PNNL

Abstract

For the first time, a series of well-reported mesoporous metal–organic frameworks (MOFs) have been tested for R134a fluorocarbon adsorption. Differences in sorption behavior were attributed to varying porosities and topologies. All mesoporous MOFs exhibited excellent, reversible R134a adsorption capacities and among them, NU-1000 provided an exceptional fluorocarbon uptake of ~170 wt% near saturation, which is among the highest values reported so far for MOFs. N2 sorption, high-resolution STEM, and micro calorimetry were used to further explore the relation between the features of NU-1000 and the exceptionally high R134a uptake capacity. Such high performance materials with the appropriate equilibrium isotherm behavior provide significant potential for adsorption cooling systems operating on pressure swing cycles. These results provide evidence that mesoporous MOFs, especially those with hierarchical structure, are promising candidates for chiller applications.