Low-temperature preparation of nanoplated bismuth titanate microspheres by a sol–gel-hydrothermal method

Abstract

A layered inorganic perovskite micrometer-scale material, nanoplated bismuth titanate (Bi 4Ti 3O 12) microspheres (NBTMs) constructed with tens of Bi 4Ti 3O 12 nanoplates, was for the first time synthesized by a novel sol–gel-hydrothermal route. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy. The results indicated that the NBTMs possessed an average diameter of about 1.0 μm while its comprising nanoplates had the thickness and side length of about 15 and 200 nm respectively, and the processing temperature was as low as 180 °C, which is comparatively lower than that synthesized by the normal sol–gel route. It is believed that the gel precursor and hydrothermal environment play an important role in the formation of NBTMs at a low temperature. Due to the good sinterability of NBTMs, the ferroelectric and dielectric properties of Bi 4Ti 3O 12 ceramics prepared by sol–gel-hydrothermal route were super to that prepared by sol–gel route.