Undoped and M-doped ZnO (M Co, Mn) nanopowders have been successfully synthesized by
microwave-assisted approach using Zn(NO3) 2.2H2O and NaOH. The results obtained from X-ray
diffraction (XRD) analysis and the transmission electron microscopy (TEM) showed that the mean particle
size was about 10-15 nm. The XRD analysis of the synthesized samples also showed a single phase ZnO
structure without any additional phase. Magnetic property studies of the as-prepared M-doped ZnO (M Co,
Mn) samples showed them to be paramagnetic material. However, thermal annealing in air of particular
samples at 800?C for 3 h resulted in transforming the samples into a room temperature ferromagnetic
material. ?? 2009 IOP Publishing Ltd.
