Importance of the αs-plot Method in the Characterization of Nanoporous Materials

In this work, an exhaustive study of the calculation of micropore and mesopore volumes with αs-plot method as proposed by Professor Sing is carried out. The method is critically compared with other similar methods such as the Dubinin-Radushkevich, t-plot and those based on density functional theory (DFT). For comparison purposes, several nanoporous materials with different chemical properties were selected. The analysis was segregated into three categories: (i) microporous materials, in which the analyzed samples are activated carbons (ACs) with different pore-size distributions, a single-walled carbon nanotube (SWNT) and a zeolite (MS5A); (ii) mesoporous materials, including ordered mesoporous carbons (CMK-3) and ordered mesoporous siliceous materials (MCM-41 and SBA-15); and (iii) micro-mesoporous materials, in which pillared clays (PILCs) obtained with different metals (Al, Si, Fe and Zr) were studied. To apply the αs-plot method, several standard isotherms previously reported by other authors were con...