Magnetically self-assembled SrFe12O19/Fe-Co core/shell particles

Journal Article · Sun Feb 15 04:00:00 EST 2015 · Materials Chemistry and Physics

DOI:https://doi.org/10.1016/j.matchemphys.2014.11.061· OSTI ID:1211082

Xu, X; Park, J; Hong, YK; Lane, AM

Epitaxial growth to synthesize core/shell-structured materials is limited because large lattice mismatches are common between materials. Magnetically hard/soft, core/shell-structured materials can be potentially used for rare-earth free permanent magnets, but their synthesis presents a challenge. We report a wet chemistry method to synthesize core/shell structured particles consisting of a magnetically hard SrFe12O19 core and a soft Fe-Co shell, with a lattice mismatch of similar to 100%, which cannot be achieved by conventional epitaxial growth or other alternative methods. When decreasing the size of the magnetically soft Fe-Co nanoclusters to below 5 nm, we show that they can be magnetically attracted by the hard SrFe12O19 to form core/shell structured particles. An AC demagnetization experiment demonstrates the formation mechanism of the core/shell particles, and their magnetic hysteresis loop shows potential for use as rare-earth free permanent magnets. Published by Elsevier B.V.

• Sponsoring Organization: USDOE Advanced Research Projects Agency - Energy (ARPA-E)
• DOE Contract Number: AR0000189
• OSTI ID: 1211082
• Journal Information: Materials Chemistry and Physics, Journal Name: Materials Chemistry and Physics Vol. 152; ISSN 0254-0584
• Country of Publication: United States
• Language: English