One-step synthesis of BaTiO3/CaTiO3 core-shell nanocubes by hydrothermal reaction

Abstract

Novel cube-shaped nanocrystals of BaTiO3 (BT) surrounded by CaTiO3 (CT) that can be used for piezo-driven energy harvesters were synthesized using a one-step hydrothermal reaction with surfactant and additives at 250°C for 24 h. The size distribution of the nanocubes (NCs) was narrow, with an approximate average size of 50 ~ 60 nm. The nanocubes had a core-shell configuration, such that the Pbnm structured CT shell was grown on a P4mm structured BT core by sharing corresponding [001] directions. STEM-EDX and EELS indicated that Ba ions did not diffuse into the CT shell region. Piezoelectric hysteresis loops of BT/CT NCs were obtained by piezoresponse force microscopy.

Keywords

• hydrothermal synthesis
• nanocube
• core-shell structure
• heterointerfaces
• piezoelectrics