RII Track 4: Understanding Defect Chemistry in Sodium Chalcogenide Superionic Conductors by Advanced Neutron Technology

RII 轨道 4：通过先进中子技术了解硫属化钠超离子导体中的缺陷化学

• 批准号: 2033397
• 负责人: Hui Wang
• 金额: $ 25.25万
• 依托单位: University of Louisville Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-12-15 至 2024-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2033397&HistoricalAwards=false
• 关键词: RII; Track; Understanding; Defect; Chemistry

Solid-state sodium (Na) superionic conductors play a significant role in applications for sensors and solid-state Na batteries. Chalcogenide Na-ion conductors have attracted intense attentions due to high Na+ ionic conductivity and cold-press included densification. For these conductors, the presence of Na defects (i.e. vacancies or interstitials) in their crystal structures strongly influence their ionic conductivities. Thus, it is essential to better understanding on the subtle structural change for the synthesis and doping of chalcogenide Na-ion conductors. One main challenge is the difficulty to accurately catch the subtle defect structure through regular X-ray diffraction technology. This project takes advantages of high resolution of neutrons to access advanced neutron facilities at Oak Ridge National Laboratory (ORNL), where the PI and her collaborators will investigate the crystal structures of Na3SbS4-xSex materials to obtain the fundamental knowledge of defect chemistry in chalcogenide conductors. The findings of this research will promote the development of new solid electrolytes for high performance solid-state Na batteries. In addition, this project will establish a longstanding collaboration between University of Louisville (UofL) and ORNL, which is a bridge to benefit other faculties at Kentucky to foster more collaborative research in boarder materials science fields. Chalcogenide Na superionic conductors (i.e. Na3PCh4 and Na3SbCh4 (Ch=S, Se)) have great potential for applications in solid-state Na batteries. In these conductors, defect chemistry such as Na vacancies significantly affect the ion transport across crystal frameworks. The goal of this proposed research is to use Na3SbS4-xSex conductors as model materials to understand the physical principle underlying the defect changes and reveal how the defect local structures influence the Na+ ion diffusion. Through a collaborative research with neutron scientists in Spallation Neutron Source (SNS) at ORNL, we aim to advance the current state-of-the-art understanding on defect chemistry and their effects on the polymorphs as well as ion transport in chalcogenide Na-ion conductors. This research will involve: (1) Employ in situ neutron diffraction to closely observe phase formation and track the subtle structure changes such as Na defects for Na3SbS4-xSex conductors; (2) Reveal the Se doping effects on the crystal structure (phase stability and Na defect dynamics) as well as the ion diffusion across crystals of Na3SbS4-xSex conductors. The successful demonstration of the proposed work will provide a new fundamental understanding on the synthesis and ion transport in Na3SbS4-xSex chalcogenide conductors. The obtained knowledge will not only pave the way to understand other defects-contained crystalline Na-ion conductors, but also promote the development of new solid electrolytes in solid-state Na batteries for future energy storage.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.

固态钠（NA）超电子导体在传感器和固态NA电池的应用中起着重要作用。由于高Na+离子电导率和冷压包括致密化，因此硫化核化合物Na-ion导体引起了强烈的注意。对于这些导体，其晶体结构中NA缺陷（即空位或间隙）的存在强烈影响其离子电导率。因此，必须更好地理解葡萄干元素Na-Ion导体的合成和掺杂的细微结构变化。一个主要的挑战是难以通过常规的X射线衍射技术准确地捕获细微的缺陷结构。该项目具有高分辨率中子的优势，可以在Oak Ridge国家实验室（ORNL）访问高级中子设施，PI和她的合作者将研究Na3SBS4-XSEX材料的晶体结构，以获取Chalcogenide指挥中缺陷化学的基本知识。这项研究的发现将促进用于高性能固态NA电池的新固体电解质的开发。此外，该项目将在路易斯维尔大学（UOFL）和ORNL之间建立长期的合作，这是使肯塔基州其他学院受益的桥梁，以促进寄宿生材料科学领域的更多协作研究。甲状腺素NA上离子导体（即Na3pCh4和Na3SBCH4（CH = S，SE））具有在固态NA电池中应用的巨大潜力。在这些导体中，缺陷化学（例如NA空位）显着影响跨晶体框架的离子运输。这项拟议的研究的目的是将Na3SBS4-XSEX导体用作模型材料，以了解缺陷变化的物理原理，并揭示缺陷局部结构如何影响Na+离子扩散。通过与ORNL的中子科学家（SNS）中的中子科学家进行的合作研究，我们旨在促进对缺陷化学的最新理解及其对多晶型物的影响以及硫代基因Na-ion导体中的离子运输。这项研究将涉及：（1）采用原位中子衍射来紧密观察相形成并跟踪微妙的结构变化，例如Na3SBS4-XSEX导体的NA缺陷； （2）揭示了对晶体结构（相位稳定性和NA缺陷动力学）以及跨Na3SBS4-XSEX导体晶体的离子扩散的掺杂​​作用。拟议的工作的成功演示将为Na3SBS4-XSEX辣椒剂导体中的合成和离子转运提供新的基本理解。获得的知识不仅将为理解其他具有缺陷的结晶Na-Ion导体铺平道路，而且还可以促进固态NA电池中新的固体电解质的开发，以进行未来的储能。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子功能和广泛影响的评估来评估CRITERIA的评估，这是值得的。

项目成果

Visualization of Solid‐State Synthesis for Chalcogenide Na Superionic Conductors by in‐situ Neutron Diffraction

原位中子衍射可视化硫属化物 Na 超离子导体的固态合成

• DOI: 10.1002/cssc.202101839
• 发表时间: 2021
• 期刊: ChemSusChem
• 影响因子: 8.4
• 作者: Halacoglu, Selim;Chertmanova, Sabina;Chen, Yan;Li, Yang;Rajapakse, Manthila;Sumanasekera, Gamini;Narayanan, Badri;Wang, Hui
• 通讯作者: Wang, Hui