Hierarchically three-dimensional ZrO2/Fe3O4/C nanocomposites with Janus structure for high-efficiency electromagnetic wave absorption

Hierarchically three-dimensional (3D) materials present a pivotal challenge and opportunity in achieving effective microwave absorption with synergistic effects. In this work, α -Fe 2 O 3 @ZrO 2 with core-shell structure were fabricated in-situ on aramid nanofibers by a solvothermal method . Following calcination , 3D ZrO 2 /Fe 3 O 4 /C nanocomposites with Janus structure have been successfully synthesized. By controlling the lattice match and mismatch in both processes, a core-shell structure of α -Fe 2 O 3 @ZrO 2 and Janus structure of ZrO 2 /Fe 3 O 4 have been well-define performed. The composite material ZrO 2 /Fe 3 O 4 /C-700 has a minimum reflection loss (RL min ) of −67.4 dB at a thickness of 2.0 mm. The effective absorption bandwidth (EAB) at a thickness of 2.4 mm is 6.0 GHz (11.0–17.0 GHz). This study provides a novel strategy for fabricating high-efficiency electromagnetic wave absorption materials with dual synergistic effects in nanosized scale.