Preparation of Expanded Graphite-based Composites by One Step Impregnation

A new method for preparing expanded graphite-based composites (EGCs) was developed. The obtained samples were characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM) and nitrogen adsorption. The experimental results indicated that the EGCs was not simply mechanical mixture of EG and activated carbon, instead the activated carbon was coated on the surface of interior and external pores of the EG in the form of thin carbon layer. The thickness of the activated carbon layer was nearly one hundred nanometers by calculation. It was shown that the higher the impregnation ratio and the activation temperature were, the easier the porosity development would be. And the BET surface area and the total pore volume were as high as 1978 m(2)/g and 0.9917 cm(3)/g respectively at 350 degrees C with an impregnation ratio of 0.9.