(696c) Influence of Missing Linker and Missing Cluster Defects on the Thermal Conductivity of Metal-Organic Framework UiO-66

Metal-organic frameworks (MOFs) have received significant attention due to their diverse range of applications, such as gas storage, separations, and sensing. MOFs are crystalline, highly porous, tunable materials with nanoscopic pores that are self-assembled from metal nodes and organic linkers. In gas adsorption applications, their practical utility depends on how fast it can dissipate the exothermic thermal energy generated during the adsorption process. Thus, managing heat in MOFs is an important and often ignored challenge in many gas storage applications. Over the past decade, the thermal transport properties of MOFs have attracted more attention. Past work focused on the influence of the presence of adsorbates, pore size and shape, interpenetration, and node-linker interface on the thermal transport characteristics of MOFs. In all those studies, MOF structures have been assumed to be defects free, although defects are naturally present in real MOFs and are known to affect their physical and chemical properties. This work investigates the influence of missing linker and missing cluster defects on the thermal conductivity of well-known MOF, UiO-66, using the Molecular Dynamics (MD) simulation and the Green-Kubo method. We found that missing cluster defects can reduce the thermal conductivity more significantly than the missing linker defects. We show that both missing linker and missing cluster defect concentrations, if controlled, can be used to tune the thermal conductivity of MOFs.