Fabrication of ZnFe₂O₄/C@PPy composites with efficient electromagnetic wave absorption properties

Nowadays, ferrites/carbon fibers have attracted considerable attention as microwave absorption materials (MA) due to the synergistic effect between dielectric and magnetic loss. Herein, the ZnFe₂O₄/C fibers were fabricated via electrospinning and calcination methods, and then polypyrrole (PPy) successfully coated on the fibers via oxidative polymerization. The ZnFe₂O₄/C@PPy composites exhibit enhanced EM wave absorption performance with the loading of 25 wt%. The optimal reflection loss (RL) value is up to -66.34 dB (13.80 GHz) and effective absorption bandwidth (EAB) is 5.74 GHz (11.78-17.52 GHz) with a matching thickness of 1.93 mm. Besides, high-efficient absorption performance of the ZnFe₂O₄/C@PPy composites is mainly attributed to the dielectric loss and ideal impedance matching. This study reveals a novel approach to development of ferrites/carbon fibers coated with PPy, and the ZnFe₂O₄/C@PPy composites exhibit great potential application as the materials with high-efficient absorption properties.