Solid phase preparation of submicron-sized SrTiO_3 crystallites from SrO_2 nanoparticles and TiO_2 powders

摘要

Submicron-sized SrTiO_3 crystallites were prepared by a low temperature solid state method. The proposed preparation method involved two simple steps: firstly, SrO_2 nanoparticles of 35-90 nm were precipitated from the reaction of Sr(NO_3)_2 and H_2O_2 in an alkalescent aqueous solution (pH=8) under the ambient condition; secondly, perovskite phase SrTiO_3 with a minor amount of SrCO_3 impurity were produced by heating the mixture of excessive SrO_2 nanoparticles and commercial TiO_2 powders in air at 700 ℃ for 10 h, which could be easily washed with 1 mol/l HNO_3 aqueous solution and distilled water to yield pure SrTiO_3 crystallites with the size of about 125-320 nm. The phase, purity and size of the as-obtained product were characterized by means of powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy (FESEM).