Ga-doped NiZnCu ferrite@polyaniline/carbon nanotube ternary composites operating in the C-band and Ku-band exhibit tunable microwave absorption performance
摘要
Due to the poor microwave absorption performance of single-phase ferrite, we attempted to combine it with dielectric materials to prepare a composite material with good microwave absorption performance through the electromagnetic cooperative loss mechanism. The ternary composite material of carbon nanotubes/NZCF ferrite/polyaniline was prepared by a two-step method in this experiment. The dielectric properties and microwave absorption characteristics of the samples were thoroughly analyzed. By testing the electromagnetic parameters, it was found that the CNTs/PANI@Ni0.25Zn0.40Cu0.35Fe1.85Ga0.15O4 composite has a minimum reflection loss of – 49.63 dB at 15.8 GHz and an effective absorption bandwidth of 1.96 GHz. And the authors found that when the doping concentration of Ga3+ increased (0.06 ≤ x ≤ 0.12), the RL(min) value moves to the low frequency, and when the doping concentration of Ga3+ (0.12 ≤ x ≤ 0.15), the RL(min) value moves to the high frequency. In addition to this, it can be clearly observed that when the absorber thickness is 5 mm and 5.5 mm, the reflection peaks appearing in the C-band (4–8 GHz) and Ku-band (14–18 GHz) exhibit approximately symmetric distributions. Therefore, the author believes that the results of this experiment demonstrate that combining ferrite with dielectric materials can yield a composite material with good microwave absorption performance. It was also found that the microwave absorption performance of the CNTs/PANI@Ni0.25Zn0.40Cu0.35Fe2-xGaxO4 composite material can be fine-tuned by adjusting the doping content of Ga3+, to meet the application requirements under both low-frequency and high-frequency conditions.