Phase transformations kinetics in barium titanate synthesis by mechanochemical processing

This article presents the research results on a dry mechanochemical synthesis of barium titanate at a low temperature in which the reaction model and kinetics were determined during the activation of a powder mixture of titanium dioxide and barium oxide. The solid-state reaction achieved high degree of conversion (0.99). Successive analyses were conducted throughout the reaction, revealing the presence of both the starting powders and newly formed intermediate compounds. Phase transformations were monitored via X-ray diffraction, allowing the dynamics of the synthesis to be characterized. It was established that, for the given system, 440 min of mechanical activation in a high-energy vibration mill was required to complete the neutralization reaction and produce barium titanate. The reaction mixture composition was tracked by sampling at five intervals, confirming the presence of intermediate compounds and mapping the reaction pathway from the initial barium and titanium oxides to the final BaTiO3 product.