Electrical properties of the high entropy oxide(Mg,Co,Ni,Zn)1-xLixO (x=0,3)

• Grant number: 23/02263-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2023
• End date: April 30, 2024
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Lilian Menezes de Jesus
• Grantee: Gregório Sant'Anna
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

High entropy oxides constitute a new class of materials, in which it is possible to obtain a solid solution that is not predicted in the phase diagram of the constituent elements. The sharing of the same crystal structure site by more than four cations generates a high configuration entropy, which may be able to stabilize the solid solution. Furthermore, interactions among the various cations can lead to new and unexpected properties. Thus, these materials are of both technological and scientific interest, since the physical mechanisms by which the properties are manifested are still unclear. In this project, we propose to investigate the electrical properties of ceramics from the system (Mg,Co,Ni,Zn)1-xLixO (x=0.3). This high-entropy oxide was first synthesized in 2020, in a work that demonstrated its potential as an active material in lithium-ion battery electrodes. However, there are still no reports that investigate the electrical properties of this material in the form of ceramic bodies. Impedance spectroscopy at a wide range of frequencies and temperatures will be applied to evaluate charge conduction processes, determining whether electrical conduction takes place mainly via electronic or ionic carriers or whether conduction is mixed. In addition, appropriate correlations will be made between the electrical response and the microstructure of the produced materials. The study of the electrical properties of ceramics at the microstructural level, which is proposed here, is of fundamental importance in order to advance the understanding of the phenomenology behind such properties and, consequently, in the application of (Mg,Co,Ni,Zn)1-xLixO in devices electronics, especially energy storage, such as lithium-ion batteries.