Preparation of Porous Carbon by Defluorination of Poly(tetrafluoroethylene) and the Effect of γ-Irradiation on the Polymer
| Autor: | Soshi Shiraishi, Noriko Yoshizawa, Asao Oya, Tien-Tzu Liang, Yoshio Yamada |
|---|---|
| Rok vydání: | 2001 |
| Předmět: |
General Chemical Engineering
Potassium chemistry.chemical_element Mineralogy General Chemistry Hydrogen fluoride Potassium fluoride chemistry.chemical_compound symbols.namesake Adsorption chemistry Chemical engineering Materials Chemistry symbols Tetrafluoroethylene Raman spectroscopy Porosity Carbon |
| Zdroj: | Chemistry of Materials. 13:2933-2939 |
| ISSN: | 1520-5002 0897-4756 |
| DOI: | 10.1021/cm010184w |
| Popis: | Porous carbon materials were prepared by direct reduction of poly(tetrafluoroethylene) (PTFE) powder with potassium vapor. After the reaction, the black powder product under vacuum showed a Raman peak at around 1950 cm-1, which was assigned to the C⋮C bond in a polyyne-type structure. After the byproduct, potassium fluoride, was removed, by using hydrogen fluoride, the powder was heat-treated up to 2800 °C in an argon atmosphere. The structural changes of the powder with heat treatment were analyzed by Raman spectroscopy. The changes in the pore structure were examined by N2 adsorption. It was found that the product contains a high amount of mesopores as well as micropores. For example, the meso- and micropore volumes for the carbon heat-treated at 1000 °C were 669−844 and 200−233 mm3/g, respectively. The same experiments were performed by using γ-irradiated PTFE powder. The product gave a more porous structure, i.e., a higher total surface area of 1385−1516 m2/g and mesopore area of 877−1126 m2/g, while ... |
| Databáze: | OpenAIRE |
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