Nanoporous MOF-303 Performance for Atmospheric Water Harvesting in the Presence of Airborne Contaminants: GCMC and DFT Simulations

This study assesses the suitability of MOF-303 for atmospheric water harvesting (AWH) in polluted environments using Grand Canonical Monte Carlo (GCMC) and density functional theory (DFT) methods. GCMC simulations validated MOF-303's water adsorption capacity, closely aligned with experimental data. Simulated H2O uptake was 0.50 g/g at 298 K and 3000 Pa, with binding energies for the first four water molecules ranging from −71.86 to −47.35 kJ/mol. MOF-303 exhibited a strong affinity for SO2, with an uptake of 0.40 g/g at 298 K and 3000 Pa, while the uptake of NO and NO2 was minimal. SO2 uptake gradually increased with pressure, unlike the steplike behavior observed in water adsorption, with binding energies increased from −41 to 39.64 kJ/mol for the first four SO2 molecules. In mixed-component scenarios of H2O and SO2, H2O demonstrated dominant adsorption behavior over SO2, even with increasing SO2 concentrations, which delayed the characteristic steep step in the H2O adsorption isotherm. Conversely, SO2 uptake peaked at low pressure and then sharply declined to nearly zero. The maximum selectivity for SO2 over H2O did not exceed 0.3. Overall, MOF-303 proves to be a promising material for AWH, even in polluted environments. This study offers valuable insights for optimizing MOF-303 for practical deployment in diverse environmental settings, enhancing its potential for SO2 detection, capture, and air quality control strategies.