Structural properties and the influence of d electrons' insertion in PbTiO(3) have been determined in the study of PbM(1-x)M(x)'O(3) (M, M' = Ti, Cr, and V) solid solutions by means of X-ray diffraction, high-resolution transmission electron microscopy, magnetization measurements, and strain mapping analysis. PbTi(1-x)V(x)O(3) is the only system that preserves the same space group (P4mm) for all x, whereas PbTi(1-x)Cr(x)O(3) and PbV(1-x)Cr(x)O(3) change to cubic (Pm ̅3m) at x = 0.30 and 0.4, respectively. These values have been related with the percolation threshold for a cubic net (P(c) = 0.31). The microscopy study coincides with the X-ray diffraction determination, and neither supercell nor short-range order maxima are observed. However, for x ≥ 0.7 in PbTi(1-x)Cr(x)O(3) the presence of modulated zones is observed in both the electron diffraction pattern as well as high-resolution transmission electron micrographs, as is typical for PbCrO(3). (1) Furthermore, the tetragonal region in PbV(1-x)Cr(x)O(3) suffers a great stress because of the contrast of [Cr-O(6)] octahedra and [V-O(5)] square-based pyramids end members basic units.
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J Am Chem Soc
January 2025
Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, Grenoble INP, LEPMI 38000 Grenoble, France.
An original approach to characterize electrochemical interfaces at the atomic level, a challenging topic toward the understanding of electrochemical reactivity, is reported. We employed surface resonant X-ray diffraction experiments combined with their simulation using first-principle density functional theory calculations and were thus able to determine the molecular and electronic structures of the partially ionic layer facing the electrode surface, as well as the charge distribution in the surface metal layers. Pt(111) in an acidic medium at an applied potential excluding specific adsorption was studied.
View Article and Find Full Text PDFRSC Adv
January 2025
Centre for Nano Bio Polymer Science and Technology, Department of Physics, St. Thomas College Palai Kerala 686574 India +919446126926.
We report a green approach to prepare carbon dots (CDs) with fresh tomatoes as carbon sources and amino acids as dopants (ACDs) by a microwave assisted method. The synthesised CDs were analysed by UV-visible absorption spectroscopy, photoluminescence spectroscopy, high resolution transmission electron spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photo electron spectroscopy. An MTT assay was used to evaluate the cytotoxicity of CDs toward L929 cells and found that CDs exhibit low cytotoxicity.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Physics, Facility of Science, King Abdulaziz University, Jeddah, Saudi Arabia.
The influence of variations in indium concentration and temperature on threshold current density (J) in In Ga As/GaAs ( = 0, 0.8 and 0.16) quantum dot (QD) laser diodes - synthesized via molecular beam epitaxy (MBE) with three distinct indium concentrations on GaAs (001) substrates - was meticulously examined.
View Article and Find Full Text PDFHeliyon
January 2025
Nuclear Chemistry Division, Department of Chemistry, Atomic Energy Commission, P. O. Box: 9061, Damascus, Syrian Arab Republic.
Molecular scale information is needed to understand ions coordination to mineral surfaces and consequently to accelerate the design of improved adsorbents. The present work reports on the use of two-dimensional correlation Fourier Transform infra-red spectroscopy (2D-COS-FTIR) and hetero 2D-COS-FTIR- X-ray diffraction (XRD) to probe the mechanism of Cr(VI) removal from aqueous solutions by activated carbon (AC) and its composite with PWO (AC-composite). The adsorption data at an initial Cr(VI) concentration of 320 mg L (320 ppm) revealed maximum adsorption capacities of 65 mg g for AC and 73 mg g for AC-composite, corresponding to removal percentages of 83 % and 94 %, respectively.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia.
This study aims to investigate the crystallographic properties of hydroxyapatite (HAp) and strontium-substituted hydroxyapatite (SrHAp) obtained from sand lobster shells (SLS) using various analytical methods. HAp and SrHAp were synthesized by the hydrothermal method using sand lobster () shell waste as a calcium precursor. SLS were calcined at 0 °C, 600 °C, 800 °C, and 1000 °C and characterized by X-ray diffraction (XRD).
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