Microstructural properties of lead free BiMnO3 ceramic prepared by mechanochemical synthesis

The present paper reports the synthesis of BiMnO3 (BMO) using Bi2O3 and Mn2O3 as initial powder mixture through mechanochemical synthesis route by a planetary ball milling. The powder mixture was intensively milled in atmospheric temperature to achieve crystalline powder of BiMnO3 (BMO). For structural analysis of the sample the X-ray diffraction (XRD) and Scanning electron microscopy (SEM) investigation was carried. The XRD analysis clearly shows the single phase perovskite structure having monoclinic symmetry with lattice parameter a=5.883A, c=7.525A and space group P121/C1. SEM images confirm the achievement of polycrystalline morphology of BMO ceramic with visible grain boundary. It is also found that the presence of agglomerated structure was reduced as the milling time increases. The particle size of starting BMO was somewhat proportional to the grain size. The enhancement in the values of relative density from 90% to 97% of the resulting ceramics was recorded when the sample milling time increases from 1h to 20h. Eventually, the dielectric characteristics of the BMO sample were studied. The dielectric behaviour at room temperature to a temperature of 200 degrees C has been reported. The properties of the prepared ceramic powder signify for potential application as a multiferroic material with simultaneous control over piezoelectric and dielectric characteristics.