Combustion synthesis and characterization of BaTiO₃

An important, somewhat novel procedure for the bulk synthesis of finely divided crystalline BaTiO₃ powder has been studied and is applicable to the synthesis of other compounds in the BaO-TiO₂ system as well. An aqueous solution of Ba(NO₃)₂, TiO(NO₃)₂, and alanine is spray dried. A combustion reaction occurs when heating the product to 300 °C. The reaction converts the spray-dried mixture to BaTiO₃. This BaTiO₃ powder and its sinterability have been characterized by thermal analysis, XRD, SEM, dielectric, and particle size measurements. The powder resulting from the thermal runaway reaction is finely divided and sinters more readily than the conventionally prepared high purity BaTiO₃.