A high-entropy manganite in an ordered nanocomposite for long-term application in solid oxide cells

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Nano-engineered composite oxides offer potential for advanced functional materials.
• Lanthanum strontium manganite and doped ceria are key components in high-temperature energy conversion devices.

Purpose of the Study:

• To realize vertically aligned nanocomposites of lanthanum strontium manganite and doped ceria.
• To assess local structural and electrochemical functionalities and observe oxygen diffusion pathways.
• To investigate the role of nano-engineering in functional oxides.

Main Methods:

• Atom-probe tomography combined with oxygen isotopic exchange.
• Complementary state-of-the-art analytical techniques.
• Density functional theory calculations.

Main Results:

• Vertically aligned nanocomposites with an ordered mesostructure were successfully fabricated.
• High electrochemical activity and suppressed dopant segregation were observed.
• Direct observation of fast oxygen diffusion pathways was achieved.
• Spontaneous cationic intermixing was identified as a mechanism for lattice stabilization.

Conclusions:

• Nano-engineering of functional oxides requires understanding local disorder and long-range arrangements.
• The developed nanocomposites are suitable for high-temperature energy conversion devices.
• An advanced method for analyzing mass transport phenomena in functional oxides was introduced.