Ferromagnetism in manganese and cobalt co-doped ZnO bulk samples

The polycrystalline bulk samples with nominal composition Zn1−x(Mn1/2Co1/2)xO (x = 10%, 15%, 30%) were fabricated at 600 °C by the standard solid-state reaction method. The structural analysis shows that the lower doped samples (x < 15%) are single phase of wurtzite structure, while for the high-doped sample (x = 30%), beside the main peaks of wurtzite structure, the peaks of secondary phase are visible. Magnetization measurement indicates that all the samples show ferromagnetic ordering with Tc > 300 K. Based on the structural analyses, the experimental observation is discussed.