Fig. 1
Schematic detailing the synthesis of nanocrystalline BST powder.
Fig. 2
FT-IR spectra of the xerogel.
Fig. 3
FT-IR spectra of BST powder calcined at 750 and 850 °C.
Fig. 4
XRD patterns of the BST powders synthesized at 600, 750, 850 °C. The peaks associated with the barium carbonate secondary phases are marked with asterisks.
Table 1
The Crystallographic parameters used for the XRD pattern fitting for BST60/40 ceramics (PDF Card No. 00-034-0411).
| Crystal system | Cubic | Angles (α, β, γ) | 90.00°, 90.00°, 90.00° |
| Space group number | 221 | Calculated density | 5.68 |
| Space group | Pm-3m | Volume of cell | 62.33 |
| Lattice parameter s | 3.965 Å, 3.965 Å, 3.965 Å |
Table 2
Details of the calculated X-ray spectrum for BST powder calcined at 750 °C.
| h k l | 2θ [deg] | dhkl [Å] | FWHM [deg] | Crystal size [nm] | Lattice parameter [Å] |
|---|---|---|---|---|---|
| 1 0 0 | 22.265 | 3.9893 | 0.1993 | 40.61 | |
| 1 1 0 | 31.827 | 2.8092 | 0.2423 | 34.08 | |
| 1 1 1 | 39.368 | 2.2867 | 0.2709 | 31.13 | |
| 2 0 0 | 45.724 | 1.9826 | 0.3145 | 27.40 | |
| Average | 33.31 | ||||
| 3 1 0 | 75.897 | 1.2525 | 3.959 | ||
| 3 1 1 | 80.035 | 1.1979 | 3.971 | ||
| 2 2 2 | 84.608 | 1.1444 | 3.963 | ||
| Average | 3.965 |
Table 3
Details of the calculated X-ray spectrum for BST powder calcined at 850 °C.
| h k l | 2 [deg] | dhkl [ Å] | FWHM [deg] | Crystal size [nm] | Lattice parameter [ Å] |
|---|---|---|---|---|---|
| 1 0 0 | 22.279 | 3.9869 | 0.1665 | 48.61 | |
| 1 1 0 | 31.826 | 2.8093 | 0.2193 | 37.65 | |
| 1 1 1 | 39.312 | 2.2899 | 0.253 | 33.33 | |
| 2 0 0 | 45.632 | 1.9864 | 0.2748 | 31.35 | |
| Average | 37.74 | ||||
| 3 1 0 | 75.609 | 1.2566 | 3.972 | ||
| 3 1 1 | 80.281 | 1.1948 | 3.961 | ||
| 2 2 2 | 84.378 | 1.1469 | 3.972 | ||
| Average | 3.969 |
Fig. 5
The FESEM micrograph of BST (a) calcined at 750 °C for 2 h and (b) calcined at 850 °C for 4 h.
Fig. 6
The EDS pattern of the Ba0.6Sr0.4TiO3 powder synthesized at 750 °C.