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Published on: March 27, 2018
Synthesis, structure and ionic conductivity in nanopolycrystalline BaF2/CaF2 heterolayers
Dean C Sayle1, James A Doig, Stephen C Parker
1Dept. Environmental and Ordnance Systems, Cranfield University, RMCS, Shrivenham, Swindon, UK. sayle@rmcs.cranfield.ac.uk
Chemical Communications (Cambridge, England)
|August 23, 2003
Summary
Atomistic simulations reveal that nano-polycrystalline Barium Fluoride/Calcium Fluoride heterolayers exhibit significantly enhanced ionic conductivity. Grain-boundary diffusion is identified as the primary mechanism responsible for this improved performance in these advanced materials.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Computational Materials Science
Background:
- Ionic conductivity in solid materials is crucial for energy applications.
- Nanostructured materials offer unique properties compared to bulk counterparts.
- Barium Fluoride (BaF2) and Calcium Fluoride (CaF2) are known ionic conductors.
Purpose of the Study:
- To investigate the ionic conductivity of nano-polycrystalline BaF2/CaF2 heterolayers.
- To compare the conductivity of these heterolayers with their bulk components.
- To elucidate the underlying mechanisms governing ionic transport in these nanostructures.
Main Methods:
- Atomistic simulations were employed to model the heterolayer structures.
- Calculations focused on determining ionic conductivity.
- Analysis of diffusion pathways at grain boundaries was performed.
Main Results:
- The calculated ionic conductivity of nano-polycrystalline BaF2/CaF2 heterolayers is significantly higher than that of bulk BaF2 and CaF2.
- Simulations indicate that grain boundaries play a critical role in enhancing ionic transport.
- Specific diffusion pathways at the interfaces were identified.
Conclusions:
- Nano-polycrystalline BaF2/CaF2 heterolayers demonstrate superior ionic conductivity.
- Grain-boundary diffusion is the dominant mechanism for fast ionic conduction in these systems.
- These findings suggest potential for advanced ionic conductor applications.
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