Microwave absorption properties of multiferroic BiFeO₃ nanoparticles

Multiferroic BiFeO₃ (BFO) nanoparticles ranging from 60 nm to 120 nm were synthesized successfully by a sol-gel method, and the microwave absorption properties of BFO nanoparticles were investigated in the range of 12.4 GHz to 18 GHz. The reflection loss of BFO nanoparticles is more than 10 dB (or more than 90%) in the 13.1 GHz-18 GHz range and reaches to 26 dB at 16.3 GHz, which indicated that the BFO is a good candidate for microwave absorption application. The excellent microwave absorption properties of BFO nanoparticles could be attributed to the good electromagnetic match as a consequence of the coexistence of ferroelectric and weak ferromagnetic order in BFO nanoparticles, which has been confirmed by electric and magnetic measurement. Moreover, the nanosize-confinement effect may also have contribution to the high reflection loss of BFO nanoparticles.