Preparation and property of polyaniline nanofibers/lithium zinc ferrite composite absorbents

Lithium zinc ferrite(Li_0.435Zn_0.195Fe_2.37O₄, LZFO) was prepared by sol-gel method and interfacial polymerization method was used to prepare pure polyaniline(PANI) and PANI nanofibers/LZFO composites. The phase, structure and microwave absorption property of the materials were analyzed and characterized by SEM, XRD, FTIR and vector network analyzer(PNA). The results show that the samples are PANI, LZFO and different ratio of PANI nanofibers/LZFO composites. In the range of 2-18 GHz, PANI nanofibers/LZFO composites emerge two bands corresponding to electromagnetic wave reflection loss below -10 dB. The PANI nanofibers enhance the wave-absorbing property and widen the wave-absorbing band of PANI nanofibers/LZFO composites compared with PANI and LZFO. When the mass fraction of PANI nanofibers for PANI nanofibers/LZFO composites is 10%, the composites get the best comprehensive wave-absorbing properties. The peak of absorption could reach -33.8 dB and the bands corresponding to electromagnetic wave reflection loss below -10 dB lay in 2.5-5.5 GHz and 14.5-16.5 GHz. While the PANI and LZFO only emerge one band corresponding to electromagnetic wave reflection loss below -10 dB. Therefore, the electromagnetic parameter is adjusted and the microwave absorption property improves through grafting PANI nanofibers with ferrite.