Microstructural Study of the Li+Ion Substituted Perovskites Li0.5−3xNd0.5+xTiO3

Modulated Structure of La1/3−xLi3xNbO3 0≤x≤0.06 Perovskite-Related Materials

“…7b and 7a, respectively), which under these conditions do not form a three dimensional microdomain structure with three di!erent orientations of the c-axis. This kind of microdomain formation has also been observed in the¸n \V Li V TiO (¸n"La, Nd) solid solutions (6,8,11) and seems to be correlated to the degree of orthorhombicity in materials with perovskite-related structure in a way that the amount of twinning increases when the orthorhombicity of the structure decreases (28). In the La \V Li V NbO compounds, the orthorhombicity of the basic structure decreases when the lithium content increases (14), which seems to explain the appearance of a microdomain structure with three di!erent orientations of the c-axis in the samples with high lithium contents (x"0.05 and 0.06).…”

“…3). This splitting might be due to the existence of a microdomain structure in which the system of the tilting of the octahedra around the [110] N and [1 10] N axes is twinned across intersecting (100) N and (010) N domain boundaries, as it has been observed in other A-cation de"cient perovskites (24}26) as well as in the Li \V Nd >V TiO solid solution (11). The combination of all these observations suggests for the niobate solid solution the reciprocal unit cell represented in Fig.…”

Structure, microstructure and magnetic properties of Sr1−xCaxCrO3 (0⩽x⩽1)

“…3c, only two of the splitted spots can be observed. This six-fold spot splitting could be due to some Ca/Sr exolution for this composition [22], or to ordering between Ca and Sr probably coupled to the microdomains which formed the system of octahedra tilt [23]. For x ¼ 0.8 and 1.0 compositions, the 1 2 ðhklÞ reflections become a single spot, (1/3 1/2 1/2) c , labelled as (121) o in the orthorhombic setting in Fig.…”

Study of the lithium insertion and de-insertion in perovskite praseodymium bismuth lithium titanate

“…Lanthanum has been substituted by other rare-earth elements (Pr, Nd and Sm), but the resulting conductivity is lower. [6][7][8][9][10] Substitutions in the B-site in RE 0.5+x+y Li 0.5−3x Ti 1−3y Cr 3y O 3 (RE = Pr, La and M = Mn, Cr, Sn, Zn and Ge) have been reported to increase electronic conduction without affecting ionic conduction. [11][12][13][14] Recently, the rare-earth cations were partially substituted by bismuth.…”

“…Since the A-B-sites in this structure can tolerate different ions with different valence states, several studies have been reported in various systems. [2][3][4][5][6][7][8][9] Up to now, the best lithium-ion conducting electrolytes among these oxides are the lanthanum lithium titanates La 2/3−x Li 3x TiO 3 (LLTO), with a room temperature conductivity of 10 −3 S cm −1 for La 0.51 Li 0.35 TiO 2.94 . 4,5 The compounds in this system are ionic conductors but show negligible electronic conduction.…”