Molecular dynamics simulation study of the effect of Ce4+ incorporation at Zr site on the threshold displacement energy in Y4Zr3O12 material

Abstract

ABSTRACT This study utilizes classical molecular dynamics (MD) simulations to examine the structure and the impact of cerium (Ce4+) incorporation, serving as a surrogate for plutonium (Pu), at the zirconium (Zr4+) site on the threshold displacement energy (Ed) for each atom within the δ-phase Y4Zr3O12 material along 100 different directions. The minimum Ed values obtained for Y, Zr, and O in Y4Zr3O12 are 50 eV, 60 eV, and 25 eV, respectively. Notably, the Y cation is more prone to displacement than the Zr cations, while oxygen anions are even more easily displaced than cations, requiring less energy for displacement. Furthermore, the incorporation of Ce4+ at the Zr4+ site in the Y4Zr3-3xCe3xO12 (0 ≤ x ≤ 0.5) system reduces both the minimum and average Ed values for Zr atoms. The presence of Ce also decreases the minimum Ed for Y at x = 0.5 and for OI at x = 0.125, while increasing the minimum Ed for OII at x = 0.25. These findings suggest that the incorporation of Ce can influence the radiation resistance of the Y4Zr3O12 material, thereby offering insights into potential strategies for enhancing its performance under radiation conditions.