The heating efficiency of magnetic nanoparticles under an alternating magnetic field

Hysteresis loss and relaxation loss are the two dominant heating mechanisms of magnetic nanoparticles (MNPs) in an alternating magnetic field (AMF). In magnetic induction hyperthermia, heating efficiency is one of the crucial factors. It is proposed that the MNPs with a dominant heating mechanism of relaxation loss will exhibit a higher heating efficiency. However, the relative experiments supporting the proposal is still absent due to the difficulty of obtaining the MNPs with the same components and similar morphology but different dominant heating mechanism. Here, the post-processing method of calcination is employed to change the cation distribution of the MNPs (Fe3O4 and Zn0.54Co0.46Cr0.6Fe1.4O4), so as to obtain the MNPs with similar morphology but different dominant heating mechanism. The magnetic heating experiments were conducted to examine the heating efficiency. The results suggest that the MNPs with relaxation loss have a higher heating efficiency under the investigated AMF.