Synthesis, structural refinement and physical properties of novel perovskite ceramics Ba1-xBixTi1-xMnxO3 (x = 0.3 and 0.4)

Enhanced Photocatalytic Water Splitting of SrTiO3 Perovskite through Cobalt Doping: Experimental and Theoretical DFT Understanding

“…Afterward, we performed the Rietveld refinement (described in the Supporting Information) on the X-ray diffraction data using the Full-Prof program to provide different structural parameters such as unit cell, symmetry, and atomic positions. The structural refinements were carried out with the cubic structure in the Pm 3̅ m symmetry for different concentrations of Co dopant in the Ti-site using an initial model of STO . In this model, the Sr, Ti/Co, and O atoms are placed at the 1a (0, 0, 0), 1b (1/2, 1/2, 1/2), and 3c (1/2, 1/2, 0) sites, respectively.…”

“…Using the Kubelka–Munk function, the UV–vis diffuse reflectance spectra have been transformed into absorbance spectra using the following formula: F ( R )  α S = ( 1 − R ) 2 2 R where F ( R ) denotes the Kubelka–Munk function, α is the absorption coefficient, and R is the diffuse reflectance (DR).…”

“…Based on the optical band gap energy ( E g ), the energy levels of VBM and CBM of pristine and cobalt-doped SrTiO 3 materials can be calculated via the following relations: E VBM = χ STCO − E e + 1 2 E g E CBM = E VBM − E g where E e = 4.5 eV denotes the total energy of a free electron, and χ STCO denotes the electronegativity of pure and cobalt-doped STO materials, which is calculated by the formula below: χ STCO = false[ χ Sr χ Ti 1 − x χ Co x χ O 3 false] 1 / 5 where χ S T C O represents the absolute electronegativity for each composition in the perovskite series SrTi 1– x Co x O 3−δ (0 ≤ x ≤ 0.50), and χ Sr , χ Ti , χ Co , and χ O are the electronegativities of Sr, Ti, Co, and O elements, respectively. Besides, the electronegativity values of various elements were obtained from Bartolotti …”

Competitive crystallization, in situ separation and solidification mechanism of Cr-spinel crystal from Cr-bearing slag

“…Scattered X-rays were filtered with a post-sample graphite monochromator to obtain the XRD pattern in line with the condition of the Rietveld refinement. In addition, Rietveld refinement was performed using the program Fullproof, 30,31 and the atom coordinates of FeCr 2 O 4 (ICSD 171121) were taken as the starting model to obtain the molecular formula and lattice parameters of various high-purity Cr-spinel crystals. The experimentally determined Kα 2 /Kα 1 ratio was 0.50 for monochromator polarization correction, and the detected diffraction peaks in the XRD patterns were fitted in the pseudo-Voigt profile function.…”

Impact of rare earth (RE3+ = La3+, Sm3+) substitution in the A site perovskite on the structural, and electrical properties of Ba(Zr0.9Ti0.1)O3 ceramics

“…It is obviously noticed that the cations Ti 4+ and Zr 4+ form with the oxygen anions regular (Ti/Zr)O 6 octahedra, these are not distorted due to the higher symmetry of the cubic Pm 3m space group. 9,63,64 The (Ti/Zr)O 6 octahedra are connected in three dimensions by oxygen anions. In addition, Ba 2+ and La 3+ are surrounded by 12 oxygen anions, giving (Ba/La)O 12 polyhedra.…”