Nd doping of bismuth ferrite to tune electromagnetic properties and increase microwave absorption by magnetic-dielectric synergy

Simultaneously achieving tunable electromagnetic parameters and strong absorption capacity in a single material is still a great challenge. Here, we present Nd doped BiFeO₃ with electromagnetic matching, which exhibits tunable electromagnetic properties and high-performance microwave absorption. The experimental and calculated results demonstrate that Nd doping generates the ordered domain structure and changes the coupling states of electrons, which induce difficult polarization rotation and strong natural ferromagnetic resonance, leading to the decrease of dielectric loss and the increase of magnetic loss with increasing Nd concentration. The electromagnetic parameters are tuned from mismatching to matching, and the microwave absorption is improved. Bi_0.8Nd_0.2FeO₃ exhibits a remarkable reflection loss (RL) of -42 dB and bandwidth (RL ≤ -10 dB) which covers nearly three quarters of the X-band at a thickness from 1.9 to 2.1 mm. This work highlights the applications of BFO as a high-performance microwave absorber and opens up a promising feasible route to the development of microwave absorbers in imaging, healthcare, information safety and military fields.