Nitrogen-doped carbonaceous materials obtained by CVD process from mesoporous silica for sulfides oxidation
| Autor: | Luisa E. Milagre, Tatiana A. Ribeiro-Santos, Maria Helena Araujo, Mateus Carvalho Monteiro de Castro, Vitor Fernandes De Almeida, Sara Silveira Vieira, Ana Paula C. Teixeira |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Reactive nitrogen
chemistry.chemical_element 02 engineering and technology General Chemistry Carbon nanotube Mesoporous silica 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Nitrogen Catalysis 0104 chemical sciences Nanomaterials law.invention chemistry.chemical_compound chemistry law Pyridine 0210 nano-technology Carbon Nuclear chemistry |
| Zdroj: | Catalysis Today. 344:32-40 |
| ISSN: | 0920-5861 |
| Popis: | In this work, we describe the synthesis of N doped carbon nanomaterials from mesoporous silica impregnated with iron (10 wt%), using acetonitrile as carbon and nitrogen source by CVD process at 600, 650, 700 and 800 °C. The obtained materials showed a N/C content between 8.3–10.1% and a carbon content between 14 and 31%. Results of TEM, TG, elemental analysis, Raman spectroscopy and XRD showed that higher temperatures synthesis has led to the formation of high content and more organized carbon nanostructures, i.e., carbon nanotubes and bamboo-like structures with higher nitrogen contents in their structure. On the other hand, XPS results showed that the carbon structures obtained at 800 °C have preferential the presence of less reactive nitrogen species, i.e. graphitic nitrogen, while the materials obtained at 600 and 650 °C preferentially have the presence of more reactive nitrogen groups such as pyridine. These materials were used as catalysts for the sulfides oxidation. The type of nitrogen group present in the carbon structure influenced directly the activity of the materials. The catalysts obtained at lower temperatures showed the best kinetics of oxidation sulfides, which was related to the presence of a higher content of more reactive nitrogen groups. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect