Carbon materials are one of the most widely used substances for gas adsorption. While most of the recent work focuses on enhancing the adsorption capacity, there is still a lack of understanding the fundamentals involved in gas adsorption processes on carbon surfaces as well as in voids of porous carbons. CNTs represent ideal model systems, offering a well-defined morphology as well as interior and surface characteristics e.g. tuneable tube diameters and surface defect sites.
In our contribution we will present experimental and theoretical findings on adsorption studies of N2, CO2 and SO2 on vertically aligned 3D CNT array structures. These structures represent free standing films, are catalyst free and retain their highly aligned structure during gas absorption. These CNT array structures can even be modified chemically as well as structurally while still retaining their aligned morphology. High pressure gas adsorption studies were carried out on chemically and structurally modified 3D CNT arrays to understand the influence, both experimentally and theoretically, of the different parameters which are responsible for gas adsorption in these important carbon materials