Xiaohui Cao

Investigation of synthesis and magnetic properties of plate-shaped Zn 2 W ferrites prepared via chemical co-precipitation and sol–gel auto-combustion

Plate-shaped Zn2W ferrites were prepared by chemical co-precipitation method and sol–gel auto-combustion method, respectively, and their precursors, calcination processes and final products were comparatively studied. The results showed the Zn2W ferrites prepared by chemical co-precipitation method and sol–gel auto-combustion method to present different crystallinities, radial sizes, and aspect ratios, which originate from the preparation procedure of the precursors and formation routes of Zn2W ferrites. The magnetic measurement confirmed that the Zn2W ferrite prepared by sol–gel auto-combustion method presents higher saturation magnetization and coercivity, and the analysis indicated that the crystallinity of Zn2W ferrite plays an important role to achieve better magnetic performance.Graphical abstract

Investigation of Synthesis and Magnetic Properties of Rod-Shaped CoFe 2 O 4 via Precipitation–Topotactic Reaction Employing α-FeOOH and γ-FeOOH As Templates

Rod-shaped CoFe2O4 was prepared by chemical precipitation–topotactic reaction method, and in this preparation needle-like γ-FeOOH and α-FeOOH were synthesized to use as template materials. The evolution of phase and morphology in the process of calcination exhibits that α-FeOOH and γ-FeOOH experienced different routes to form the α-Fe2O3 middle phase with different crystallinity and morphology. The synthesis process of CoFe2O4 revealed that the crystallinity, purity and morphology of CoFe2O4 depend on the α-Fe2O3 middle phase. The magnetic measurement showed that the CoFe2O4 prepared from α-FeOOH has higher saturation magnetization and coercivity, and the crystallinity and morphology may play important roles in achieving a better magnetic performance.