The hydrothermal synthesis of BaTiO3 fine particles from hydroxide-alkoxide precursors

Fine powders of barium titanate were synthesized hydrothermally from aqueous barium acetate or barium hydroxide and titanium ethoxide solution, with different alkaline media, ammonia, hydrazine and tetramethylammonium hydroxide. Barium titanate powder prepared from Ba(OH)(2) after synthesis shows BaCO3 impurities. On the other hand, powders prepared from Ba(CH3COO)(2), Ti(OC2H5)(4) and tetramethylammonium hydroxide exhibit the smallest average grain size and did not contain BaCO3 impurities. However, a relative by large amount of organic disintegration products which delay the sintering process were identified in the BaTiO3 powders from Pa acetate. The BaTiO3 powders were characterized by scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), thermogravimetric analysis (TGA), mass spectroscopy and dilatometric analyses. (C) 1998 Published by Elsevier Science Limited.