Facile Synthesis of BaTiO₃ Nanocubes with the Use of Anatase TiO₂ Nanorods as a Precursor to Titanium Hydroxide

Abstract

We report a solvothermal method for the facile and reproducible synthesis of BaTiO3 nanocubes by employing anatase TiO2 nanorods as a precursor to titanium hydroxide. The TiO2 nanorods were, in turn, synthesized in advance through another solvothermal process. We could obtain high‐quality BaTiO3 nanocubes by reacting the TiO2 nanorods with Ba(NO3)2 under solvothermal conditions in the presence of oleic acid and acetic acid as dual capping agents, followed by a purification process involving chemical washing and physical filtration. The addition of acetic acid alongside oleic acid was critical to the formation of well‐defined {100} facets on the nanocrystals and also increased batch‐to‐batch reproducibility without the use of a glove box or similar air‐free experimental design. Using this method, BaTiO3 nanocubes crystallized in the cubic phase could be readily obtained with an average edge length around 8 nm.