Vogel Dayton J, Rimsza Jessica M, Nenoff Tina M
Nanoscale Sciences Department, Sandia National Laboratories, Albuquerque, NM, 87185, USA.
Geochemistry Department, Sandia National Laboratories, Albuquerque, NM, 87185, USA.
Angew Chem Int Ed Engl. 2021 May 10;60(20):11514-11522. doi: 10.1002/anie.202102956. Epub 2021 Apr 8.
Reactive gas formation in pores of metal-organic frameworks (MOFs) is a known mechanism of framework destruction; understanding those mechanisms for future durability design is key to next generation adsorbents. Herein, an extensive set of ab initio molecular dynamics (AIMD) simulations are used for the first time to predict competitive adsorption of mixed acid gases (NO and H O) and the in-pore reaction mechanisms for a series of rare earth (RE)-DOBDC MOFs. Spontaneous formation of nitrous acid (HONO) is identified as a result of deprotonation of the MOF organic linker, DOBDC. The unique DOBDC coordination to the metal clusters allows for proton transfer from the linker to the NO without the presence of H O and may be a factor in DOBDC MOF durability. This is a previously unreported mechanisms of HONO formation in MOFs. With the presented methodology, prediction of future gas interactions in new nanoporous materials can be achieved.
金属有机框架材料（MOF）孔隙中反应性气体的形成是框架破坏的一种已知机制；理解这些机制对于未来的耐久性设计至关重要，是下一代吸附剂的关键。在此，首次使用大量从头算分子动力学（AIMD）模拟来预测混合酸性气体（NO和H₂O）的竞争性吸附以及一系列稀土（RE）-DOBDC MOF的孔内反应机制。MOF有机连接体DOBDC去质子化的结果是亚硝酸（HONO）的自发形成。DOBDC与金属簇的独特配位使得在没有H₂O的情况下质子能够从连接体转移到NO，这可能是DOBDC MOF耐久性的一个因素。这是MOF中HONO形成的一种此前未报道的机制。通过所提出的方法，可以实现对新型纳米多孔材料中未来气体相互作用的预测。
