Unknown

Dataset Information

0

Defect Chemistry, Sodium Diffusion and Doping Behaviour in NaFeO2 Polymorphs as Cathode Materials for Na-Ion Batteries: A Computational Study.

ABSTRACT: Minor metal-free sodium iron dioxide, NaFeO2, is a promising cathode material in sodium-ion batteries. Computational simulations based on the classical potentials were used to study the defects, sodium diffusion paths and cation doping behaviour in the ?- and ?-NaFeO2 polymorphs. The present simulations show good reproduction of both ?- and ?-NaFeO2. The most thermodynamically favourable defect is Na Frenkel, whereas the second most favourable defect is the cation antisite, in which Na and Fe exchange their positions. The migration energies suggest that there is a very small difference in intrinsic Na mobility between the two polymorphs but their migration paths are completely different. A variety of aliovalent and isovalent dopants were examined. Subvalent doping by Co and Zn on the Fe site is calculated to be energetically favourable in ?- and ?-NaFeO2, respectively, suggesting the interstitial Na concentration can be increased by using this defect engineering strategy. Conversely, doping by Ge on Fe in ?-NaFeO2 and Si (or Ge) on Fe in ?-NaFeO2 is energetically favourable to introduce a high concentration of Na vacancies that act as vehicles for the vacancy-assisted Na diffusion in NaFeO2. Electronic structure calculations by using density functional theory (DFT) reveal that favourable dopants lead to a reduction in the band gap.

SUBMITTER: Kuganathan N 

PROVIDER: S-EPMC6803870 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

Json Xml
altmetric image

Publications

Defect Chemistry, Sodium Diffusion and Doping Behaviour in NaFeO<sub>2</sub> Polymorphs as Cathode Materials for Na-Ion Batteries: A Computational Study.

Kuganathan Navaratnarajah N   Kelaidis Nikolaos N   Chroneos Alexander A  

Materials (Basel, Switzerland) 20191004 19

Minor metal-free sodium iron dioxide, NaFeO<sub>2</sub>, is a promising cathode material in sodium-ion batteries. Computational simulations based on the classical potentials were used to study the defects, sodium diffusion paths and cation doping behaviour in the α- and β-NaFeO<sub>2</sub> polymorphs. The present simulations show good reproduction of both α- and β-NaFeO<sub>2</sub>. The most thermodynamically favourable defect is Na Frenkel, whereas the second most favourable defect is the catio  ...[more]

Similar Datasets

Unknown Defect Chemistry and Na-Ion Diffusion in Na3Fe2(PO4)3 Cathode Material.
| S-EPMC6515689 | biostudies-other
Unknown Twin boundary defect engineering improves lithium-ion diffusion for fast-charging spinel cathode materials.
| S-EPMC8149699 | biostudies-literature
Unknown Surface enrichment and diffusion enabling gradient-doping and coating of Ni-rich cathode toward Li-ion batteries.
| S-EPMC8316340 | biostudies-literature
Unknown Synthesis and Electrochemical Properties of LiNi0.5Mn1.5O4 Cathode Materials with Cr3+ and F- Composite Doping for Lithium-Ion Batteries.
| S-EPMC5472648 | biostudies-literature
Unknown Building High Power Density of Sodium-Ion Batteries: Importance of Multidimensional Diffusion Pathways in Cathode Materials.
| S-EPMC7058792 | biostudies-literature
Unknown Recent Developments of Cathode Materials for Thermal Batteries.
| S-EPMC8882827 | biostudies-literature
Unknown Dynamic behaviour of interphases and its implication on high-energy-density cathode materials in lithium-ion batteries.
| S-EPMC5414066 | biostudies-literature
Unknown An Efficient Evaluation of F-doped Polyanion Cathode Materials with Long Cycle Life for Na-Ion Batteries Applications.
| S-EPMC5665866 | biostudies-literature
Unknown Facilitating Lithium-Ion Diffusion in Layered Cathode Materials by Introducing Li+/Ni2+ Antisite Defects for High-Rate Li-Ion Batteries.
| S-EPMC6946265 | biostudies-literature
Unknown Optimization of Layered Cathode Materials for Lithium-Ion Batteries.
| S-EPMC5456936 | biostudies-other