Магнитные наночастицы Zn-=SUB=-x-=/SUB=-Fe-=SUB=-3-x-=/SUB=-O-=SUB=-4-=/SUB=- (0 ≤ x≤ 1.0), функционализированные полиакриловой кислотой (Zn-=SUB=-x-=/SUB=-Fe-=SUB=-3-x-=/SUB=-O-=SUB=-4-=/SUB=-@ПАК)

Abstract

Studies of the properties of ZnxFe3-xO4 (x=0, 0,25, 0,5, 0,75, 1) magnetic nanoparticles synthesized by a modified hydrothermal method are presented in comparison with the properties of the same nanoparticles stabilized with polyacrylic acid ZnxFe3-xO4@PAA. The structure, size, morphology, and magnetic properties of the samples were studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT IR), physical properties measurements (PPMS), and Mossbauer spectroscopy. The synthesized nanoparticles are single-phase, without additional impurities, have a narrow size distribution and are in the superparamagnetic phase. From the RD measurements, it was found that with an increase in the Zn content from x = 0 to x= 1.0, the sizes of nanoparticles increasing from 17 to 33 nm. Analysis of the Mössbauer spectroscopy data showed that when doped with Zn ions from x=0 to x=1.0, the sizes of nanoparticles decreasing from 15 nm to 5 nm. The results of the Mossbauer studies showed that both ZnxFe3-xO4 and ZnxFe3-xO4@PAC has a core/shell type structure in which the core is magnetically ordered, whereas the shell does not have magnetic ordering. Mossbauer studies indicate that the coating of citric acid particles leads to their isolation from each other, a decrease or elimination of interactions between particles, a decrease in the thickness of the paramagnetic shell, and, due to this, an increase in the diameter of the core.