General Approach to Well-Defined Perovskite MTiO₃ (M = Ba, Sr, Ca, and Mg) Nanostructures

Abstract

Well-defined perovskite MTiO3 (M = Ba, Sr, Ca and Mg) nanostructures were successfully synthesized by a convenient hydrothermal method, employing MCl2 as M source and titanate nanowire as Ti precursor. Different perovskite nanostructures such as nanoring, nanobowl, nanotube, and nanodisk were successfully prepared. Two types of growth mechanisms were proposed by investigating the formation processes of MTiO3 nanostructures. The formation of MTiO3 (M = Ba and Sr) undergoes a “nanowire−tube−ring” growth mechanism with a self-sacrifice of titanate nanowire framework rout, whereas the formation of CaTiO3 and MgTiO3 structures follows a simultaneous epitaxial growth of TiO2 nanotube on titanate nanowire and self-nucleation of MTiO3 (M = Mg and Ca) in the solution initially, and then a conversion of the nanowire and nanotube to MgTiO3/CaTiO3 nanostructure process. The electrical properties of the perovskite MTiO3 nanostructure including polarization-field hysteresis and capacitance−voltage characteristics were also investigated.