Modification of micro-crystalline graphite and carbon black by acetone, toluene, and phenol

Abstract

The chemical interactions of two types of graphite and two types of carbon black (CB) with acetone, toluene, and phenol were studied in order to evaluate the influence of chemical treatment on the structure and morphology of the carbon phases. The experimental treatment of carbon phases was carried out at room temperature for 1 hour. The chemical and phase composition were studied by x-ray photoelectron (XP) and Raman spectroscopies, while the morphology and structure were determined by powder x-ray diffraction, as well as transmission electron microscopy techniques. To shed light on the most probable explanation of the observed results, we performed simulations and calculations of the binding energies of acetone, toluene, and phenol with model carbon phases: a perfect graphene sheet and a defective graphene sheet containing various structural defects (vacancies as well as zigzag and armchair edges). Simulations show that all non-covalent and most covalent coupling reactions are exothermic, with acetone coupling having the higher calorimetric effect. Based on the results of the simulations and the XP spectroscopy measurements, the probable reactions taking place during the respective treatments are outlined. The conducted studies (both theoretical and experimental) show that the treatment of graphite powders and CB with acetone, toluene, or phenol can be used as a preliminary stage of their modification and/or functionalization, including their conversion into graphene-like (defective graphene, reduced graphene oxide, and/or graphene oxide) phases. For example, the treatment of SPHERON 5000 with acetone significantly facilitates their subsequent modification with laser radiation to graphene-like phases.