Analysis of phase transition behavior of BaCeO3 with thermal analyses and high temperature X-ray diffraction

Effect of ytterbium doping on the microstructure and plastic deformation of BaCeO3 perovskite oxide

“…Only the peaks for BaCeO 3 could be detected in the three materials. The crystal structure of barium cerate has previously been described as orthorhombic with space group Pnma (standard setting), cubic with space group Pm 3m and tetragonal with space group P42nm [14,15]. The present XRD data match correctly with the three crystal systems.…”

“…Many studies have focused on the simple ABO 3 perovskites (where A 2+ and B 4+ denote site cations), particularly cerates and zirconates, due to their high proton conducting performance when doping with trivalent cations (such as Y 3+ , Yb 3+ , Nd 3+ and Gd 3+ ) [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]. The ideal ABO 3 perovskite structure is built upon a framework of corner-linked BO 6 octahedra with the B 4+ cation placed in the center of each octahedron (6-coordinate site), and the A 2+ cation in the center of the cube formed by the octahedra (12-coordinate site); the orthorhombic phase can be regarded as a distortion of the ideal cubic configuration by octahedral tilting.…”

“…Most of the studies have focused on the processing, defect chemistry and electrical behavior of doped barium cerates [6][7][8][9][10][11][12][13][14][15][16][17][18]. Reports on the microstructural evolution with doping are, however, very limited [9][10][11][12].…”

STRUCTURAL, DIELECTRIC AND A.C. CONDUCTIVITY STUDIES OF BaCe0.65 Zr0.2Y0.15O3-δ SOLID OXIDE FUEL CELL ELECTROLYTE BY CITRATE EDTA COMPLEXING SOL-GEL PROCESS.

“…22-0074). The XRD patterns of powders calcined at T=1000°C for 12h showed a single orthorhombic phase with pnma space group according to Knight et al [17][18][19][20][21]. The cell parameters of both calcined and sintered were determined by least-square refinements and the calculated lattice parameters are found to be a=8.67145, b=6.148, c=6.236 and cell volume is 332.490(Å) 3 with a relative density of 90% which are consistent with that available in the literature [31].The lattice volumes of both the samples reflected the same trend except an increase in the lattice volume which may be due to increase in the thermal reduction of Ce 4+ to Ce 3+ [22].…”

“…In order to produce the single phase ceramic powders, the decomposition process of the gel should be controlled to suppress the formation of carbonates of constituent species, since those carbonates give possible segregation and in homogeneity in the final oxide powders. The peak localized in the range of 1450-1470cm -1 attributed to the C-H bend and which may be due to the complex formed from a chelating process of chelating agents and metal ions [17,21]. The transmittance bands around 1638.98 and 1744.5cm -1 may be due to -C=C -and C=O stretch respectively.…”