Polymer-Derived Lightweight SiBCN Ceramic Nanofibers with High Microwave Absorption Performance

Area of Science:

• Materials Science
• Nanotechnology
• Ceramic Engineering

Background:

• Development of advanced materials for electromagnetic wave absorption is crucial for modern defense and commercial technologies.
• Tailoring material properties at the nanoscale is key to achieving desired functional characteristics like microwave absorption.

Purpose of the Study:

• To prepare lightweight silicon boron carbon nitride (SiBCN) ceramic nanofibers with tunable electromagnetic wave absorption properties.
• To investigate the effect of annealing temperature on the microstructure and microwave absorption performance of SiBCN nanofibers.

Main Methods:

• Electrostatic spinning was employed to fabricate SiBCN nanofibers.
• High-temperature annealing was used to control nanoscale architectures and atomic bonding structures, with a specific focus on annealing at 1600 °C.

Main Results:

• SiBCN nanofibers annealed at 1600 °C were defect-free, composed of an amorphous matrix with β-SiC and free carbon nanocrystals.
• These nanofibers demonstrated excellent microwave absorption, achieving a minimum reflection coefficient of -56.9 dB at 10.56 GHz.
• A maximum effective absorption bandwidth of 3.45 GHz was recorded with a sample thickness of 2.6 mm and a maximum dielectric constant of 0.44.

Conclusions:

• Optimized A + B + C microstructure in SiBCN ceramic nanofibers leads to satisfying microwave absorption properties.
• These SiBCN nanofibers are promising candidates for lightweight, ultrastrong radar wave absorbers.
• The findings support the potential application of these materials in both military and commercial markets.