Preparation and microwave absorbing property of Ni–Zn ferrite-coated hollow glass microspheres with polythiophene

• This manuscript synthesized HMG/Ni0.7Zn0.3Fe2O4/PT composites.
• The surface morphology, electrical property, magnetic performance and reflection loss of the composites were measured.
• This paper also analyzed the relationship between the reflection loss of the absorber and its thickness.

The composite of hollow glass microspheres (HMG) coated by Ni0.7Zn0.3Fe2O4 particles was fabricated via sol–gel method, and then the ternary composite (HMG/Ni0.7Zn0.3Fe2O4/PT) was synthesized by in situ polymerization. The electrical property, magnetic performance and reflection loss of the composites were measured, and the results suggest that the conductivity and the saturation magnetization (Ms) of HMG/Ni0.7Zn0.3Fe2O4/PT reach 6.87×10−5 S/cm and 11.627 emu/g, respectively. The ternary composite has good microwave absorbing properties (Rmin=−13.79 dB at 10.51 GHz) and the bandwidth less than −10 dB can reach 2.6 GHz (from 9.4 to 12.0 GHz) in X band (8.2–12.4 GHz). The morphology and chemical structure of the samples were measured through scanning electron microscopy (SEM), X-Ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). This paper also analyzes the relationship between the reflection loss of the absorber and its thickness.