Structural, electrical and optical properties of (K,Ba)(Nb,Ni)O3–δ electroceramics: Oxygen vacancy and grain size effects

Physical characterization of BiFeO3‐based thin films with enhanced properties for photovoltaic applications

“…It has been recently reported that for perovskite-type materials, the main contribution to the broadening of the XRD peak profiles, which are related to the intrinsic microstrain and are well known to be affected by the structural defects, directly related to the vacancies and interstitial cations. 26,37,38 Therefore, the observed anomaly in the lattice microstrain for the BLFO-20 composition seems to be in agreement with the obtained results from the XRD properties, suggesting that the lanthanum cation could be partially entering the B site of the perovskite structure for concentrations higher than x = 15 mol%, thus providing evidence for the amphoteric behavior of the doping element. Hence, the inclusion of the lanthanum content into the B site leads to additional structural defects caused by the cationic competition between different ionic radius elements (La and Fe), thus promoting an increase in the lattice microstrain for the highest lanthanum concentration thin film.…”

“…A similar trend to that observed for the unit cell volume was also obtained for ε , which decreases as the lanthanum content increases up to the BLFO–15 composition, and then increases for the BLFO–20 film. It has been recently reported that for perovskite‐type materials, the main contribution to the broadening of the XRD peak profiles, which are related to the intrinsic microstrain and are well known to be affected by the structural defects, directly related to the vacancies and interstitial cations 26,37,38 . Therefore, the observed anomaly in the lattice microstrain for the BLFO–20 composition seems to be in agreement with the obtained results from the XRD properties, suggesting that the lanthanum cation could be partially entering the B site of the perovskite structure for concentrations higher than x = 15 mol%, thus providing evidence for the amphoteric behavior of the doping element.…”

“…Detailed information about the optical characterizations can be found elsewhere. 26 The samples are hereafter labeled as BFO, BLFO-10, BLFO-15, and BLFO-20, for x = 0, 10, 15, and 20 mol% La, respectively. patterns has been carried out from the Rietveld method, using the Fullprof Suite Package software, 27 and the results are shown in Figure 1.…”

“…Absorbance spectra have been obtained using the integrating sphere (IS) method, from diffuse reflectance and collimated transmittance collected data. Detailed information about the optical characterizations can be found elsewhere 26 . The samples are hereafter labeled as BFO, BLFO–10, BLFO–15, and BLFO–20, for x = 0, 10, 15, and 20 mol% La, respectively.…”

Study of the dielectric relaxation mechanisms in KNbO3-based electro-ceramics

“…Next, the mixed oxides were ball-milled again, dried, and then isostatically pressed at 150 MPa. Finally, the samples were sintered in an air atmosphere at 1150 o C for 2h [9]. Figure 1 depicts a schematic diagram showing the steps for the samples' preparation.…”