Modified chemical coprecipitation of magnetic magnetite nanoparticles using linear–dendritic copolymers

In this investigation, magnetite nanoparticles (Fe₃O₄ NPs) with a diameter of 5–10 nm were synthesized by coprecipitation from an alkaline solution of ferrous/ferric mixed salt-solution in the presence of copolymers. In this process, linear–dendritic copolymers containing a linear poly (ethylene glycol) core and dendritic poly (citric acid) arms were used as the stabilizer. The Fe₃O₄ NPs were characterized by transmission electron microscopy, energy-dispersive spectra, X-ray powder diffraction, field emission scanning electron microscopy, Fourier transform infrared spectrometer, and vibrating sample magnetometer. Compared to classical coprecipitation, the results showed that uniform, ultrafine, nearly spherical, and high purity nano-magnetite particles with better magnetic properties could be prepared by this method.