MOF surface morphology governs interfacial pore architecture and CO₂ dynamics in mixed matrix membranes

Abstract

Mixed matrix membranes (MMMs), which embed metal–organic frameworks (MOFs) within polymers, offer a promising platform for next-generation, energy-efficient separations. However, the nano-structuring of the MOF/polymer interface and its influence on the MMM performance remains poorly understood. Here, we uncover two fundamental design principles that bridge this gap enabled by an automated, graph theory enhanced molecular simulation platform. First, we demonstrate that MOF surface morphology, specifically its planarity and roughness, plays a decisive role in shaping the topology of the interfacial pore network, including its dimensionality, connectivity, and spatial organization. Second, we show that this pore topology critically governs interfacial CO₂ dynamics: highly interconnected and continuous networks facilitate efficient translational and rotational motion, whereas fragmented architectures severely limit molecular mobility. Beyond providing a deep molecular-level understanding, this work introduces a new design paradigm: deliberate tuning of MOF surface morphology emerges as a powerful strategy to control interfacial nanostructure and optimize gas dynamics. Together, these findings open an unexplored pathway for the rational design of high-performance MMMs for advancing energy-efficient separation technologies.