“…The peaks at 457.9 and 463.71 eV, which correspond to Ti 4+ , are attributed to Ti 2p 3/2 and Ti 2p 1/2 , respectively. 37 The Ba 3d level consists of two peaks, Ba 3d 3/2 and Ba 3d 5/2 , with binding energies of 794.81 and 779.45 eV, respectively, and a peak difference of 15.36 eV, indicating that both barium atoms are in the Ba 2+ state. 38 It has been observed that the oxygen-deficient area is associated to the peak for O 1s spectra between 529.38 and 532.24 eV.…”