Ba(Zn1/3Nb2/3)O-3 ceramics synthesized by spray pyrolysis technique

Ba(Zn1/3Nb2/3)O-3(BZN) powder has been prepared by pyrolyzing the polyester precursors, followed by heat treated at 800 degrees C for 4 hrs in air to remove the residual organic materials. The as prepared powders are of hollo w geometrical spheres, which inherit the morphology of the atomized droplet s. The perovsike structure is indicated by X-ray diffraction pattern to hav e already formed. A second phase, identified as Ba5Nb4O15, is observed amon g the pellets sintered at 1250 degrees C similar to 1350 degrees C in open air, which is ascribed to the loss of ZnO. When the pellets were packed wit h ZnO powders and placed in a covered Al2O3 crucibles, pure perovsike, free of Ba5Nb4O15 phase, was obtained when sintered at 1300 degrees C. Q.f valu e as high as 180,000 GHz was achieved for thus obtained BZN.