Effects of Lanthanum Doping on the Microstructure and Electromagnetic Properties of X-Type Hexaferrite Ba2Co2Fe28O46 Prepared by High-Temperature Solid-State Reaction

With the advancement of electronics and communication technologies, there is growing interest in high-performance microwave-absorbing materials. The material composition and structural design are critical factors influencing the electromagnetic wave (EMW) absorption capabilities. X-type barium ferrite (Ba2Co2Fe28O46) exhibits advantages in enhancing high-frequency magnetic loss and interface polarization through its unique hexagonal crystal structure and morphological design, while also optimizing impedance matching to a certain extent. However, the effective absorption bandwidth (EAB) of single-phase barium ferrite is often restricted. Therefore, doping with other elements is necessary to broaden the EAB. In this study, La3+-substituted X-type hexagonal ferrites Ba2Co2Fe28−xLaxO46 (x = 0.00, 0.05, 0.10, 0.15, and 0.20) were successfully synthesized via a high-temperature solid-state reaction method, and the effects of different La3+ doping concentrations on the electromagnetic parameters and wave-absorbing performance of Ba2Co2Fe28O46 were investigated. After doping, the materials demonstrated excellent electromagnetic absorption performance: when x = 0.15, RLmin = −48.36 dB; when x = 0.10, EAB = 9.03 GHz (RL ≤ −5 dB).