(316a) Unraveling the Role of Topology in the Thermal Transport Limits of Metal-Organic Frameworks: A High-Throughput Study.

Metal-Organic Frameworks (MOFs) are a unique class of crystalline materials that possess high porosity and surface area, making them promising candidates for various applications, including gas storage, separation, and catalysis. However, their practical utilization is often hindered by the challenge of managing the exothermic heat generated during gas adsorption. Despite their potential, the thermal transport properties of MOFs have received relatively little attention, leading to a lack of fundamental knowledge about the structure-thermal conductivity relationships required for designing MOFs with specific thermal properties. To address this gap, we performed a comprehensive high-throughput screening of hypothetical MOFs using classical molecular dynamics simulation and the Green-Kubo method. We screened 10,194 hypothetical MOFs that are generated using the ToBaCCo-3.0 code, considering several important structural and compositional features, such as density, pore size, surface area, void fraction, node-linker mass mismatch, and metal node connectivity. Our analysis revealed that small pores, high density, small node-linker mass mismatch, and four-connected metal clusters are associated with high thermal conductivity. Additionally, we identified six hypothetical MOF structures with exceptional thermal conductivity and 36 structures with ultra-low thermal conductivity. Interestingly, the six MOFs with ultrahigh thermal conductivity share a common feature of four-fold coordinated metal nodes that connect the organic linkers perpendicularly. This observation suggests that the topology of MOFs plays a crucial role in determining their thermal conductivity limits. Overall, our study provides new insights into the design principles of MOFs with tailored thermal properties and highlights the importance of considering the structural characteristics in designing high-performance MOFs for various applications.