1. State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou 730050, China;
2. School of Science, Lanzhou University of Technology, Lanzhou 730050, China
Abstract：Pure and Ni-doped Zn1-xNixFe2O4 nanoparticles with different contents were successfully prepared via hydrothermal method. The influence of nickel doping concentration on the microstructure, morphology, optical and magnetic properties of Zn1-xNixFe2O4(x=0,0.1,0.3,0.5) nanocrystals were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction(SAED), X-ray energy dispersive spectroscopy(XEDS),ultraviolet-visible absorption spectrum(UV-Vis), Fourier transform infrared spectroscopy (FT-IR) and the vibrating sample magnetometer (VSM) and etc. The results show that all Zn1-xNixFe2O4 nanoparticles are with good crystallization,Ni2+ enters into ZnFe2O4 lattice in the form of replacing Zn2+,and generating cubic spinel structure ZnFe2O4. With the increase of Ni content, the crystalline size increases and the lattice constant shrinks. The morphology of the samples exhibits irregular ellipsoid with uniform particle size. The absorption peak position of FT-IR spectra does not change with the increase of Ni doping concentration. The energy band gap of Zn1-xNixFe2O4 nanocrystals increases with the increase of Ni doping concentration, and blue shift occurs compared with the corresponding bulk. Pure ZnFe2O4 nanocrystals exhibit super paramagnetic properties and the doped samples show obvious ferromagnetism at room temperature.
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