Relating reactivity to structure in cokes and carbon materials: Temperature-programmed oxidation and microscopy techniques

• Published in: Carbon (New York) Vol. 168; pp. 362 - 371
• Main Authors: Andreoli, Sara, Eser, Semih
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 30.10.2020; Elsevier BV
• Subjects: Carbon; Carbon composites; Composite materials; Optical microscopy; Optical properties; Optical texture; Oxidation; Petroleum coke; Polarized light; Polarized-light microscopy; Reactivity; Scanning electron microscopy; Surface functional groups; Temperature-programmed oxidation; Texture; Transmission electron microscopy; Polarized-light microscopy; Carbon composites; Optical texture; Reactivity; Petroleum coke; Surface functional groups; Temperature-programmed oxidation
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2020.06.071

A series of carbon materials and composites has been characterized by temperature-programmed oxidation (TPO), polarized light microscopy (PLM), scanning electron microscopy with energy dispersive X-ray spectroscopy (EDS), and temperature-programmed desorption coupled with mass-spectrometry analysis. For materials containing anisotropic carbons, a consistent relationship was found between oxidation reactivity and optical texture. Polarized-light microscopy in combination with TPO can help assessing the relationships between oxidation reactivity and optical texture of anisotropic carbons. Deconvolution of TPO profiles and PLM observations can effectively identify the individual components of multi-component carbon materials with important implications in structure-property relationships and their applications. For amorphous carbons with isotropic optical textures, TPO profiles were found to be influenced by the surface chemistry of the materials. It appears that the TPO technique under controlled conditions provides a rapid analysis of solids carbons with respect to their structure and properties. This is particularly useful for the analysis of carbon composites with multiple phases in combination with microscopic examination and elemental analysis using EDS. [Display omitted] •Temperature-programmed oxidation easily assesses properties of carbon materials.•For anisotropic carbons, oxidation reactivity relates to optical texture.•For isotropic carbons, surface chemistry influences oxidation reactivity.•Temperature-programmed oxidation identifies components in commercial materials.