High Energy Milled Ba0.06Na0.47Bi0.47TiO3 Ceramic: Structural and Electrical Properties

The present work reports on the effect of high energy milling on the structural, microstructural, electrical and electrostriction properties of Ba0.06Na0.47Bi0.47TiO3 (BNBT) ceramics prepared using standard solid-state reaction technique. X-ray diffraction studies showed that the unit cell structure of un-milled and milled samples is rhombohedral (space group: R3c). FTIR spectra also indicated the formation of BNBT without any new phase. The 10 h milled BNBT (spherical nanoparticles of 25-50 nm) ceramic showed the formation of small grain sizes (similar to 1.2 mu m) which is advantageous for dielectric applications in high density integrated circuits. Milling could suppress the resonance effect which is beneficial for extending the upper limit if frequency for the use of a capacitor. The correlated barrier hopping model successfully demonstrated the mechanism of charge transport in present ceramic system and ac conductivity data obeyed Jonscher's universal power law. A marked enhancement in the remnant polarization and lowering of the value of coercive field of milled BNBT sample was observed. The electric field dependent polarization and strain studies carried out at room temperature indicated that BNBT nanoceramic might be a propitious lead-free electrostriction material for industrial applications.