Synthesis of Stable Bismuth Silicate with Sillenite Structure in the Na2O–Bi2O3–SiO2 System

• Published in: Inorganic materials : applied research 2018, Vol.9 (2), p.221-226
• Main Authors: Yastrebinskii, R. N., Bondarenko, G. G., Pavlenko, A. V.
• Format: Article
• Language: English
• Subjects: Bismuth oxides; Bismuth silicate; Bismuth silicon oxide; Bismuth trioxide; Chemistry; Chemistry and Materials Science; Crystal structure; Industrial Chemistry/Chemical Engineering; Inorganic Chemistry; Materials of Power Engineering and Radiation-Resistant Materials; Materials Science; Phase composition; Phase transitions; Polymer matrix composites; Radiation shielding; Silicon dioxide; Synthesis
• ISSN: 2075-1133; 2075-115X
• DOI: 10.1134/S2075113318020326

A combined method for synthesizing a highly dispersed (0.8–2.5 μm) hydrophobic Na 2 O–Bi 2 O 3 –SiO 2 powder (NBS powder) based on solutions of sodium methyl siliconate and bismuth nitrate is studied. The powder is synthesized at a reduced temperature (100°C). The microstructure and the phase composition of the resulting compounds in the Na 2 O–Bi 2 O 3 –SiO 2 system at different processing temperatures are investigated. The structural phase transformations in the mineral phases of NBS powder are revealed in the temperature range of 100–500°C. The metastable bismuth silicate Bi 2 SiO 5 at 400°C is transformed into stable sillenite with composition Bi 12 SiO 2 0 having a cubic crystal structure ( a = 10.1050 Å). The synthesized NBS powder can be used as a filler to fabricate highly effective constructional radiation-shielding polymer composites with tailored properties.