Temperature dependence of the concentration of surface phases in a BaTiO3 single crystal according to X-ray photoelectron spectroscopy data

Effect of sintering temperature on the chemical state of ions in the Ba1 − x Sr x TiO3 (x = 0.2) system, according to X-ray photoelectron spectroscopy data

“…This spread exceeds the accuracy of experimental determination for the binding energy (~0.1-0.2 eV) even with allow ance for charging effects. However, this energy is close to the binding energy of the Ba4d 5/2 level in BaTiO 3 sin gle crystals [5]. We therefore associate this component with the Ba 3+ ions in BST.…”

“…Table 2 shows that this was indeed the case. These components have a notable temperature dependence on the same surface of a BaTiO 3 single crystal [5]. However, their emergence on the surfaces of different BST samples prepared at different temperatures has no other physical meaning than the one described above.…”

“…The origin of this component in the Ba4d X ray photoelectron spec tra of BaTiO 3 single crystals has been studied by a num ber of authors [6,7]. We reported the results of similar studies in [5]. When the surface of a BaTiO 3 single crystal is con ditioned mechanically with a diamond needle file, both a single plane containing barium and oxygen ions at the depths of XPS analysis and a number of such planes lying one below the other can be found in dif ferent regions of the surface.…”