Formation of single-crystalline BaTiO3 nanorods from glycolate by tuning the supersaturation conditions

• Published in: Ceramics international 2022-05, Vol.48 (9), p.11988-11997
• Main Authors: Kovalenko, O., Škapin, S.D., Maček Kržmanc, M., Vengust, D., Spreitzer, M., Kutnjak, Z., Ragulya, A.
• Format: Article
• Language: English
• Subjects: Barium titanate (D); Crystallization mechanism (A); Hydrothermal synthesis (A); Perovskite (D); Rod-shaped nanoparticle (B); Supersaturation (C)
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2022.01.048

We have studied peculiarities in the formation of single-crystalline barium titanate (BaTiO3) nanorods from a glycolate-mediated complex via a single-step hydrothermal process under different supersaturation (SR) conditions. X-ray diffraction (XRD) showed the formation of pure BaTiO3 with an SR of above 19. The tetragonality for the BaTiO3 (c/a) reached 1.013 at SR = 19–29 and dropped to 1.010 for SR = 39. According to the transmission electron microscopy (TEM) and XRD analyses, the rod-shaped particles exhibited single crystallinity and crystal growth along the [001] plane. With scanning electron microscopy (SEM), the morphological evolution from a plate-shaped intermediate precursor (SR = 6–9) to a rod-shaped product with an aspect ratio of 6–9 (SR = 19–29), and to non-polar material with an irregular structure (SR = 39), was observed. The negative slope, linear dependence of the particles’ width and length on the supersaturation level in the range SR = 19–39 was established for the first time. The replacement of the prevailing crystallization mechanism from in-situ topotactic transformation into dissolution-precipitation above SR = 19 was observed. It was shown that with a simple regulation of the SR, the structural and morphological characteristics of the obtained BaTiO3 nanoparticle can be effectively tuned.