Facial Synthesis of Zn-Doped Fe3O4 with Enhanced Electromagnetic Wave Absorption Performance in S and C Bands

In this study, Zn-doped Fe3O4 nanoparticles were successfully synthesized by a facile solvothermal method in the presence of sodium dodecyl sulfate (SDS). The morphology, magnetic properties and electromagnetic wave absorbing properties of these materials were characterized. Results showed that Zn2+ played a significant role in the formation of Zn-doped Fe3O4. With the protection of SDS, highly dispersed Fe3O4 nanoparticles were obtained. The nanoparticle size decreased after Zn2+ doping, and the dispersity deteriorated with increasing Zn2+ doping concentration. Zn-doped Fe3O4 exhibited excellent electromagnetic wave absorbing property, which resulted in magnetic loss and dielectric loss at an appropriate doping concentration. The minimum reflection loss (RL) was approximately -27.2 dB at 16.9 GHz. As the coating layer thickness increased to 4.0 mm, the bandwidth was approximately 5.0 GHz corresponding to RL below -10 dB, which nearly covered the entire S band (2-4 GHz) and C band (4-8 GHz). The peak frequency of RL and the number of peaks matched the quarter-wave thickness criteria. It was believed that the Zn-doped Fe3O4 could be a potential electromagnetic wave absorbing material in S and C bands.