Strongly correlated perovskite lithium ion shuttles

Area of Science:

• Materials Science
• Solid-State Chemistry
• Condensed Matter Physics

Background:

• Solid-state ion shuttles are critical for electrochemical devices, memory, and neuromorphic computing.
• Conventional doping methods for ionic conductivity face limitations in dopant concentration and ionic conductivity.

Purpose of the Study:

• To demonstrate perovskite nickelates as efficient Li-ion shuttles.
• To suppress electronic transport via Mott transition in these materials.
• To explore a new design strategy for ion conductors.

Main Methods:

• Electrochemical lithiation of samarium nickelate (SmNiO3) to create Li-SNO.
• Investigating interstitial Li+ ion sites and lattice expansion.
• Generalizing the approach to other rare-earth perovskite nickelates and Na+ dopants.

Main Results:

• Achieved high mobile Li+ concentration in interstitial sites of Li-SNO.
• Observed significant lattice expansion facilitating fast Li+ conduction.
• Demonstrated reduced activation energy for ion transport.
• Showcased potential of other rare-earth nickelates and Na+ as dopants.

Conclusions:

• Perovskite nickelates are promising Li-ion shuttles with suppressed electronic transport.
• Interstitial doping in quantum materials offers a new avenue for designing advanced ion conductors.
• This approach highlights the potential of emergent physics in materials design for electrochemical applications.