title: The dependence of Ni-Fe bioxide composites nanoparticles on the FeCl2 solution used.
abstract: BACKGROUND
  Ni2O3- γ-Fe2O3 composite nanoparticles coated with a layer of 2FeCl3·5H2O can be prepared by co-precipitation and processing in FeCl2 solution. Using vibrating sample magnetometer (VSM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) diffraction techniques, the dependence of the preparation on the concentration of the FeCl2 treatment solution is revealed.
  
  
  RESULTS
  The magnetization of the as-prepared products varied non-monotonically as the FeCl2 concentration increased from 0.020 M to 1.000 M. The Experimental results show that for the composite nanoparticles, the size of the γ-Fe2O3 phase is constant at about 8 nm, the Ni2O3 phase decreased and the 2FeCl3·5H2O phase increased with increasing concentration of FeCl2 solution. The magnetization of the as-prepared products mainly results from the γ-Fe2O3 core, and the competition between the reduction of the Ni2O3 phase with the increase of the 2FeCl3·5H2O phase resulted in the apparent magnetization varying non-monotonically.
  
  
  CONCLUSIONS
  When the concentration of FeCl2 treatment solution did not exceed 0.100 M, the products are spherical nanoparticles of size about 11 nm; their magnetization increased monotonically with increasing the concentration of FeCl2 solution due to the decreasing proportion of Ni2O3 phase.
authors.affiliation: School of Physical Science &Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing, 400715, People's Republic of China. aizhong@swu.edu.cn.
authors.forename: Yueqiang
authors.initials: Y
authors.lastname: Lin
authors.forename: Jian
authors.initials: J
authors.lastname: Li
authors.forename: Lihua
authors.initials: L
authors.lastname: Lin
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Liu
authors.forename: Longlong
authors.initials: L
authors.lastname: Chen
authors.forename: Jun
authors.initials: J
authors.lastname: Fu