Coupling structural, adsorption, and mechanical properties of nanoporous carbons using advanced molecular simulation methods
Creators: name: Corrente, Nicholas J.
Publisher: name: No Publisher Supplied
Year: 2025

description: Nanoporous carbons are integral to numerous industries, including mixture separations, carbon capture, batteries, and electrodes. These carbons are composed of highly disordered graphene-like domains that form networks of convoluted pores with broad size distributions ranging from ultramicropores (&lt;0.7 nm) to mesopores (&gt;2 nm). Traditional pore characterization techniques have been extensively applied to predict the properties of practical carbons; however, these methods predominantly rely on the adsorption of pure fluids in simplified, rigid pore models, which cannot fully capture the complex interplay between mixture adsorption, pore space morphology, and structure flexibility.This dissertation extends the traditional techniques through a progression of increasingly sophisticated modeling approaches. First, a novel thermodynamic deformation model, based on the binary Langmuir adsorption model, is developed to predict mixture-induced deformation from pure component measurements. The model's effectiveness is demonstrated using CH4/CO2 mixtures in hard coals, where it successfully predicts both adsorption capacity and volumetric strain under geological conditions. Next, the applicability of Density Functional Theory (DFT) calculations, coupled with Statistical Associating Fluid Theory (SAFT-DFT), is explored to predict mixture adsorption and subsequent deformation of slit-shaped carbon nanopores. The SAFT-DFT results show excellent agreement with atomistic Grand Canonical Monte Carlo (GCMC) simulations while requiring only a fraction of the computational cost, revealing important insights into the nonmonotonic strain behavior and molecular packing effects.The focus then shifts to more realistic material representations through the development and characterization of three-dimensional carbon models. These models exhibit disordered networks of pores between corrugated and defected fragments of graphene sheets, better representing the complex morphology of practical carbons. A selected model is fully characterized using both geometric and adsorption methods, demonstrating remarkable agreement between its predicted adsorption capacities for various gases (N2, CO2, SO2, and hydrocarbons) and experimental measurements on the practical Norit R1 Extra activated carbon. Finally, a hybrid Monte Carlo/Molecular Dynamics simulation scheme is developed to directly simulate adsorption-induced deformation in these 3D models. This approach reveals complex relationships between carbon density, pore morphology, and deformation behavior, while providing novel insight into how mixture composition affects structural response.This dissertation represents a significant advancement in the development of porous material characterization techniques, providing new computational tools and theoretical frameworks for understanding and predicting the coupled structural, adsorption, and mechanical properties of nanoporous carbons. The methods developed here have important implications for optimizing materials in applications ranging from gas separation and storage to carbon capture and sequestration.