Absorption Band Tunable La-Sr Co-Doped BaCo2-W Type Hexaferrites
Juan Li1,2, Xuetao Sun1,2
1College of Materials Science and Engineering, Zhejiang University of Technology, Hangzhou 310014, China.
Materials (Basel, Switzerland)
|September 9, 2023
Summary
La-Sr co-doped barium hexaferrites show tunable microwave absorption properties. Optimized doping enhances electromagnetic wave dissipation, making them promising for radar absorption applications.
Area of Science:
- Materials Science
- Solid State Chemistry
- Electromagnetics
Background:
- Hexaferrites are advanced magnetic materials with potential applications in microwave absorption.
- Tuning the composition of hexaferrites is crucial for optimizing their electromagnetic properties.
Purpose of the Study:
- To investigate the effect of La-Sr co-doping on the structural and electromagnetic properties of BaCo2Fe16O27 hexaferrites.
- To evaluate the microwave absorbing performance of these co-doped materials.
Main Methods:
- Solid-state synthesis method was employed to prepare Ba1-x(La0.5Sr0.5)xCo2Fe16O27 hexaferrites.
- Vibrating Sample Magnetometry (VSM) was used to analyze magnetic properties.
- Vector Network Analyzer (VNA) was utilized to measure magnetoelectric properties and calculate reflection loss from 1-18 GHz.
Main Results:
- W-type hexaferrite structure was observed for x < 0.4, with M-type and spinel phases appearing at higher doping levels.
- Maximum saturation magnetization (Ms) of 76.2 emu/g and minimum coercivity (Hc) of 60 Oe were achieved at x = 0.4.
- Optimized La-Sr doping introduced porosity and increased grain size, enhancing electromagnetic wave dissipation and shifting resonance frequencies to lower bands (C, X, Ku).
- Minimum reflection loss of -40.61 dB at 1.5 mm thickness (X band) for x = 0.2 and -37.45 dB at 2.5 mm (C band) for x = 0.4 were recorded.
- Good absorption was observed for x = 0.6 in X and Ku bands with thickness < 2 mm.
Conclusions:
- La-Sr co-doping effectively tunes the microwave absorption characteristics of Co2W ferrite.
- The prepared materials exhibit excellent electromagnetic wave absorption capabilities, particularly in the C, X, and Ku bands.
- These La-Sr co-doped Co2W ferrites are promising candidates for advanced microwave absorbing applications due to their simple preparation and superior performance.
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