Carbon Hollow Microspheres with a Designable Mesoporous Shell for High-Performance Electromagnetic Wave Absorption

Area of Science:

• Materials Science
• Nanotechnology
• Electromagnetics

Background:

• Developing efficient microwave absorbers is crucial for electromagnetic compatibility and shielding.
• Existing materials often face limitations in absorption bandwidth, thickness, or performance.

Purpose of the Study:

• To synthesize and characterize mesoporous carbon hollow microspheres (PCHMs) for electromagnetic wave absorption.
• To evaluate the microwave absorption performance of PCHMs in composite materials.

Main Methods:

• In situ stöber templating and pyrolysis-etching for PCHM synthesis.
• Characterization using electron microscopy, spectroscopy, and gas adsorption.
• Preparation and testing of paraffin/PCHM and phenolic resin/PCHM composites for microwave absorption.

Main Results:

• Uniform PCHMs with a 4.7 nm mesoporous shell and 345 nm cavity were fabricated.
• Paraffin/PCHM composite achieved -84 dB reflection loss at 8.2 GHz with a 3.9 mm thickness.
• Phenolic resin/PCHM composite exhibited an ultrawide effective absorption bandwidth of 8 GHz below -10 dB with a 2.15 mm thickness.

Conclusions:

• PCHMs demonstrate excellent electromagnetic wave absorption properties due to their unique structure.
• The design strategy offers a pathway for developing advanced, lightweight microwave absorbers.
• The fabricated PCHMs show potential as highly effective candidates for microwave absorption applications.