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Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV
Published on: December 29, 2016
New binary and ternary SiO2 composites with Fe2O3 and Co2.74O4 and the evaluation of their γ-radiation shielding
Ahmed M A El-Seidy1, Mohamed S El-Okaily2, Islam M Nabil3
1Inorganic Chemistry Department, Advanced Materials Technology and Mineral Resources Research Institute, National Research Centre, El-bohouth St., P.O. 12622, Dokki, Cairo, Egypt. am.elseidy@nrc.sci.eg.
Abstract:
A new series of binary and ternary nanocomposites contains cobalt oxide or iron/cobalt oxides were manufactured to increase silicon dioxide γ shielding power. XRD indicated the presence of Co as Co2.74O4 (COD: 1528446) and the presence of iron as Fe3O4 (COD: 9002318 and 9005814). Using Profex, the Rietveld refinements were carried out. The Rw, Rex, x2, and Gof were 4.49, 4.34, 1.07, and 1.03, respectively, indicating good refinement parameters. XPS indicated the presence of Si ([Formula: see text]), Fe (Fe[Formula: see text]O[Formula: see text]) and cobalt ([Formula: see text] and [Formula: see text]). TEM analysis showed that all metal oxide@SBA-15 solids have characteristic and well-organized SBA-15 structures. The γ-radiation shielding for the prepared samples were investigated via the Monte-Carlo code (MCN) and Phy-X software. The results confirmed that, adding high concentrations of cobalt-oxide and hematite increases the linear attenuation significantly. The SiCoFe-3 sample, which contains the highest content of cobalt-oxide and hematite, has the best γ-radiation shielding capability among all the synthesized SiCo/SiCoFe samples.
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