The octahedral,decahedral and star-like Zn0.3Fe2.7O4 nanoparticles were prepared by changing the heating rate,using 4-biphenyl carboxylic acid as a surfactant in the high temperature organic thermal decomposition synthesis,achieving controllable synthesis of nanoparticles morphology growth.Using the reverse microemulsion method,nanoparticles were coated with SiO2 of different shell thicknesses,making them water-soluble,and the specific loss power(SLP)of Zn0.3Fe2.7O4@SiO2 composite nanoparticles under an alternating magnetic field was studied.The results indicate that the heat generation capacity of the nanoparticles decreases with increasing SiO2 shell thickness under high magnetic fields,while it increases with increasing SiO2 shell thickness under low magnetic fields.As the SiO2 thickness increases,the dipolar interactions between the magnetic nanoparticles are reduced,leading to a decrease in the resulting anisotropy.This causes SLP of the magnetic nanoparticles to exhibit different rules under high and low magnetic fields.
关键词
磁性纳米颗粒/高温有机合成/偶极相互作用/磁热性能
Key words
magnetic nanoparticles/high-temperature organic synthesis/dipole interaction/magnetic hyperthermia properties