Defect Chemistry and Na-Ion Diffusion in Na3Fe2(PO4)3 Cathode Material.

ABSTRACT: In this work, we employ computational modeling techniques to study the defect chemistry, Na ion diffusion paths, and dopant properties in sodium iron phosphate [Na3Fe2(PO4)3] cathode material. The lowest intrinsic defect energy process (0.45 eV/defect) is calculated to be the Na Frenkel, which ensures the formation of Na vacancies required for the vacancy-assisted Na ion diffusion. A small percentage of Na-Fe anti-site defects would be expected in Na3Fe2(PO4)3 at high temperatures. Long-range diffusion of Na is found to be low and its activation energy is calculated to be 0.45 eV. Isovalent dopants Sc, La, Gd, and Y on the Fe site are exoergic, meaning that they can be substituted experimentally and should be examined further. The formation of Na vacancies and Na interstitials in this mate

SUBMITTER: Kuganathan N 

PROVIDER: S-EPMC6515689 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature