Investigation of synthesis and magnetic property of rod-shaped NiFe2O4 via chemical precipitation-topotactic reaction employing needle-like γ-FeOOH and α-FeOOH as templates

Using γ-FeOOH and α-FeOOH as template materials rod-shaped NiFe2O4 were prepared by chemical precipitation-topotactic reaction method. A comparison was made on their precursors, synthesis processes and final calcinated products. The results showed that the rod-shaped NiFe2O4 prepared from needle-like γ-FeOOH and α-FeOOH experienced different formation routes, and their crystallinity and morphology depend on the formation routes. The rod-shaped NiFe2O4 prepared from α-FeOOH shows a higher saturation magnetization, and the crystallinity plays an important role in its magnetic performance.