Ultra-small size and crystal-axis-oriented BaTiO3 nanocrystals: Dielectric and photocatalytic response

Abstract

With the development of modern nanotechnology, the application range of BaTiO3 (BT) materials has been expanded, and the design and synthesis of micro-nano scale BT materials have become one of the hot spots. In this study, ultra-small BaTiO3 (Ultra-BT) were prepared by solvothermal-calcination reaction. First, the BT precursor was prepared by solvothermal reaction with ethylene glycol as solvent, and then the BT precursor was calcined to obtain Ultra-BT. The Ultra-BT at this time is composed of uniform [010]-crystal-axis-oriented BT nanocrystals with a size of about 28 nm. The formation mechanism of Ultra-BT was revealed, namely the dissolution-deposition reaction. Ultra-BT are more favorable for the preparation of BT ceramics with uniform grain because of their ultra-small size. At a sintering temperature of 1220 °C, the dielectric constant of BT ceramics at the Curie temperature is 8661. This dielectric constant value is higher than that reported for BT ceramics in most literature, and even higher than some doped modified BT ceramics. The solvothermal-calcination method used for preparing Ultra-BT provides important reference value for the preparation of other ultra-small perovskite materials. At the same time, because of the excellent dielectric properties and good catalytic properties of Ultra-BT, it has potential application value in the field of dielectric and catalysis.