Magnetic ceramics were prepared by pyrolysis of polyferrocenylsilazanes (PZs) with linear-cyclic structure at different temperatures under nitrogen atmosphere. The ceramics was investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM) coupled with EDX. α-Fe nanoparticles (NPs) were found the only magnetic crystalline embedded in the amorphous Si/C/N-based matrix below 700 °C. The increase of temperature to 900 °C resulted in reactions between α-Fe NPs and the surrounded matrix to produce iron silicides. Above 600 °C, the type and size of magnetic crystallines were postulated to be controlled by nucleation of iron and the reaction of iron with matrix. When the temperature is below 900 °C, the nucleation of iron was dominate, which leaded to the growth of the α-Fe NPs, while above 900 °C, the reaction between α-Fe NPs and the matrix produced iron silicide particles and decreased the size of α-Fe NPs.

Magnetic ceramics were prepared by pyrolysis of polyferrocenylsilazanes (PZs) with linear-cyclic structure at different temperatures under nitrogen atmosphere. The ceramics was investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM) coupled with EDX. α-Fe nanoparticles (NPs) were found the only magnetic crystalline embedded in the amorphous Si/C/N-based matrix below 700 °C. The increase of temperature to 900 °C resulted in reactions between α-Fe NPs and the surrounded matrix to produce iron silicides. Above 600 °C, the type and size of magnetic crystallines were postulated to be controlled by nucleation of iron and the reaction of iron with matrix. When the temperature is below 900 °C, the nucleation of iron was dominate, which leaded to the growth of the α-Fe NPs, while above 900 °C, the reaction between α-Fe NPs and the matrix produced iron silicide particles and decreased the size of α-Fe NPs.