Articles
  • The influence of lattice defects on the crystal structure of hydrothermal BaTiO3 powders 
  • Xuezheng Wei* and Yali Lia
  • 107 Metals Development, Ames Laboratory, Iowa State University, Ames, Iowa 50011, USA a 322 Spedding, Ames Laboratory, Iowa State University, Ames, Iowa 50011, USA
Abstract
Fine powders of Barium titanate (BaTiO3) were hydrothermally prepared and heat treated at various temperatures from 400 oC to 1200 oC for 1 hour. The as-prepared and heat-treated powders were characterized by thermogravimetric analysis (TGA), Raman spectroscopy, and X-ray diffractometry (XRD). All these powders were identified as tetragonal phase by Raman spectroscopy. The XRD results show that the tetragonality or c/a ratio in heat-treated BaTiO3 powders increases with heat treatment temperature. This suggests that lattice water and lattice vacancies suppress the phase transition from cubic to tetragonal in hydrothermal BaTiO3 powders, but do not prevent it completely.

Keywords: Crystal structure, Lattice defects, Hydrothermal, Barium titanate, powder

This Article

  • 2005; 6(3): 250-254

    Published on Sep 30, 2005