Optimization of Zn(x)Fe(3-x)O₄ hollow spheres for enhanced microwave attenuation

We report here the composition optimization of Zn(x)Fe(3-x)O4 hollow nanospheres for enhancing microwave attenuation. Zn(x)Fe(3-x)O4 hollow nanospheres were synthesized through a simple solvothermal process. The maximum magnetization moment of 91.9 emu/g can be obtained at x = 0.6. The composite filled with Zn0.6Fe2.4O4 exhibited the bandwidth of 3.21-8.33 GHz for RL < -10 dB and a maximum relative bandwidth (Wp,max) of 88.6% at optimized thickness t0 = 0.34 cm. The enhancement should be attributed to the enhanced permeability resonance at high frequency. This optimized hollow material is very promising to be used as a mass efficient and broadband microwave attenuation material.