Preparation and characterization of Fe ₃O ₄/T-ZnOw composites

Fe ₃O ₄/T-ZnOw composites are fabricated by depositing a layer of Fe ₃O ₄ film on the surface of tetrapod-shaped ZnO whisker (T-ZnOw) by ferrite plating method. The morphology, structure and magnetic properties of the composites are characterized by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and vibrating-sample magnetometer (VSM), respectively. The effects of temperature and pH value of ferrite plating on the Fe ₃O ₄/T-ZnOw composites and the magnetic properties of composites are studied. It is shown that the chemical environment with pH value at 7.5 is most favorable for the ferrite plating processes by analyzing the main peaks intensity of Fe ₃O ₄ in the XRD patterns and the average diameters of the Fe ₃O ₄ crystalline. The increase of the ferrite plating temperature with pH value around 7.5 benefits the whole encapsulation of T-ZnOw by the Fe ₃O ₄ magnetic films. The composites exhibit ferromagnetic properties and show much lower magnetization intensity than bulk samples at the same magnetic field intensity.