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Chemical solution deposition (CSD) of BaTiO3 (BT) or BT-based thin films relies on using a carboxylic acid and alcohol as the solvents for alkaline-earth carboxylate and transition-metal alkoxide, respectively; however, the esterification reaction of the solvents may lead to in-situ water formation and precipitation. To avoid such an uncontrolled reaction, we developed a route in which ethylene glycol (EG) is used as the solvent for Ba-acetate. The EG-based BT coating solutions are stable for at least a few months. The thermal decomposition of the BT xerogel obtained by drying the EG-based solutions depends on the choice of the solvent for the Ti-alkoxide as well: in the case of EG and 2-methoxyethanol solvents carbon residues are removed at only about 1100 °C, while in the case of ethanol it is concluded at about 700 °C. About 100 nm thick BT films derived from the EG-ethanol solution deposited on platinized silicon reveal dense, crack-free columnar microstructure. They exhibit local ferro- and piezoelectric properties. The macroscopic polarization-electric field loops were obtained up to a quite high electric field of about 2.4 MV/cm. The EG-ethanol based CSD route is a viable alternative to the established acetic acid–alcohol route for BT and BT-based films. [ABSTRACT FROM AUTHOR]

Polycrystalline BaTiO3 thin films were grown solvothermaly on titanium foil by introducing barium hydroxide solution in a Teflon line and allowed to react with the foil during the autoclave process. Different molar concentration of Ba(OH)2 were investigated: 0.5, 1 and 2 mol·L−1 with three heating temperatures: 150, 175 and 200 °C. The films were characterized by XRD and revealed characteristic peaks of BTO with a slight preferential orientation along the [00l] directions. The SEM characterizations showed dense thin films with spherical grains. The relative permittivity is about 400 and dielectric losses below 0.05 in the frequency range 102 to 107 Hz. [ABSTRACT FROM AUTHOR]

The article focuses on the study related to self-polarization of chemical compound Barium titanate (BaTiO3) and flexoelectric effect. Topics discussed includes persistency of ferroelectricity to a few unit cells by ferroelectric oxide thin films, piezoresponse force microscopy was performed to characterize the ferroelectric domain structure, and various factors responsible for the different self-poarlization of ferroelectric thin films.