Topological designed Fe3O4@C/rGO gradient architecture with enhanced microwave absorption

Microstructure and composition are critical strategies to obtain high-performance electromagnetic wave (EMW) absorbing materials. In this study, Fe 3 O 4 @C and Fe 3 O 4 @C/rGO were synthesized by the hydrothermal method. Subsequently, a gradient structure was designed to further optimize the EMW absorption performance of composition using CST software. The electromagnetic parameters of the EMW absorbing materials were utilized to design the gradient structure by employing a genetic algorithm to determine the optimal thickness. The results indicate that the gradient structure of Fe 3 O 4 @C and Fe 3 O 4 @C/rGO demonstrate exceptional EMW absorption performance with the minimum reflection loss (RL min ) of −50.26 dB at 9.73 GHz and the effective absorption bandwidth (EAB) of 3.86 GHz (2.04 GHz-2.85 GHz, 8.57 GHz-11.62 GHz). Finally, the proposed system was validated using the waveguide method, revealing that the experimental curves align closely with simulated curves, thereby confirming the feasibility of this structure. • Fe 3 O 4 @C and Fe 3 O 4 @C/rGO were synthesized by the hydrothermal method. • The gradient structure is designed by CST software based on the prepared materials. • The EMW absorption performance is verified by the waveguide method. • The RL min of −50.26 dB at 9.73 GHz and the EAB of 3.86 GHz.