Template-free hydrothermal synthesis of single-crystalline barium titanate and strontium titanate nanowires

A template-free, hydrothermal synthesis of single-crystalline BaTiO 3 and SrTiO3 1D nanowires, was investigated. The synthesis involved low-cost, all-inorganic raw materials, unlike other sol-gel or hydrothermal synthesis. The operations were carried out in a glovebox filled with nitrogen in the absence of moisture of CO2. Equimolar Ba(OH)2 and TiO2 particles were mixed together using a mortar and pestle. The mixture was transferred to a Teflon-coated reactor containing water and liquid ammonia was added to adjust the pH above 13. The reactor was put into hydrothermal reaction at a constant temperature of 170°C without disturtbance for three days. The as-synthesized white precipitate was washed with water and dried in an oven at 60°C. X-ray diffraction (XRD) patterns showed the nanowires were composed of highly crystalline, cubic pervoskite structure of BaTiO3 and SrTiO 3.