Iron oxide nanoparticles synthesized by coprecipitation method: Impacts of zinc doping and surface functionalization by polyvinylpyrrolidone on the magnetic properties and heating efficiency

Magnetic nanoparticles (NPs) are promising agents for magnetic hyperthermia (MH) due to their ability to convert electromagnetic energy into heat. Their high stability in solution, which is essential to prevent aggregation and ensure uniform distribution as well as their high specific absorption rate (SAR) and intrinsic loss power (ILP) values are especially important in magnetic hyperthermia. This study explores how doping iron oxide NPs with zinc and surface functionalizing them with polyvinylpyrrolidone (PVP) affects their magnetic and heating properties. The saturation magnetization (MS) of ZnxFe3-xO4 NPs at 50 K increases from 76 to 93.5 emu/g corresponding with increasing Zn content from x = 0 up to 0.20, and conversely their coercivity (HC) decreases from 135 down to 77 Oe. For PVP coated NPs, MS is reduced by the presence of nonmagnetic PVP, whereas their HC is increased due to reduced interparticle interactions. Furthermore, the high stability of PVP coated Zn 0.20 Fe 2.80 O 4 NPs in solution is confirmed by the Zeta potential of 46 mV. Notable, high SAR of 460 W/g and ILP of 4.04 nH m2/kg values make them potential candidates for MH applications.