Excellent Microwave Absorption Behaviors of Polyaniline Composites Containing CeO2 Nanorods in the X-Band

Conductive polyaniline/CeO2 nanocomposite powders (PANI/CeO2) were prepared by an in situ polymerization method. The effects of CeO2 content on the microwave absorption properties of composites were investigated. The phase composition, morphological characteristics, electromagnetic parameters and microwave absorption properties of the composites were characterized through X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and vector network analysis. Results show that CeO2 nanorods are coated with PANI to form a well-defined hierarchical structure. CeO2 is well-incorporated into the PANI matrix. CeO2/PANI exhibits excellent microwave absorption properties at 2-18 GHz. As the CeO2 content increases to 30 wt.%, an optimal reflection loss (RL) of -40 dB (99.99% of electromagnetic wave absorption) is observed at 8.8 GHz with a thickness of 3.0 mm. The frequency bandwidth corresponding to 90% of electromagnetic wave absorption crosses the X-band. Therefore, PANI/CeO2 can be used as an advantageous candidate for a new type of microwave absorptive material.