Local structure and ionic transport in acceptor-doped layered perovskite BaLa₂In₂O₇

Abstract

Materials with perovskite or perovskite-related structure have many applications because of theirs different physical and chemical properties. These applications are extremely diverse and cover different fields including hydrogen energy. Layered perovskites with Ruddlesden-Popper structure constitute a novel class of ionic conductors. In this paper, the effect of acceptor doping on the local structure and its relationship with transport properties were shown for layered perovskites based on BaLa2In2O7 for the first time. The geometric factor (the increase in the unit cell volume due to the increase in the ionic radii of cations) plays major role in the area of small dopant concentration (x 0.15). The concentration factor (the increase in the oxygen vacancy concentration) is more significant in the area of big dopant concentration (x 0.15). The acceptor doping is a promising way of improving the oxygen-ionic conductivity of layered perovskite BaLa2In2O7.

Novel Protonic Conductor SrLa2Sc2O7 with Layered Structure for Electrochemical Devices

“…Local structure of the SrLa2Sc2O7 composition was investigated u spectroscopy method. Figure 2 The low-wavenumbers region (120−200 cm −1 ) contains several signa to the stretching and bending vibrations of alkali-earth-and rare-earth-c polyhedra [51,[56][57][58][59] (Table 2). The tilting/bending and stretching vibra The low-wavenumbers region (120−200 cm −1 ) contains several signals corresponded to the stretching and bending vibrations of alkali-earth-and rare-earth-containing metal polyhedra [51,[56][57][58][59] (Table 2).…”

“…Figure 2 The low-wavenumbers region (120−200 cm −1 ) contains several signa to the stretching and bending vibrations of alkali-earth-and rare-earth-c polyhedra [51,[56][57][58][59] (Table 2). The tilting/bending and stretching vibra The low-wavenumbers region (120−200 cm −1 ) contains several signals corresponded to the stretching and bending vibrations of alkali-earth-and rare-earth-containing metal polyhedra [51,[56][57][58][59] (Table 2). The tilting/bending and stretching vibrations of trivalent metal with small ionic radii polyhedra (scandium, in our case [60]) should be located in the mid-and high-wavenumbers region (higher 200 cm −1 ).…”

“…Such matrix compositions as BaNdInO 4 [31][32][33][34][35], BaNdScO 4 [36], SrLaInO 4 [37][38][39][40][41], BaLaInO 4 [42][43][44][45][46][47] and compounds based on them were investigated, and general regularities of proton transport in doped monolayer perovskites were revealed [48]. Two-layer perovskites with the general formula AA' 2 B 2 O 7 (n = 2), such as BaLa 2 In 2 O 7 [49][50][51][52] and BaNd 2 In 2 O 7 [53],…”

Synthesis, Hydration Processes and Ionic Conductivity of Novel Gadolinium-Doped Ceramic Materials Based on Layered Perovskite BaLa2In2O7 for Electrochemical Purposes

“…The two-layer composition BaLa 2 In 2 O 7 of this homologous series AA' n B n O 3n+1 was also described as a protonic conductor [47]. The possibility of water uptake was proved, and the use of the acceptor-doping strategy made it possible to significantly increase the proton conductivity [48][49][50]. However, the isovalent-doping strategy for the modification of the structure and transportation properties has not been applied to the two-layer perovskite BaLa 2 In 2 O 7 yet.…”