High heating ability of one-step carbothermal reduction method of Fe₃O₄ nanoparticles upon magnetic field

Induction heating Fe₃O₄ nanoparticles are commonly used in magnetic hyperthermia. For the best comprehensive efficiency, particles are needed which possess the highest possible heating rates/specific absorption rate when being exposed to a magnetic field. In this paper, a fail one-step carbothermal reduction method for magnetic nanoparticles is optimized towards yielding Fe₃O₄ nanoparticles with small-size (6.5 ± 2 nm), strong magnetism (90.2 emu·g⁻¹), and high heating rates. The parameters of alternating magnetic field are studied in depth to understand how to produce the best heating rates. Hyperthermia measurements were performed under an alternating magnetic field with a frequency of 165.3 kHz, 245.6 kHz and calculated the specific absorption rate. The optimum specific absorption rate is 43.5 W·g⁻¹ at 15 mT and 245.6 kHz. The maximum intrinsic loss power (ILP) value is 3.8 nHm²·kg⁻¹.