Enhanced magnetic heating efficiency and thermal conductivity of magnetic nanofluids with FeZrB amorphous nanoparticles

Magnetic heating and thermal conductivity of magnetic nanofluids (MNFs) are of great interest for biomedicine and electronic heat transfer. Here, we report the enhanced magnetic heating efficiency and thermal conductivity of MNFs fabricated by amorphous FeZrB nanoparticles with high saturation magnetization and good magnetothermal stability. Under external magnetic fields, the viscosities of FeZrB MNFs are almost twice that of Fe 3 O 4 MNFs, enhancing the field-driving force in heat transfer applications. Under 250 Oe alternating current fields, the required time of heating FeZrB MNFs to the hyperthermic temperature (45 °C) is only 16.5% that of Fe 3 O 4 MNFs, amplifying the specific absorption rate of the magnetic nanoparticles by about 2.4 times. Benefiting from the higher thermal conductivity of amorphous, the thermal conductivity enhancement for FeZrB MNFs is also larger than that of Fe 3 O 4 MNFs—up to 34.0% enhancement for silicone oil-based FeZrB MNF at φ = 2 vol%. This investigation of amorphous-nanoparticle-including MNFs shall shed light on the potential of utilizing amorphous nanoparticles to fabricate MNFs for biomedicine or heat management applications.