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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Enhanced Structural and Magnetic Coupling in a Mesocrystal-Assisted Nanocomposite
Yuanmin Zhu1, Qian Zhan1, Jan-Chi Yang2
1Department of Material Physics and Chemistry, University of Science and Technology Beijing , Beijing 100083, China.
ACS Applied Materials & Interfaces
|November 18, 2015
Summary
Researchers developed a novel nanocomposite material with enhanced room-temperature magnetic properties. This self-assembled mesocrystal-perovskite system integrates nickel iron oxide and lanthanum calcium manganite for advanced functionalities.
Area of Science:
- Materials Science
- Nanotechnology
- Solid State Physics
Background:
- Nanocomposites offer unique physical properties and functionalities due to advances in synthesis.
- Heteroepitaxial mesocrystal-perovskite nanocomposites represent a promising area for materials innovation.
Purpose of the Study:
- To synthesize and characterize a novel heteroepitaxial mesocrystal-perovskite nanocomposite: (NiFe2O4)0.33:(La0.67Ca0.33MnO3)0.67.
- To investigate the structural evolution and magnetic properties of the synthesized nanocomposite.
- To demonstrate a method for manipulating material properties through self-assembled nanocomposite systems.
Main Methods:
- Advanced materials synthesis techniques.
- Elaborate structural studies (e.g., X-ray diffraction).
- Magnetic measurements.
- X-ray absorption spectroscopy.
Main Results:
- Formation of ordered octahedral mesocrystal arrays of NiFe2O4 nanocrystals with {111} facets.
- Concomitant structural phase transition in the La0.67Ca0.33MnO3 matrix.
- Significant enhancement of magnetic properties at room temperature.
- Evidence of magnetic coupling at heterointerfaces mediated by Mn-O6 and (Ni,Fe)-O6 octahedrons.
Conclusions:
- The postannealing process induces structural evolution and enhances magnetic properties in the mesocrystal-perovskite nanocomposite.
- The integrated functionalities arise from the specific structural arrangement and interfacial magnetic coupling.
- This work presents a viable strategy for designing advanced functional materials by self-assembly.
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