Design and Synthesis of a Water‐Stable Anionic Uranium‐Based Metal–Organic Framework (MOF) with Ultra Large Pores

Abstract

Ionic metal-organic frameworks (MOFs) are asubclass of porous materials that have the ability to incorporate different charged species in confined nanospace by ionexchange.T od ate,h owever,v ery few examples combining mesoporosity and water stability have been realized in ionic MOF chemistry.H erein, we report the rational design and synthesis of awater-stable anionic mesoporous MOF based on uranium and featuring tbo-type topology.T he resulting tbo MOF exhibits exceptionally large open cavities (3.9 nm) exceeding those of all knowna nionic MOFs.B ys upercritical CO 2 activation, arecord-high Brunauer-Emmett-Teller (BET) surface area (2100 m 2 g À1 )f or actinide-based MOFs has been obtained. Most importantly,however,this new uranium-based MOF is water-stable and able to absorb positively charged ions selectively over negatively charged ones,e nabling the efficient separation of organic dyes and biomolecules.

Metal–Organic Frameworks for Water Harvesting from Air

“…Highly charged metals such as Ti +4 , Zr +4 , and Hf +4 tend to form MOFs with high stability toward water as illustrated by frameworks such as UiO‐66 [Zr 6 O 4 (OH) 4 (BDC) 6 ], MOF‐801 [Zr 6 O 4 (OH) 4 (fumarate) 6 ], or DUT‐67 [Zr 6 O 6 (OH) 2 (TDC) 4 (Ac) 2 , where TDC = 2,5‐thiophenedicarboxylate and Ac = acetate] . Recently it was reported, that highly charged U +6 can be used to prepare an ionic framework with outstanding water‐stability . More precise considerations should also include the polarizability of the metal.…”

Structure-Directing Effects of Coordinating Solvents, Ammonium and Phosphonium Counterions in Uranyl Ion Complexes with 1,2-, 1,3-, and 1,4-Phenylenediacetates

“…Although they are attractive and readily available ligands, the three isomeric 1,2-, 1,3-and 1,4phenylenediacetates (1,2-, 1,3-and 1,4-pda 2-) are newcomers in the field of uranyl-organic coordination polymer [1][2][3][4][5] and porous frameworks [6][7][8] studies, in which polycarboxylates are staple assemblers, and they have been the subject of only two reports up to now. 9,10 These anions unite a rigid phenylenic platform and two flexible arms, thus displaying a greater geometric variety than the phenylenedicarboxylate analogues, while, as with the latter, the existence of three isomeric forms allows for an assessment of the effect of the variable separation between the coordinating groups on the periodicity and topology of the assemblies formed.…”

“…With KPIs in the range of 0.70-0.73, the packings in 3-6 are quite compact and no solvent-accessible space is present. 15The two complexes [H2NMe2]2[(UO2)2(1,2-pda)3]H2O(7) and [H2NMe2]2[(UO2)2(1,2pda)3]3H2O (8), which involve the same ligand isomer, counterion, and stoichiometry, present close similarities and will be described together. In both cases, the two independent uranium cations are chelated by three carboxylato groups (hexagonal bipyramidal environment), and the three independent, bis-chelating 1,2-pda 2ligands are in the trans conformation.…”

Bottom-up construction of a superstructure in a porous uranium-organic crystal

“…To test the accessibility of the large pores through the 3.1-and 3.6-nm apertures of the framework, we studied the uptake of two similar-sized proteins, cytochrome c (Cyt-c, 3.6 × 2.4 × 2.2 nm) and a-lactalbumin (a-La, 4.8 × 1.8 × 1.8 nm) with different isoelectric points (10.3 for Cyt-c, 4.5 for a-La). Given the isoelectric points, the two proteins should carry different surface charges (positive for Cyt-c, negative for a-La) in neutral aqueous solution (13). As expected, NU-1301 adsorbed the positively charged Cyt-c but not the negatively charged a-La ( fig.…”

“…1A). These same triangular nodes, [UO 2 (RCOO) 3 ] − , were used as building blocks to construct NU-1300 by using tetratopic linkers to give a 4,3-connected framework with tbo topology (13). We expected that the assembly of [UO 2 (RCOO) 3 ]…”