Degree of functionalization and stability of fluorine groups fixed to carbon nanotubes and graphite nanoplates by CF4 microwave plasma
| Autor: | Víctor K. Abdelkader-Fernández, Manuel Pérez-Mendoza, Francisco Morales-Lara, Rafael López-Garzón, María Domingo-García, F.J. López-Garzón, M.L. Godino-Salido, Celeste García-Gallarín, Manuel Melguizo |
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| Rok vydání: | 2015 |
| Předmět: |
Materials science
Graphene Intercalation (chemistry) Selective chemistry of single-walled nanotubes General Physics and Astronomy chemistry.chemical_element Surfaces and Interfaces General Chemistry Carbon nanotube Condensed Matter Physics Surfaces Coatings and Films law.invention Chemical engineering chemistry law Fluorine Organic chemistry Surface modification Thermal stability Graphite |
| Zdroj: | Applied Surface Science. 357:1410-1418 |
| ISSN: | 0169-4332 |
| Popis: | The fluorination of graphite nanoplates (GNPs) and multi-wall carbon nanotubes (MWCNTs) by CF4 cold plasma is reported. The aim is to analyze the influence of the textural characteristics in the degree of fluorination and in the thermal stability of the fluorine groups. We have used thermal programmed desorption which clearly discriminates the nature of the desorbing species and their stability. The degree of fluorination of both materials is similar up to 20 min of treatment and then it decreases in GNPs at longer treatments. Nevertheless, the fluorine content in MWCNTs keeps increasing after 45 min. This different evolution of the fluorination degree with the time is related to the surface areas. The fluorine bonding is produced not only in defects and irregularities but also on the external graphene sheets of both materials, and it results in up to eight different chemical environments having different thermal stabilities from 150 °C up to temperatures higher than 900 °C. The fluorination increases the electronic states near the Fermi level of the nanotubes whereas it does not affect the electronic properties of graphite nanoplates. It is shown that no intercalation compounds are formed and that the textural characteristics of the materials remain unchanged after fluorination. |
| Databáze: | OpenAIRE |
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