Gauden Piotr A, Terzyk Artur P, Jaroniec Mietek, Kowalczyk Piotr
N. Copernicus University, Department of Chemistry, Physicochemistry of Carbon Materials Research Group, Gagarina St. 7, 87-100 Toruń, Poland.
J Colloid Interface Sci. 2007 Jun 1;310(1):205-16. doi: 10.1016/j.jcis.2007.01.082. Epub 2007 Feb 3.
It is well known that the bimodal shape of the pore size distribution (PSD) curves is typical for various carbonaceous materials (of different origin and/or treated thermally or chemically). A systematic investigation of this effect has been discussed using the Nguyen and Do method with proposed recently the ASA algorithm. A series of numerically generated adsorption isotherms (N(2), T=77 K) and experimental data were analyzed. We investigated various possible situations related to the shape of the PSD curves, i.e., the intensity of the both peaks, their mutual location and the vanishing of one of them. Moreover, the problem in the similarity of the local adsorption isotherms from the range of pore widths corresponding to the gap between peaks is discussed. The analysis of obtained results (as well as published by others) shows that the bimodal shape of the pore size distributions is a characteristic feature for many adsorbents possessing even a small amount of micropores. It is shown that this feature results from the similarity of the local adsorption isotherm in the range of the pore widths for which the gap between peaks (related to the primary and secondary micropore filling mechanism) exists.
众所周知，孔径分布（PSD）曲线的双峰形状对于各种碳质材料（不同来源和/或经过热或化学处理）来说是典型的。已经使用Nguyen和Do方法以及最近提出的ASA算法对这种效应进行了系统研究。分析了一系列数值生成的吸附等温线（N₂，T = 77 K）和实验数据。我们研究了与PSD曲线形状相关的各种可能情况，即两个峰的强度、它们的相互位置以及其中一个峰的消失。此外，还讨论了对应于峰之间间隙的孔径范围内局部吸附等温线的相似性问题。对所得结果（以及其他人发表的结果）的分析表明，孔径分布的双峰形状是许多甚至含有少量微孔的吸附剂的特征。结果表明，这一特征源于在存在峰之间间隙（与初级和次级微孔填充机制有关）的孔径范围内局部吸附等温线的相似性。
