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Updated: Sep 10, 2025
09:41
Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
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Descriptors for Predicting Single- and Multi-Phase Formation in High-Entropy Oxides: A Unified Framework Approach
Alejandro F Manchón-Gordón1, Paula Panadero-Medianero2, Javier S Blázquez2
1Instituto de Ciencia de Materiales de Sevilla, CSIC-Universidad de Sevilla, C. Américo Vespucio 49, 41092 Sevilla, Spain.
Materials (Basel, Switzerland)
|August 28, 2025
Summary
This study introduces a new framework to predict the phase stability of high-entropy oxides (HEOs). The approach combines key parameters to identify compositional ranges favoring single-phase HEO formation.
Area of Science:
- Materials Science
- Solid State Chemistry
- Ceramic Engineering
Background:
- High-entropy oxides (HEOs) are advanced ceramic materials with complex compositions.
- Predicting the single-phase crystal structure and stability of HEOs is challenging due to their extensive compositional flexibility.
- Current methods struggle to accurately forecast HEO properties and phase formation.
Purpose of the Study:
- To examine key parameters used for predicting HEO stabilization.
- To introduce a unified framework for analyzing HEO phase stability.
- To identify compositional ranges favoring single-phase and multi-phase HEO formation.
Main Methods:
- Analysis of normalized configurational entropy per mole of atoms.
- Inclusion of relative cation volume into mean atomic size deviation.
- Development of a predictive model for HEO phase formation.
Main Results:
- A unified framework for HEO stability analysis is proposed.
- The approach combines entropy and size deviation parameters.
- Predictive capability for rock salt, spinel, fluorite, pyrochlore, and perovskite structures is demonstrated.
Conclusions:
- The developed framework offers a first-approximation method for identifying HEO compositional ranges.
- This approach aids in understanding and designing single-phase HEOs.
- Facilitates the prediction of specific HEO crystal structures based on composition.
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