| 1. |
- Afroze, Shammya, 1987, et al.
(författare)
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Insight of novel layered perovskite PrSrMn2O5+δ: A neutron powder diffraction study
- 2020
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Ingår i: Materials Letters. - : Elsevier BV. - 1873-4979 .- 0167-577X. ; 261
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Tidskriftsartikel (refereegranskat)abstract
- Neutron diffraction is very important to characterizing complex oxide materials, especially for the light element position and occupancy. In this study, a new layered perovskite oxide material, PrSrMn2O5+δ, was prepared by the solid-state reaction method and characterized by using X-ray and neutron powder diffraction, scanning electron microscopy and thermogravimetric analysis. X-ray diffraction data showed that the material adopted orthorhombic symmetry and Rietveld refinement of the neutron diffraction data gave accurate unit cell parameters (a = 3.8907 (1) Å, b = 3.8227 (1) Å, and c = 7.6846 (2) Å, atomic positions and space group (Pmmm)). Scanning electron microscopy showed a porous and interlinked microstructure. Thermogravimetric analysis exhibited two-stage weight losses up to 1000 °C from room temperature, indicating a good amount of oxygen losses and high material stability.
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| 2. |
- Afroze, Shammya, 1987, et al.
(författare)
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Investigation of structural and thermal evolution in novel layered perovskite NdSrMn 2 O 5 + δ via neutron powder diffraction and thermogravimetric analysis
- 2020
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Ingår i: International Journal of Chemical Engineering. - : Hindawi Limited. - 1687-806X .- 1687-8078. ; 2020
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Tidskriftsartikel (refereegranskat)abstract
- Neutron diffraction is one of the best methods for structural analysis of a complex, layered perovskite material with low symmetry by accurately detecting the oxygen positions through octahedral tilting. In this research, the crystal structure of NdSrMn2O5+δ was identified through X-ray diffraction (XRD) and neutron powder diffraction (NPD) at room temperature (RT), which indicated the formation of a layered structure in orthorhombic symmetry in the Pmmm (no. 47) space group. Rietveld refinement of the neutron diffraction data has confirmed the orthorhombic symmetry with unit cell parameters (a = 3.8367 (1) Å, b = 3.8643 (2) Å, and c = 7.7126 (1) Å), atomic positions, and oxygen occupancy. Thermogravimetric analysis revealed the total weight loss of about 0.10% for 20–950°C temperature, which occurred mainly to create oxygen vacancies at high temperatures. Rietveld analyses concurred with the XRD and neutron data allowing correlation of occupancy factors of the oxygen sites.
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| 3. |
- Afroze, Shammya, et al.
(författare)
-
Investigation of Structural and Thermal Evolution in Novel Layered Perovskite NdSrMn2O5+δ via Neutron Powder Diffraction and Thermogravimetric Analysis
- 2020
-
Ingår i: International Journal of Chemical Engineering. - : Hindawi Limited. - 1687-806X .- 1687-8078. ; 2020
-
Tidskriftsartikel (refereegranskat)abstract
- Neutron diffraction is one of the best methods for structural analysis of a complex, layered perovskite material with low symmetry by accurately detecting the oxygen positions through octahedral tilting. In this research, the crystal structure of NdSrMn2O5+δ was identified through X-ray diffraction (XRD) and neutron powder diffraction (NPD) at room temperature (RT), which indicated the formation of a layered structure in orthorhombic symmetry in the Pmmm (no. 47) space group. Rietveld refinement of the neutron diffraction data has confirmed the orthorhombic symmetry with unit cell parameters (a = 3.8367 (1) Å, b = 3.8643 (2) Å, and c = 7.7126 (1) Å), atomic positions, and oxygen occupancy. Thermogravimetric analysis revealed the total weight loss of about 0.10% for 20–950°C temperature, which occurred mainly to create oxygen vacancies at high temperatures. Rietveld analyses concurred with the XRD and neutron data allowing correlation of occupancy factors of the oxygen sites.
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| 4. |
- Afroze, Shammya, 1987, et al.
(författare)
-
Neutron and X-ray powder diffraction data to determine the structural properties of novel layered perovskite PrSrMn2O5+δ
- 2020
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Ingår i: Data in Brief. - : Elsevier BV. - 2352-3409. ; 29
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Tidskriftsartikel (refereegranskat)abstract
- The data presented in this article are related to the formation of a novel layered perovskite oxide material, PrSrMn2O5+δ, through a solid-state synthesis route. Here, we present the high-resolution neutron powder diffraction and the X-ray powder diffraction data at room temperature. The new perovskite material crystallizes in the orthorhombic symmetry. Interpretation of this data can be found in a research article titled “Insight of novel layered perovskite PrSrMn2O5+δ: A neutron powder diffraction study” (Shammya et al., 2019) [1].
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| 5. |
- Afroze, Shammya, 1987, et al.
(författare)
-
Structure-conductivity relationship of PrBaMnMoO 6-δ through in-situ measurements: A neutron diffraction study
- 2021
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Ingår i: Ceramics International. - : Elsevier BV. - 0272-8842 .- 1873-3956. ; 47:1, s. 541-546
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Tidskriftsartikel (refereegranskat)abstract
- The structural and electrochemical properties of the double perovskite-type oxide, PrBaMnMoO6-δ, was investigated using neutron diffraction with in-situ conductivity measurement under a dry Argon atmosphere from 25 °C to 700 °C. A Rietveld refinement of the neutron diffraction data confirmed monoclinic symmetry in the P21/n space group. Rietveld refinement also confirms the unit cell parameters of a = 5.6567 (1) Å, b = 5.6065 (2) Å, c = 7.9344 (1) Å and β = 84.43° with reliable atomic positions and refinement factors (R-factors). Neutron diffraction data refinement shows two minor phases (<5%), an orthorhombic AB2O5 type phase of PrMn2O5 in the Pbam (No. 32) space group with unit cell parameters, a = 7.9672 (1) Å, b = 8.9043 (2) Å and c = 5.8540 (1) Å and a scheelite phase of BaMoO4 in the tetragonal I41/a (88) space group with the unit cell parameters, a = b = 5.9522 (1) Å, and c = 12.3211 (2) Å. Morphological images revealed a porous and intertwined microstructure. In-situ conductivity measurement shows that the total conductivity of this material was 130.84 Scm−1 at 700 °C.
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