Хімічні перетворення сполук сірки при синтезі терморозширеного графіту з бісульфату графіту за даними РФС

• Datum: 2011
• Hauptverfasser: Nasiedkin, D. B., Babich, I. V., Plyuto, Yu. V.
• Format: Artikel
• Sprache: Ukrainisch
• Veröffentlicht: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2011
• Online Zugang: https://surfacezbir.com.ua/index.php/surface/article/view/446
• Назва журналу: Surface

The chemical nature and concentration of functional groups on the surface of natural graphite during the synthesis of expanded graphite by intercalation with H2SO4 and H2O2 as an oxidant were investigated using XPS method. The spectra in C1s (296–280 eV) and O1s (540–526 eV) region indicate the presence of alcoholic and phenolic (С−О), ketonic (С=О), ether (C−O−C), ester and carboxylic (О=С−О) functional groups. The spectra in S2p (175–160 eV) region demonstrate the presence of thiophene and thiol (С–S–С, С–SH), sulphone and sulphoxide (>S=O, O=S=O), sulphite and sulphate (HSO3-, HSO4-) functional groups. Intercalation of the natural graphite results in the increase of oxygen and sulphur content from 1.49 to 13.21% at. and from 0.02 to 0.61% at., respectively. After thermal expansion, the oxygen and sulphur content was found to be decreased to the initial levels (1.08 and 0.03% at., correspondingly). It has been found out that concentration of sulphur in expanded graphite is mainly determined by its presence in the natural graphite and intercalation has no effect on the chemical nature and composition of surface functional groups in expanded graphite.