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Updated: Jan 9, 2026
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Assessment of Boron Doped Diamond Electrode Quality and Application to In Situ Modification of Local pH by Water Electrolysis
Published on: January 6, 2016
15.3K
Fast Oxide Ion Conduction in Ba3MoNbO8.5 Enhanced by Acceptor Substitution and Dehydration
Lulu Jiang1, Kazuaki Toyoura2, Amir Masoud Dayaghi3
1College of Energy, Soochow University, No 1 Shizi Street, Gusu District, Suzhou 215006, China.
Journal of the American Chemical Society
|December 3, 2025
Summary
Barium Molybdate Niobate (BMN) shows high oxide ion conductivity due to disordered oxygen sites. Doping enhances conductivity and reduces humidity effects, suggesting potential for advanced solid oxide fuel cells.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Electrochemistry
Background:
- Barium Molybdate Niobate (Ba3MoNbO8.5, BMN) is a promising oxide ion conductor.
- Its high conductivity is attributed to disordered oxygen ions on O2 and O3 sites.
- Understanding defect chemistry and transport mechanisms is crucial for optimizing performance.
Purpose of the Study:
- To develop a novel model for defects and transport in BMN.
- To rationalize the effects of hydration and doping on oxide ion conductivity.
- To investigate strategies for enhancing BMN stability and performance.
Main Methods:
- Experimental characterization (conductivity measurements, etc.).
- Computational modeling (density functional theory).
- Analysis of hydration and acceptor substitution effects.
Main Results:
- Hydration increases activation energy and blocks ion transport pathways.
- Acceptor substitution (e.g., Yttrium) improves conductivity and humidity resistance.
- 5 at % Y substitution yields conductivity > 10 mS·cm-1 at 650 °C.
- Grain boundary resistance is influenced by proton and vacancy accumulation.
Conclusions:
- A defect and transport model explains BMN behavior under hydration and doping.
- Acceptor doping is effective in stabilizing BMN against humidity.
- Doping and grain boundary engineering are key for practical applications of BMN-based conductors.
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