Convectional hydrothermal synthesis of high-purity pesudo-cubic BaTi0.09Nb0.01O3 nanocrystals in rotary autoclave

Document Type : Reasearch Paper


Department of Metallurgical and Materials Engineering, Iran University of Science and Technology (IUST), Narmak, Tehran, Iran.



Nano-sized BaTiO3 powders with particular Nb concentrations were prepared by Rotary- Hydrothermal (RH) method. Hydrothermal method was used at 180 °C for 5 hours with new Ti pressure and the teflon vessel was rotated at a speed of 160 rpm during the hydrothermal reaction. New hydrothermal method was used instead of previous solid state reaction for the system BaTiO3±Nb2O3 in high temperature to achieve nano sized particles in lower time and temperature. Synthesis with Rotary-hydrothermal has the advantages of faster crystallization, decreased crystal size, more homogenous distribution of dopants at lower temperature and time in comparison with the solid state method. In case of the phase evolution studies the X-ray diffraction patterns (XRD) measurements and Raman spectroscopy were performed. The Transmission Electron Microscope (TEM) and the Field Emission Scanning Electron Microscopy (FE-SEM) images were taken for the detailed analysis of the grain size, surface and morphology. Synthesis of Nb doped BaTiO3 with the Rotary- hydrothermal provided advantages of fast crystallization and decreased crystal size.


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