Study of the hydrothermal crystallization process of barium titanate by means of X-ray mass attenuation coefficient measurements at an energy of 59.54 keV.

In this work, the X-ray mass attenuation coefficients of hydrothermally synthesized barium titanate (BaTiO 3 ) samples were calculated with the purpose of determining the crystallization sequence of BaTiO 3 . Hydrothermally synthesized samples prepared at 100 °C and 200 °C, and reacted for varying reaction times between 15 min up to 120 h were studied. Attenuation coefficient measurements were done with a coaxial HPGe gamma detector (Ortec, GEM55P4-95) with a working range in the X-ray energy region. The samples were made into pellets and were exposed to 241 Am radioisotopes at an energy of 59.54 keV for 300 s. Additionally, FT-Raman and XRD measurements were done to support the X-ray mass attenuation measurements. It was found that secondary barium titanate (BT) phases (BaTi 2 O 5 and Ba 2 TiO 4 ) were formed from the precursor material at the early stages of the hydrothermal reaction and that phase pure BaTiO 3 was formed at longer reaction times. The sequence of barium titanate crystallization was determined as follows: BaTi 2 O 5 ; BaTi 2 O 5 and BaTiO 3 ; BaTi 2 O 5 , Ba 2 TiO 4 and BaTiO 3 : and phase pure BaTiO 3 . [ABSTRACT FROM AUTHOR]