Comparison of 3D-cDFT and GCMC simulations for fluid–structure analysis in amorphous carbon nanoporous materials

Abstract

Investigating fluid behavior in nanoporous materials is essential for gas storage, separation, and catalysis applications. Here, we present a comparison of two computational methods for fluid–structure analysis in amorphous nanoporous carbon materials: three-dimensional (3D) classical density functional theory (cDFT) and grand canonical Monte Carlo (GCMC) simulations. We extended our recent development of 3D-cDFT to allow density-profile analysis without symmetry assumptions, enhancing its applicability to a broader range of porous materials. We provide a theoretical overview and discuss the advantages and limitations of each method. Our results highlight the accuracy of both 3D-cDFT and GCMC simulations while emphasizing differences in computational cost, precision, and scope. We also explore the impact of the non-crystalline structure of amorphous carbon nanopores on fluid structure and adsorption isotherms, as well as fluid–fluid and fluid–solid interactions. We offer insights for selecting computational methods in fluid structure analysis of nanoporous materials, guiding future research and optimization in advanced material development for diverse applications.