Sol‐Gel Mono‐ and Poly‐component Nanosized Powders in the Al2O3–TiO2–SiO2–MgO System

Autor: Maria Crisan, Fujio Mizukami, Shuichi Niwa, Maria Zaharescu, Andrei Jitianu
Rok vydání: 2003
Předmět:
Zdroj: Journal of Dispersion Science and Technology. 24:129-144
ISSN: 1532-2351
0193-2691
DOI: 10.1081/dis-120017952
Popis: Sol‐gel processes allow for the synthesis of powders with a more elaborate structure from the point view of composition, purity, size, and size distribution. In the powder case, sol‐gel refers to processing in a liquid medium to obtain a solid, which does not settle under gravity due to the formation of a diffuse network structure (the gel) comprising interparticle contacts. In the presence of water, the precursors undertake the following succession of transformations: hydrolysis→polymerisation→nucleation→growth. Sol‐gel monocomponent Al2O3, TiO2, MgO, and SiO2 powders as well as polycomponent powders in the Al2O3–TiO2–SiO2–MgO system have been obtained and have been characterized by x‐ray diffraction (XRD), IR‐spectroscopy, DTA/TG analysis, transmission electron microscopy (TEM), and BET specific surface area methods. Amorphous and nanosized powders with a tendency towards aggregation have been obtained. In the case of binary and ternary powders the dimension of the particles decreases and the s...
Databáze: OpenAIRE
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