Molecular Simulation Insights into Acid Gas Interactions within Ni-Based Fluorinated Square-Pillared Metal-Organic...

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Metal-organic frameworks (MOFs) are increasingly vital for gas separation technologies.
• Flue gas treatment faces challenges with acidic gas adsorption in MOFs due to complex interactions.

Purpose of the Study:

• To investigate the adsorption interactions of acidic gases (SO2, CO2, NO2) and their mixtures with the flexible [Ni(1,4-pyrazine)2(AlF5)]n (ALFFIVE-Ni-Pyr) framework.
• To evaluate the impact of guest molecules on the framework's structural dynamics and adsorption capacity.

Main Methods:

• Grand canonical Monte Carlo simulations for guest-host interactions and gas loading.
• Molecular dynamics simulations for framework structural dynamics.
• Density functional theory calculations to confirm gas-framework interactions.

Main Results:

• ALFFIVE-Ni-Pyr exhibits significantly higher adsorption capacity for SO2 compared to CO2 and NO2.
• The framework demonstrates superior performance in separating acidic gases, especially in mixtures.
• Framework flexibility plays a key role in accommodating guest molecules and influencing adsorption.

Conclusions:

• ALFFIVE-Ni-Pyr shows excellent potential for selective acidic gas separation in flue gas treatment.
• Understanding guest-induced dynamics is crucial for optimizing MOF performance.
• This research provides insights for developing advanced MOFs for industrial gas separation applications.