A self-organized nanostructure induced by phase separation in NiCuZn-ferrites

Transmission electron microscopy investigation revealed a phase separation in the NiCuZn ferrites. In a cubic (Ni,Zn)Fe2O4 matrix precipitates of the cubic Fe0.64Ni0.36 were found constructing an almost periodic array of nanowires. The nanowires were grown endotaxially in the matrix, i.e. the corresponding cubic axes of the two structures are almost perfectly parallel one to the other, with deviations smaller than 1°. Moreover the interfaces between the matrix and the precipitates are very well defined crystallographic planes, mainly parallel to {1 1 1}. These features of the nanowires allow them to be considered as a self-organized nanostructure.