Electromagnetic and microwave absorption properties of the core-shell structured C@BaMg0.2Co0.8TiFe10O19 nanoparticles

BaMg0.2Co0.8TiFe10O19 (BMCTF) hexaferrite was synthesized via sol-gel combustion reaction method, and the magnetic-dielectric heterostructured nanoparticles C@BMCTF was prepared by a combination of hydrothermal carbonization and carbothermal reduction processes (BMCTF as the core and carbon as the shell). From XRD, RAMAN, FE-SEM and HRTEM, the core-shell structure of C@BMCTF was confirmed and the average grain size of the particles was around 100-300 nm. Based on the static magnetic measurement, the coercivity (H-c) was increased and the saturation magnetization (M-s) was decreased with the coating of carbon. Moreover, the maximum reflection loss (RL) could reach -45.2 dB with a matching thickness of 1.8 mm from the electromagnetic parameters measured by vector network analyzer, and also the bandwidth of RL <= -10 dB could cover the whole Ku band, which indicated the excellent absorbing properties of C@BMCTF.