York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom.
Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
Langmuir. 2023 May 2;39(17):6113-6125. doi: 10.1021/acs.langmuir.3c00256. Epub 2023 Apr 18.
Currently, more than 100 isotherm models coexist for the six IUPAC isotherm types. However, no mechanistic insights can be reached when several models, each claiming a different mechanism, fit an experimental isotherm equally well. More frequently, popular isotherm models [such as the site-specific models like Langmuir, Brunauer-Emmett-Teller (BET), and Guggenheim-Anderson-de Boer (GAB)] have been applied to real and complex systems that break their basic assumptions. To overcome such conundrums, we establish a universal approach to model all isotherm types, attributing the difference to the sorbate-sorbate and sorbate-surface interactions in a systematic manner. We have generalized the language of the traditional sorption models (such as the monolayer capacity and the BET constant) to the model-free concepts of partitioning and association coefficients that can be applied across the isotherm types. Through such a generalization, the apparent contradictions, caused by applying the site-specific models alongside with cross-sectional area of sorbates for the purpose of surface area determination, can be eliminated straightforwardly.
目前，对于六种 IUPAC 等温热力学模型，共存着超过 100 种的等温热力学模型。然而，当几个声称不同机制的模型都能很好地拟合一个实验等温热力学时，就无法获得机械洞察力。更常见的情况是，流行的等温热力学模型（如特定于位点的模型，如 Langmuir、Brunauer-Emmett-Teller (BET) 和 Guggenheim-Anderson-de Boer (GAB)）已被应用于打破其基本假设的真实和复杂系统。为了克服这些难题，我们建立了一种通用方法来模拟所有等温热力学类型，系统地归因于吸附质-吸附质和吸附质-表面相互作用的差异。我们已经将传统吸附模型的语言（如单层容量和 BET 常数）推广到可以应用于所有等温热力学类型的无模型分割和缔合系数概念。通过这种推广，可以直接消除由于同时使用特定于位点的模型和吸附质的横截面积来确定表面积而引起的明显矛盾。
