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Updated: Jul 14, 2026
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Synthesis and Characterization of Fe-doped Aluminosilicate Nanotubes with Enhanced Electron Conductive Properties
Published on: November 15, 2016
Study on Broadband and High-Performance Microwave-Absorbing Spinel NiCo2O4 Regulated by Fe Doping.
Yuanyuan Lv1, Yujia Liu1, Danyang Bai1
1School of Communication and Information Engineering, Xi'an University of Science and Technology, Xi'an 710054, China.
Nanomaterials (Basel, Switzerland)
|July 13, 2026
Summary
Iron doping enhances spinel nickel cobalt oxide (NiCo2O4) microwave absorption by improving conductivity and impedance matching. Optimized 6% Fe doping yields excellent performance with a -62.7 dB reflection loss and 4.6 GHz bandwidth.
Area of Science:
- Materials Science
- Nanotechnology
- Electromagnetics
Background:
- Spinel NiCo2O4 is a promising microwave absorber but suffers from low conductivity and poor impedance matching.
- High-frequency electromagnetic wave absorption requires strong electromagnetic attenuation and broad absorption bandwidth.
- Fe3+ doping offers a strategy to tune dielectric and magnetic properties of NiCo2O4.
Purpose of the Study:
- To investigate the effect of Fe3+ doping on the microstructure, electronic structure, and microwave absorption properties of NiCo2O4.
- To optimize the Fe doping concentration for enhanced microwave absorption performance.
- To elucidate the structure-performance relationship in Fe-doped NiCo2O4.
Main Methods:
- Hydrothermal-calcination synthesis of pristine and Fe-doped NiCo2O4 (4%, 6%, 8% doping).
- Systematic investigation of microstructure, electronic structure, and electromagnetic properties.
- Evaluation of microwave absorption performance, including reflection loss and effective absorption bandwidth.
Main Results:
- Moderate 6% Fe doping (F6 sample) resulted in a refined porous nano-agglomerate structure.
- Fe doping introduced oxygen vacancies and balanced mixed-valence states (Ni, Co, Fe), enhancing polarization and losses.
- The F6 sample achieved a minimum reflection loss of -62.7 dB and an effective absorption bandwidth of 4.6 GHz due to synergistic dual-loss mechanisms and superior impedance matching.
Conclusions:
- Fe3+ doping is an effective strategy to improve the microwave absorption performance of NiCo2O4.
- The optimized F6 sample demonstrates excellent microwave absorption capabilities.
- This study provides a reliable approach for designing high-performance spinel-type microwave absorbers.
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