To synthesize uniform SrCO3 and BaCO3 nanoparticles, each 0.005 mol of M(NO3)2 (M2+ = Sr2+ and Ba2+) and Na2CO3 as starting materials was mixed in 50 ml ethylene glycol (EG) with 30 min stirring at room temperature. The solutions were transferred into 125 ml flasks, each of which was put in a domestic microwave oven (2.45 GHz) at a time. They were heated by a CMR at 20% of 180 W for 20 min. Each cycle, the microwave oven was on for 24 s every 96 s interval. At the conclusion, white precipitates were synthesized. Concurrently, the same solutions as the above were stirred for 24 h at room temperature without the use of the microwave radiation until white precipitates were achieved. All the products were washed with distilled water and absolute ethanol, dried in air at 80 1C for 24 h, and collected for further characterization by X-ray powder diffraction (XRD),transmission electron microscopy (TEM), selected area electron diffraction (SAED) and Fourier transform infrared (FTIR)spectroscopy.