Solid-phase synthesis and study of the structural, optical, and photocatalytic properties of the ATiO3, A = Ca, Sr, Ba ceramic

This paper presents the results of a study of the structural, optical, and photocatalytic properties of ceramics based on ATiO3 titanates, A = Ca, Sr, Ba. Using the method of X-ray phase analysis, it was found that in the case of ceramics obtained from a mixture of BaCO3 and TiO2 after annealing, the structure is a mixture of two phases, rhombohedral BaTiO3 and impurity orthorhombic BaTi4O9. In the case of ceramics obtained from a mixture of CaCO3 and TiO2, the structure is a mixture of two phases of the orthorhombic phase and rutile TiO2. In the case of ceramics obtained from a mixture of SrCO3 and TiO2, the structure is a mixture of two phases of the SrTiO3 orthorhombic phase and the Ti2O5 orthorhombic phase. At the same time, all synthesized ceramics have a high crystallinity degree and order of the crystal structure. An analysis of the optical properties showed that the main changes are associated with the difference in the band gap, which is due to the presence of different phases in the structure of ceramics. Based on the results of photocatalytic reactions, the order of photocatalytic activity of the synthesized ceramics was determined: SrTO3/T2O5 > CaTO3/TO2 > BaTO3.