Related Experiment Video
Updated: Jul 16, 2025
08:43
Molten-Salt Synthesis of Complex Metal Oxide Nanoparticles
Published on: October 27, 2018
18.1K
(Mg,Mn,Fe,Co,Ni)O: A rocksalt high-entropy oxide containing divalent Mn and Fe
Yuguang Pu1, Duncan Moseley2, Zhen He3
1Department of Chemical and Materials Engineering, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
Science Advances
|September 20, 2023
Summary
Synthesizing manganese- and iron-containing high-entropy oxides (HEOs) is challenging. This study developed a novel method to create a stable rocksalt FeO-HEO with unique magnetic properties.
Area of Science:
- Materials Science
- Solid State Chemistry
- Nanotechnology
Background:
- High-entropy oxides (HEOs) present fundamental questions regarding structure, stability, and property relationships.
- Incorporating Fe(II) and Mn(II) into rocksalt HEOs is theoretically challenging due to predicted instability.
Purpose of the Study:
- To develop a bottom-up synthesis method for Mn- and Fe-containing rocksalt HEOs.
- To investigate the structural, chemical, and magnetic properties of the synthesized FeO-HEO.
- To explore the phase stability of Mn- and Fe-containing HEOs.
Main Methods:
- Bottom-up synthesis of rocksalt FeO-HEO.
- Comprehensive crystallographic analysis.
- Valence and spin state determination of iron species.
- Magnetic characterization (antiferromagnetic ordering).
Main Results:
- Successful synthesis of Mn- and Fe-containing rocksalt HEO (FeO-HEO).
- Demonstrated improved structural robustness and random cation-site occupancy.
- Identified valence and spin states of iron and observed antiferromagnetic order below ~218 K.
- Predicted phase stability conditions for related HEOs.
Conclusions:
- The developed method enables the synthesis of stable FeO-HEOs.
- The oxygen sublattice acts as a viable buffer layer.
- This work offers insights into designing and tailoring properties of novel HEOs.
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