Barium ferrite (BaFe₁₂O₁₉) is considered as potential microwave absorption (MA) material thanks to the large saturation magnetization, high Curie temperature, and excellent chemical stability. The integration of carbon nanotube (CNT) can improve the dielectric loss of BaFe₁₂O₁₉ for further enhanced MA performance, nevertheless, the MA performance is still not desirable because of the poor CNT dispersion in the CNT/BaFe₁₂O₁₉ composites, which usually prepared via the ball-milling method, unless high CNT loading was used. Herein, according to the thermal stability of CNT in different atmosphere and the formation mechanism of BaFe₁₂O₁₉ from precursor, CNT was introduced in the precursor of BaFe₁₂O₁₉ uniformly during auto-ignition process and calcined under different atmosphere. When CNT loading is only 2.0 wt%, the CNT/BaFe₁₂O₁₉ composites obtained exhibits a minimum reflection loss ($\mathrm{R}{\mathrm{L}}_{\min }$) of -43.9 dB and effective bandwidth (with $\text{RL}$ < -10 dB) of 3.9 GHz with the thickness of 1.5 mm, which are much superior to -10.2 dB and 2.2 GHz for pure BaFe₁₂O₁₉, and -13.6 dB and 2.5 GHz for CNT/BaFe₁₂O₁₉ composite prepared by ball-milling method. These results may pave the way to design high-performance BaFe₁₂O₁₉ based microwave absorbers.

由于大饱和磁化强度、高居里温度和优异的化学稳定性，钡铁氧体 (BaFe ₁₂ O ₁₉ ) 被认为是潜在的微波吸收 (MA) 材料。碳纳米管 (CNT) 的集成可以改善 BaFe ₁₂ O ₁₉的介电损耗，从而进一步增强 MA 性能，但是，由于 CNT/BaFe ₁₂ O ₁₉复合材料中CNT 的分散性较差，MA 性能仍然不理想，通常通过球磨法制备，除非使用高 CNT 负载量。在此，根据 CNT 在不同气氛中的热稳定性和 BaFe ₁₂ O的形成机制₁₉从前驱体中，CNT 在自燃过程中均匀地引入 BaFe ₁₂ O ₁₉前驱体中，并在不同气氛下煅烧。当CNT负载仅为2.0 wt%时，所获得的CNT/BaFe ₁₂ O ₁₉复合材料表现出最小的反射损耗（$\mathrm{电阻}{\mathrm{升}}_{\mathrm{分钟}}$) 的 -43.9 dB 和有效带宽（与 $\text{强化学习}$< -10 dB) 3.9 GHz，厚度为 1.5 mm，远优于纯 BaFe ₁₂ O _{19 的}-10.2 dB 和 2.2 GHz ，以及由以下方法制备的CNT/BaFe ₁₂ O ₁₉复合材料的-13.6 dB 和 2.5 GHz球磨法。这些结果可能为设计高性能 BaFe ₁₂ O ₁₉基微波吸收器铺平道路。