Highly Porous Expanded Graphite: Thermal Shock vs. Programmable Heating

Highly porous expanded graphite was synthesized by the programmable heating technique using heating with a constant rate (20 degrees C/min) from room temperature to 400-700 degrees C. The samples obtained were analyzed by scanning electron microscopy, energy-dispersive spectroscopy, low-temperature nitrogen adsorption, X-ray photoelectron spectroscopy, Raman spectroscopy, thermogravimetry, and differential scanning calorimetry. A comparison between programmable heating and thermal shock as methods of producing expanded graphite showed efficiency of the first one at a temperature 400 degrees C, and the surface area reached 699 and 184 m(2)/g, respectively. The proposed technique made it possible to obtain a relatively higher yield of expanded graphite (78-90%) from intercalated graphite. The experiments showed the advantages of programmable heating in terms of its flexibility and the possibility to manage the textural properties, yield, disorder degree, and bulk density of expanded graphite.

Automated summary

The programmable heating technique proved to be more effective than thermal shock in producing expanded graphite, showing higher efficiency and surface area. This method allows for a relatively higher yield and the management of textural properties, disorder degree, and bulk density of expanded graphite.