Tuning shape of barium titanate nanocubes by combination of oleic acid/tert-butylamine through hydrothermal process

Abstract

The shape and surface morphology of mono-dispersed barium titanate (BaTiO3) nanocrystals were controlled by tuning the composition of hydrothermal reaction system. High quality BaTiO3 nanocubes with the smooth surface and 90° standard corner angle were synthesized by the hydrothermal method using a relatively low concentration of oleic acid and tert-butylamine, which were used as surfactant and additive, respectively. The average size of BaTiO3 nanocubes was ∼25 nm and the size distribution was relatively narrow. As a large amount of surfactant and additive was employed, BaTiO3 nanocrystals with convex structure were synthesized. The terrace structure were developed at the {100} surface of the nanocrystals. Here, we analyzed systematically the role of oleic acid and tert-butylamine on the surface morphology of BaTiO3 nanocrystals. Our study demonstrates the possibility of synthesizing high quality BaTiO3 nanocubes for commercial application. These findings can be applied on other perovoskite nanomaterials.