Radiation Damage Mechanisms in Oxide-Based Solid Electrolytes.

Area of Science:

• Materials Science
• Solid-State Battery Technology
• Computational Materials Science

Background:

• Ion implantation is explored to enhance solid-state battery performance by mitigating dendrite formation on oxide electrolytes.
• Understanding the atomistic mechanisms and side effects of ion implantation on materials like Li$_{7}$La$_{3}$Zr$_{2}$O$_{12}$ (LLZO) is crucial but poorly understood.

Purpose of the Study:

• To elucidate the atomistic mechanisms of radiation-induced damage in LLZO using molecular dynamics simulations.
• To investigate how ion implantation affects the structural and conductive properties of LLZO surfaces.

Main Methods:

• Molecular dynamics (MD) simulations were employed to model the effects of heavy ion impacts on the LLZO crystal structure.
• Analysis focused on the evolution of defects, lattice connectivity, and potential changes in ionic pathways.

Main Results:

• Radiation damage in LLZO is driven by heavy ion recoils, forming antisite defect clusters.
• Defect cluster density decreases with increasing recoil energy, indicating complex cascade fragmentation.
• Low-energy cascades disrupt Li-ion transport pathways by affecting the La-O network.
• High-energy cascades can create new Li-ion conduction pathways through enhanced Zr-O network connectivity.

Conclusions:

• Ion implantation strategies require careful optimization to balance surface modification for dendrite resistance with the preservation of ionic conductivity.
• The study provides a mechanistic understanding of radiation damage in LLZO, informing future battery electrolyte design and treatment protocols.