Acid Gas Stability and Selectivity of Rare Earth MOFs

Susan E. Henkelis, Tina M. Nenoff, Dorina Sava Gallis, Grace VincentD. Jon Vogel

Sandia National Laboratories

Herein, we report on the novel application and study of isostructural metal-organic framework (MOF) materials platform
based on RE-DOBDC (RE= Y, Yb, Tb, Eu; DOBDC= 2,5-dihydroxyterephthalic acid) containing coordinatively unsaturated open metal sites (CUSs). In particular, we are interested in understanding the structural and thermal stability of these analogs to caustic gases (NOx, SOx). To do this, we investigated the preferential adsorption of these gases as function of metal identity and examined their performance in complex gas environments.

The MOFs were synthesized under solvothermal conditions and fully characterized by XRD, BET, FTIR and photoluminescence. Bulk gas studies involved NOx generation in an adsorption chamber at room temperature. Each MOF was shown to retain their structural integrity under NOx
exposure. Interestingly, pre-NOx exposure these MOFs exhibit photoluminescence under UV light. However, upon NOx exposure, that emission is quenched. This is indicative of stimuli responsive nature in this multifunctional material.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.