Zinc titanates nanopowders: synthesis and characterization

Abstract

Zinc titanates nanopowders viz.; Zn2TiO4, ZnTi3O8 and ZnTiO3 were synthesized through the thermal decomposition course of ZnC2O4.2H2O-TiO2 precursors mixture (1:1 mole ratio), prepared via a new co-precipitation method up to 900°C. Thermogravimetric measurement (TG) was utilized to characterize the precursors mixture decomposition while X-ray diffraction (XRD), Fourier transform infra-red (FT-IR) were used to characterize the decomposition products as well as the phase transitions at different temperatures. XRD revealed the starting of titanates formation at 700°C via detecting Zn2TiO4 along with ZnO and TiO2 (anatase) diffraction peaks. By increasing the calcination temperature to 800°C, the ZnO content vanished with the appearing of Zn2Ti3O8 besides ZnTi2O4 and impurities of TiO2 (anatase). Finally at 900°C, the Zn2Ti3O8 content was decomposed into ZnTiO3. Nitrogen adsorption-desorption isotherm of the calcined precursors mixture at 900°C indicated low specific surface area of 7.1 m2 g-1 in accordance with the agglomeration nature estimated via transmission electron microscopy (TEM) study. The conductivity measurements showed semiconducting behavior of the prepared titanates with ferroelectric transition in the range 200-308°C.The obtained low dielectric value suggests the uses of present titanates as a co-fired ceramic or resonator ceramics.

Faujasite-Type Zeolite Obtained from Ecuadorian Clay as a Support of ZnTiO3/TiO2 NPs for Cyanide Removal in Aqueous Solutions

“…This oxide has a bandgap energy similar to that of TiO 2 (3.2 eV for TiO 2 and 3.4 eV for ZnO) [18]. Zinc titanate, also known as zinc titanium oxide, is an inorganic compound that exists in three main forms: ZnTiO 3 (ZnO-TiO 2 ), Zn 2 TiO 4 (2ZnO-TiO 2 ), and Zn 2 Ti 3 O 8 (2ZnO-3TiO 2 ) [20]. ZnTiO 3 has a perovskite crystal structure, which consists of a three-dimensional network of corner-sharing oxygen octahedra.…”

“…In the solid-state method, stoichiometric amounts of ZnO and TiO 2 are mixed and heated at high temperatures. The sol-gel method involves the formation of a precursor solution, followed by gelation, drying, and calcination [20]. ZnTiO 3 exhibits a wide bandgap, typically around 3-3.5 eV [22].…”