MARTINI-based force fields for predicting gas separation performances of MOF/polymer composites

TL;DR

This study uses coarse-grained simulations to analyze how nanoparticle size and shape influence gas separation efficiency in MOF/polymer composites, providing insights for optimizing materials for industrial applications.

Contribution

It systematically investigates the effects of nanoparticle morphology and size on gas adsorption in MOF/polymer composites using coarse-grained modeling, which was previously unexplored.

Findings

Smaller nanoparticles enhance gas separation performance.

Rhombic dodecahedron nanoparticles outperform cubic ones.

The modeling approach can be integrated into high-throughput screening.

Abstract

MOF/polymer composites have been widely investigated in the past decade for gas separation applications. However, the impact of MOF nanoparticle morphology and size in gas separation have not yet been systematically studied by computer simulation techniques. In this work, coarse grained simulations are deployed to study gas adsorption in ZIF-8/PVDF at the nanoparticle level. Nanoparticles of different morphologies and sizes are explored, and adsorption of CO2, N2 and CH4 is investigated throughout the extension of the bulk and surface of the nanoparticle as well as of the polymer phase. Results reproduce the expected preference for CO2 over the other two gasses. Nanoparticles of smaller sizes provide better separation performance at ambient conditions, while rhombic dodecahedron nanoparticles perform better than cubic ones. This work presents a perspective on the merits and limitations of modelling gas adsorption in MOF/polymer composites at the nanoparticle level via particle-based coarse graining approaches, and provides a methodological set-up which can be integrated into high-throughput schemes, bringing us closer to reaching time- and length scales that can be directly compared with experimental data.