Hydrothermal Synthesis of Alkali Tantalate Nanocubes

A set of experiments was conducted to synthesize alkali tantalates in energy efficient hydrothermal process. Lithium, sodium, and potassium tantalum oxide nanocubes were synthesized at $140^{o}C$ for 15 hours in rich alkaline atmoshphere. The final products were obtained as a perovskite phase of sodium tantalate, and a defect phase pyrochlore of potassium tantalum oxide and a lithium tantalum oxide. The size of nanocubes were 25 nm, 90nm, and 50 nm for lithium tantalum oxide, sodium tantalate, and potassium tantalum oxide nanocubes, respectively. The morphological, compositional, structural, thermal, and photophysical properties of as-synthesized nanocubes were characterized using scanning electron microscope (SEM), x-ray powder diffraction (XRD), thermal gravimetric analysis (TGA) techniques, and UV Spectrometer.