

• 批准号: 452995129
• 负责人: Professor Dr. Philipp Maass
• 金额: --
• 依托单位: Arbeitsgruppe Statistische Physik
• 依托单位国家: 德国
• 项目类别: Research Units
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/452995129?language=en
• 关键词: Theory; energy; landscapes; ion; transport

Ion transport in amorphous materials is of vital interest for many applications. In particular glassy electrolytes can be tailored to specific needs because of a high flexibility in their chemical compositions. They find applications in batteries, smart windows, super-capacitors, optical wave guides, sensors, and others. This research project aims at developing theoretical methods to construct energy landscapes for the ionic motion in glassy materials and to predict ionic transport properties such as conductivities and their activation energies based on this landscape construction. For the landscape construction, chemical and structural information about mutually linked units is used that are forming the host network for the ionic motion. The reliability of the theoretical developments will be checked against experimental observations. These are, in particular, diffusion profiles obtained from a novel technique of charge attachment induced ion transport, correlation functions and spectral densities measured by nuclear magnetic resonance (NMR), as well as results for local compositions and structural configurations obtained from magic angle spinning NMR and atom probe tomography. Specific objectives are the modelling of concentrations of chemical units building the glassy network, of spatial charge distributions derived from these concentrations, and calculations of ionic transport quantities by means of kinetic Monte Carlo and molecular dynamics simulations. The simulations are complemented by analytical calculations based on percolation and effective medium theories. This includes analyses on how the ion dynamics are affected by the Coulomb interaction between mobile ions and by the concentration of empty ion sites in a glass.

离子在非晶材料中的输运在许多应用中具有重要意义。特别是玻璃电解质，由于其化学成分的高度灵活性，可以根据特定需要进行定制。它们在电池、智能窗户、超级电容器、光波导、传感器等领域都有应用。本研究项目旨在发展构建玻璃材料中离子运动能量景观的理论方法，并在此景观构建的基础上预测离子传输特性，如电导率及其活化能。在景观建设中，相互连接的单元的化学和结构信息被用于形成离子运动的宿主网络。理论发展的可靠性将由实验观察来检验。特别是，通过电荷附着诱导离子输运的新技术获得的扩散曲线，通过核磁共振（NMR）测量的相关函数和谱密度，以及通过魔角自旋核磁共振和原子探针断层扫描获得的局部成分和结构构型的结果。具体目标是建立玻璃网络的化学单元的浓度模型，由这些浓度推导的空间电荷分布，以及通过动力学蒙特卡罗和分子动力学模拟计算离子输运量。模拟得到了基于渗流理论和有效介质理论的解析计算的补充。这包括分析离子动力学如何受到移动离子之间的库仑相互作用和玻璃中空离子位置的浓度的影响。