Related Experiment Video
Updated: Jun 25, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Melting of the Na layers in solid Na0.8CoO2.
M Weller1, A Sacchetti, H R Ott
1Laboratorium für Festkörperphysik, ETH Zürich, 8093 Zürich, Switzerland. weller@phys.ethz.ch
Sodium ion mobility in Na0.8CoO2 increases significantly above 200 K. At 291 K, sodium layers transition to a 2D liquid state, similar to superionic conductors.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Condensed Matter Physics
Background:
- Sodium cobalt oxides (Na x CoO 2 ) are studied for energy storage applications.
- Understanding ion dynamics is crucial for optimizing material performance.
Purpose of the Study:
- To investigate the temperature-dependent behavior of sodium ions in Na 0.8 CoO 2.
- To determine the phase transition of sodium layers.
Main Methods:
- Utilizing 23Na Nuclear Magnetic Resonance (NMR) spectroscopy.
- Performing relaxation measurements to probe ion mobility.
Main Results:
- A rapid increase in sodium ion mobility and diffusion observed above 200 K.
- Evidence for a first-order phase transition at 291 K.
- Sodium layers in Na 0.8 CoO 2 adopt a 2D liquid state above 291 K.
Conclusions:
- The study reveals a transition to a 2D liquid state for sodium ions in Na 0.8 CoO 2 at elevated temperatures.
- This behavior is comparable to that seen in superionic conductors.
- Findings provide insights into ion transport mechanisms in layered materials.
More Related Videos
08:40Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production
Published on: December 6, 2021
08:13Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area
Published on: February 19, 2018
Related Concept Videos
Phase Transitions: Melting and Freezing
Network Covalent Solids
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
Molecular and Ionic Solids
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
Phase Transitions: Sublimation and Deposition
Phase Transitions: Vaporization and Condensation
The Equilibrium Constant