Preparation of cubic SiC from δ-Na2Si2O5/carbon nanocomposite using cobalt catalyst

Silicon carbide (SiC) was prepared by carbothermal reduction of a crystalline-layered sodium silicate (δ-Na2Si2O5)/carbon nanocomposite (LCN), which contained a stacked carbon film embedded with cobalt between the silicate layers. Subsequent sintering of this mixture for 3 h at 1000–1350°C resulted...

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Bibliographic Details
Main Authors: Kyeong-Won Park, Oh-Yun Kwon
Format: Article
Language:English
Published: Taylor & Francis Group 2019-12-01
Series:Science and Technology of Advanced Materials
Subjects:
Online Access:http://dx.doi.org/10.1080/14686996.2019.1619479
Description
Summary:Silicon carbide (SiC) was prepared by carbothermal reduction of a crystalline-layered sodium silicate (δ-Na2Si2O5)/carbon nanocomposite (LCN), which contained a stacked carbon film embedded with cobalt between the silicate layers. Subsequent sintering of this mixture for 3 h at 1000–1350°C resulted in the formation of graphitic carbon and SiC. Meanwhile, sintering without a cobalt catalyst resulted in the formation of graphitic carbon, regardless of the temperature. The use of a cobalt catalyst allowed the formation of a pure SiC phase at 1350°C. The formed SiC had an irregular worm-like morphology, with a particle size of ~5 µm. The Brunauer-Emmett-Teller surface areas of graphitic carbon and SiC were 28–150 and ~7.0 m2/g, respectively. We concluded that graphite and SiC were produced at this low sintering temperature because of the cobalt catalyst, which facilitated nanomixing of carbon and SiO2 by sandwiching the carbon films between the silicate layers.
ISSN:1468-6996
1878-5514