ABTiO3

ABTiO3 refers to a family of titanate perovskites with the general formula ABO3, where A is a relatively large cation such as Ba2+, Sr2+, Ca2+ or Pb2+, and B is Ti4+. In the ideal ABO3 perovskite, Ti occupies the center of an oxygen octahedron (TiO6) and the A cation sits in a larger void formed by the framework of corner-sharing TiO6 octahedra. The structure is flexible and can accommodate distortions that give rise to ferroelectric, dielectric, and piezoelectric properties.

Representative members include BaTiO3, SrTiO3, CaTiO3 and PbTiO3. BaTiO3 is a classical ferroelectric with a sequence of temperature-induced phase transitions and a room-temperature tetragonal phase that supports spontaneous polarization. PbTiO3 is another strong ferroelectric with a higher Curie temperature. SrTiO3 is paraelectric at room temperature and has a very large dielectric constant; under epitaxial strain, doping, or extreme conditions it can exhibit ferroelectric-like behavior. CaTiO3 tends to show less ferroelectric behavior and adopts orthorhombic distortions at room temperature. Variation of A-site composition and B-site chemistry (for example doped BaTiO3) enables tuning of dielectric constant, loss, and ferroelectric properties.

Applications and significance: ABTiO3 materials are widely used in capacitors, tunable dielectric devices, pyroelectric and piezoelectric sensors and actuators, and as components in non-volatile memories. They are actively studied for their dielectric and ferroelectric phase transitions, thin-film ferroelectricity, and integration in electronic devices. Synthesis methods include solid-state reactions, sol-gel processing, and thin-film deposition techniques such as pulsed laser deposition and chemical vapor deposition, which allow control of phase, grain size, and strain.