Low-Temperature Synthesis of La2Ti2O7 Nanocrystal by Metallorganic Decomposition Method

Abstract

Nanopowders of La2Ti2O7 have been successfully prepared by metallorganic decomposition method (MOD). In comparison with the higher reaction temperature of conventional preparation methods, such as solid-state reaction (about 1100°C), the nanocrystal La2Ti2O7 phase can be formed at an evidently lower temperature of 700°C by MOD. The resulting powders exhibit small and uniform grains. The imagines of FT-IR show that acetylacetone can associate with La3+ to form La-acetylacetone chelate complexes, and the absorption peak of La3+ in precursor solution disappears, while the peaks of chelate complexes located at 1580 and 1420 cm-1 are found correspondingly. The probable reason is that small precursor particles can be formed at a homogeneous and low La3+ concentration by control release from the complexes; these small, uniform and more active precursor particles probably make it possible to form La2Ti2O7 nanocrystal at significantly lower preparation temperature.