Synthesis of Ppy@ba0.5sr0.5fe12o19/Cnfs by Reverse In-Situ Polymerization Method for Microwave Absorption Applications

Abstract

PPy@Ba0.5Sr0.5Fe12O19/CNFs particles were successfully synthesized through two-steps. First, Barium strontium ferrite (Ba0.5Sr0.5Fe12O19) was deposited on carbon nanofiber (CNFs) via the sol-gel method and second, Polypyrrole (PPy) was coated on Ba0.5Sr0.5Fe12O19/CNFs powders via reverse in-situ polymerization. The Polyurethane-PPy@Ba0.5Sr0.5Fe12O19/CNFs composites were prepared for the microwave absorption test in the X-Band. The morphology and phase evaluation for PPy@Ba0.5Sr0.5Fe12O19/CNFs were carried out using field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). The magnetic parameters of particles were determined via using vibrating sample magnetometer (VSM). The dielectric and magnetic parameters of composites were evaluated by the vector network analyzer (VNA) in the frequency range of 8.2-12.4 GHz. It was seen that the PPy coating decreased the magnetization values while increasing the dielectric values of Ba0.5Sr0.5Fe12O19/CNFs. The minimum R-L value was obtained at lower thicknesses with composite containing 2:1 PPy to Ba0.5Sr0.5Fe12O19/CNFs. The results showed that PPy conductive shell provided the lowest R-L values while causing narrow bandwidth.