Hydrothermal derived barium niobate ultra-fine powders and nanowires

Hydrothermal synthesis of barium niobates was investigated together with the characterization of structure, particle size and morphology by scanning electron microscope (SEM), XRD, EDS, IR spectrum and DSC/DTA. Two kinds of barium niobates, Ba5Nb4O15 and Ba4Nb2O9, with different morphology were obtained at the different pH values. Ba5Nb4O15 was formed at pH 12–13, while the product became Ba4Nb2O9 at pH ≥ 14. The Ba5Nb4O15 particles synthesized at pH 12 exhibited the platelet morphologies, and the nanowires of Ba5Nb4O15 were obtained at pH 13. Hydrothermal derived Ba4Nb2O9 ultra-fine powders had the platelet morphology. The synthesis of ultra-fine powders and nanowires provided the great opportunity in optimizing the microwave dielectric characteristics by controlling microstructures of barium niobates ceramics.