Electrochemical route for accessing amorphous mixed-metal hydroxide nanospheres and magnetism

A series of amorphous mixed-metal hydroxide nanospheres with a homogeneous distribution of metals in compositions, including binary Fe-Co, Fe-Ni and Co-Ni hydroxides and ternary Ni-Co-Fe hydroxides, have been for the first time prepared via a simple, facile and green electrochemical technique. The morphology, structure and element distribution of the as-prepared amorphous nanophases were characterized in detail. The magnetic measurements showed that all the as-prepared amorphous nanophases exhibit similar magnetic behaviors for their clear magnetic hysteresis loops and well saturated magnetization, and the amorphous Fe-Co hydroxide nanospheres have the highest saturation magnetization (160.7 emu g(-1)) at room temperature among four amorphous nanophases. These findings pave a way for the applications of amorphous metal hydroxides nanomaterials as magnetic materials.