Ionic transport properties of nanocrystalline high entropy oxides

纳米晶高熵氧化物的离子输运特性

• 批准号: 424789449
• 负责人: Professor Dr.-Ing. Horst Hahn, since 2/2022
• 金额: --
• 依托单位: Institut für Nanotechnologie (INT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/424789449?language=en
• 关键词: Ionic; transport; properties; nanocrystalline; entropy

The primary scientific goal of the present proposal is to investigate the ionic transport along both sublattices in two categories of a novel class of material, high entropy oxides (HEO) – Li+ ion transport along the cation sublattice in transition metal based R-HEO with a phase-pure rock salt structure, and oxygen ion transport along the anion sublattice of rare earth based F-HEO having a phase-pure fluorite structure. It is expected that our collaboration on ionic transport properties will make valuable contributions towards understanding the structure and functional properties and assist in exploring the full potential of the new class of oxide materials.The microstructure of the powders and ceramics prepared at the Indian partner institution IIT Madras will be characterized at the Institute of Nanotechnology (INT) at Karlsruhe Institute of Technology (KIT) using XRD, SEM, TEM and EXAFS. Subsequently, the electrochemical properties will be analyzed using Electrochemical Impedance Spectroscopy (EIS), in case of Li+-ionic transport in a temperature range around ambient temperature, in case of O2—ionic transport at elevated temperatures. Based on the fundamental studies of the ionic transport we will assemble and characterize half and full Li-ion battery cells and Solid Oxide Fuel Cells (SOFC) using HEO materials. NMR will be employed in addition to determine Li-ion diffusivity and Raman spectroscopy to detect the defect chemistry in HEO. The work program builds on a 20-year collaboration on nanocrystalline ceramics between the German and the Indian principal investigators (PI) and their pioneering collaborative work in the new field of HEO over the past three years. The strengths of both groups are well incorporated in the proposed joint research effort. At IIT Madras, the research focus of the Indian PI is on synthesis, processing and structure characterization, at the Institute of Nanotechnology (INT) at Karlsruhe Institute of Technology (KIT) the focus is largely complementary and addresses the characterization of the microstructure using advanced techniques and the study of the functional properties that have potential for applications.The preliminary work - supported largely by discretionary funds available at INT and IITM - has already led to some basic understanding of HEO and will be developed further during this proposal in a formal manner. The synergy between the two groups has been clearly established in terms of the number of recent excellent publications, including one in Nature Communications. In terms of innovative ideas in science and evidence for successful collaboration, the proposal addresses directly the theme of the present DST-DFG joint call for Indo-German collaborative research activities in materials science and engineering.

本提案的主要科学目标是研究在两类新型材料中沿着两个亚晶格的离子传输，即沿着具有纯相岩盐结构的基于过渡金属的R-HEO中的阳离子亚晶格的高熵氧化物（HEO）- Li+离子传输，以及沿着具有纯相萤石结构的基于稀土的F-HEO的阴离子亚晶格的氧离子传输。预计我们在离子输运性质方面的合作将为理解结构和功能性质做出宝贵贡献，并有助于探索新型氧化物材料的全部潜力。在印度合作机构IIT Madras制备的粉末和陶瓷的微观结构将在卡尔斯鲁厄理工学院（KIT）的纳米技术研究所（INT）使用XRD进行表征，SEM、TEM和EXAFS。随后，将使用电化学阻抗谱（EIS）分析电化学性质，在Li+离子在环境温度附近的温度范围内传输的情况下，在O2离子在升高的温度下传输的情况下。基于离子传输的基础研究，我们将使用HEO材料组装和表征半和全锂离子电池和固体氧化物燃料电池（SOFC）。此外，还将采用NMR来确定锂离子扩散率，并采用拉曼光谱来检测HEO中的缺陷化学。 该工作计划建立在德国和印度主要研究者（PI）之间在纳米晶体陶瓷方面长达20年的合作以及他们在过去三年中在HEO新领域的开创性合作工作的基础上。两个小组的优势都很好地融入了拟议的联合研究工作中。在IIT Madras，印度PI的研究重点是合成，加工和结构表征，在卡尔斯鲁厄理工学院（KIT）的纳米技术研究所（INT），重点主要是互补性的，并利用先进技术对微观结构进行表征，并研究具有应用潜力的功能特性。主要由INT和IITM提供的自由支配资金支持，已经导致对HEO有了一些基本的了解，并将在本提案期间以正式方式进一步发展。这两个团体之间的协同作用已经在最近的优秀出版物的数量方面得到了明确的确立，其中包括《自然通讯》上的一篇。在科学创新思想和成功合作的证据方面，该提案直接涉及目前DST-DFG联合呼吁印度-德国在材料科学和工程方面合作研究活动的主题。