he contents of silver in the BTA20 and BTA15 samples are respectively
about 14.1 mol% and 10.5 mol%. Besides, it can be seen that for pure
BaTiO3, reflection peaks of (0 0 2) and (2 0 0) obviously split. With
increasing Ag content, the split is weakened, suggesting that tetragonality of barium titanate decreases, which can be further verified
by Raman spectra