Shape-controlled hydrothermal synthesis of ferroelectric Bi4Ti3O12 nanostructures

Single-crystalline Bi4Ti3O12 (BIT) nanostructures with various morphologies including nanoplates, lamellae, nanobelts and nanorods have been controllably synthesized by a facile hydrothermal process. The structure and morphology characterizations of BIT were investigated by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). The type of mineralizer and concentration play an important role on the structure and morphology of BIT products. A possible growth mechanism has been proposed by time-dependent experiments. In addition, UV-Vis absorption spectra have shown that the as-synthesized BIT samples have a slightly red-shift behavior. The piezoelectricity of BIT nanoplates and lamellae are confirmed by piezoresponse force microscopy. Local piezoresponse force measurements display a typical butterfly curve, indicating good ferroelectric property of the BIT nanoplates and lamellae.