Microstructure and chemical analysis of PAN-based activated carbon fibers prepared by different activation methods

Activated carbon fiber (ACF) is a microporous carbonaceous adsorbent, which is developed from organic precursors either by physical activation or chemical activation. Polyacrylonitrile (PAN)-based ACFs are amorphous graphtic carbon, consisting of SP exp 2 hexagonal carbon layers with different pore sizes ranging from micropores to macropores. The adsorption properties result from their remarkable surface and structural properties, which manifest themselves in high specific surface area and adsorption capacity. These in turn arise from the presence of a reasonable amount of micropores. The microstructure of AM is developed during activation, normally by partial gasification in steam and/or carbon dioxide, it is influenced by many factors, such as the degree of activation and the conditions used for carbonization. The properties of ACFs are determined by their microstructure, it is therefore important to investigate the microstructure of ACFs in terms of specific surface area, micropore volume, pore size distributions (PSDs), surface chemistry and so on.