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

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 (S-R) conditions. X-ray diffraction (XRD) showed the formation of pure BaTiO3 with an S-R of above 19. The tetragonality for the BaTiO3 (c/a) reached 1.013 at S-R = 19-29 and dropped to 1.010 for S-R = 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 (S-R = 6-9) to a rod-shaped product with an aspect ratio of 6-9 (S-R = 19-29), and to non-polar material with an irregular structure (S-R = 39), was observed. The negative slope, linear dependence of the particles' width and length on the supersaturation level in the range S-R = 19-39 was established for the first time. The replacement of the prevailing crystallization mechanism from in-situ topotactic transformation into dissolution-precipitation above S-R = 19 was observed. It was shown that with a simple regulation of the S-R, the structural and morphological characteristics of the obtained BaTiO3 nanoparticle can be effectively tuned.

Automated summary

This study investigates the peculiarities in the formation of single-crystalline barium titanate nanorods through a single-step hydrothermal process using a glycolate-mediated complex. The research shows that the structural and morphological characteristics of the BaTiO3 nanoparticles can be effectively tuned by regulating the supersaturation level.