Sol-gel synthesis is a wet-chemical route to oxide materials in which molecular precursors in solution are hydrolyzed and condensed into a colloidal "sol," which is then aged, dried to a "gel" or dry sol, and heat-treated (calcined) to crystallize the final oxide powder.
Use in the BSCT dossier
Patent CN119430910 — Piezoelectric Ceramic Powder for Whitening and Mineralizing Teeth prepares BSCT (Ba₀.₉Sr₀.₀₅Ca₀.₀₅TiO₃) by a sol-gel route. The precursor system is:
- A-site acetates: barium acetate (99%), calcium acetate (99%), strontium acetate (98%), dissolved in acetic acid at the molar ratio (1-2x):x:x.
- B-site alkoxide: tetrabutyl titanate, dissolved in 1 mL acetylacetone and 9 mL ethylene glycol methyl ether.
The two solutions are mixed, stirred for 5 h, aged 24–96 h, dried at 90–150 °C to a dry sol, and calcined at 600–1200 °C (5 °C/min) for 2 h.
Preferred embodiment: x = 0.05, 70 °C stirring, 72 h aging, 120 °C drying, 900 °C calcination.
Why the route matters here
The sol-gel route is what allows the barium, strontium and calcium to be mixed at the molecular scale before crystallization, which is the usual rationale for using it to make doped multicomponent oxides such as BSCT. The dossier does not compare the sol-gel product against powders made by the solid-phase or alkaline routes named in the related patent list (e.g. CN116534893, CN120965307), so no claim is made here about which route is superior.
Related
- Barium Titanate (BaTiO₃) — the parent oxide.
- BSCT (Ba₀.₉Sr₀.₀₅Ca₀.₀₅TiO₃) — the material produced.
Source notes & attribution
- https://rexresearch.com/XingBaTiCaToothpaste/XingSrCaBaTiO3Toothpaste.html