The evaluation of the surface heterogeneity of carbon blacks from the lattice density functional theory

Recently developed two lattice density functional theory (DFT) models are verified experimentally. For this purpose the experimental nitrogen isotherms on carbon blacks at 77 K (M4040 and M32B) were carefully measured by the volumetric apparatus. Moreover, the additional nitrogen data on Sterling FT and SAO carbon blacks were taken from the literature and analyzed. The main goal of this study is the evaluation of the adsorption energy distribution function (and differential adsorption enthalpy at zero coverage) by the new powerful tool based on the lattice DFT formalism proposed by Do and Do and Aranovich and Donohue. New algorithms are proposed for this purpose. The quantitative agreement between these two independent approaches is recognized. The presented in this study new heterogeneous lattice DFT model seems to be very promising one in the investigation of flat surfaces heterogeneity effects