Heterointerface engineering in Cr 2 GaC/C hybrids through bottom-up template synthesis for enhanced electromagnetic wave absorption

MAX phases are emerging as efficient electromagnetic wave absorption (EMA) materials, favored for their outstanding conductivity, high-temperature stability, and corrosion resistance. However, the limitations of a singular energy loss mechanism and the need for a high filler ratio hinder their further development. Herein, a template method utilizing absorbent cotton as a carbon source was employed to synthesize 0D/1D Cr 2 GaC/C hybrid materials. The bottom-up preparation strategy maintains the size of the Cr 2 GaC MAX-phase particles at ∼200 nm while ensuring their uniform distribution within the carbon fibers. The abundant heterointerfaces between Cr 2 GaC and carbon enhanced interfacial polarization, while the carbon fiber network improved conduction loss. Consequently, the Cr 2 GaC/C hybrid exhibits excellent EMA properties, achieving a minimum reflection loss value of −59.0 dB at a thickness of only 1.56 mm and an ultra-low filler content of 15 wt%. Additionally, its maximum radar cross section reduction value is 17.78 dB m 2 , showing excellent stealth capability. This research provides new insights into the nanoscale synthesis of MAX phases and offers promising pathways for optimizing their EMA performance.