Sol-gel synthesis and characterization of BaTiO3-doped (Bi0.5Na0.5)TiO3 piezoelectric ceramics

(Bi0.5Na0.5)TiO3 doped with 8 mol% BaTiO3 (BNT-BT0.08) powder was prepared by an acetate-alkoxide sol-gel method. The evolution of the structure and microstructure of the precursor gel, heated at vari- ous temperatures as well as, the piezoelectric and ferroelectric properties of BNT-BT0.08 ceramics were studied. Nanopowder of BNT-BT0.08 with average particles size of 30 nm and, crystallized on the per- ovskitic structure of (Bi0.5Na0.5)TiO3, were obtained from the precursor gel by heating at 600 oC, 3 h in air. The ceramics of composition 0.92(Bi0.5Na10.5)TiO3-0.08BaTiO3, manufactured from the as-prepared nanostructured powder, present good dielectric properties (?r,max = 4000-4500, tan ? = 0.02-0.03) and high mechanical quality factor (Qm ~ 500).