Structural Evolution from Noninterpenetrated to Interpenetrated Thorium–Organic Frameworks Exhibiting High Propyne Storage

Abstract

Two thorium−organic frameworks of [Th 6 O 4 (OH) 4 (TFBPDC) 6 (H 2 O) 6 ] n (Th-TFBPDC) and [Th 6 O 4 (OH) 4 (TFBPDC) 4 (HCOO) 4 (H 2 O) 6 ] n (Th-TFBPDC-i) constructed from the 3,3′,5,5′-tetrakis(fluoro)biphenyl-4,4′-dicarboxylate (TFBPDC 2− ) ligand were obtained in a reaction. At an early stage of the reaction, the formation of the three-dimensional (3D) framework of Th-TFBPDC was discovered. At a later stage of the reaction, the complete product of Th-TFBPDC-i was obtained. The structural evolution from a noninterpenetrated network of Th-TFBPDC to a 2-fold interpenetrated network of Th-TFBPDC-i is a dissolution− recrystallization process and rationalized as the four equatorial TFBPDC 2− ligands in an octahedral [Th 6 O 4 (OH) 4 (TFBPDC) 12 ] unit were displaced by four formate ligands to form a [Th 6 O 4 (OH) 4 (TFBPDC) 8 (HCOO) 4 ] unit via a ligand substitution reaction. The large pore volume as well as the strong interactions between the host framework and guest propyne (C 3 H 4 ) molecules demonstrated by computational results endow the highly water-stable Th-TFBPDC with the best-performing C 3 H 4 storage under ambient conditions. This work presents a rare example of structural evolution from a 3D noninterpenetrated network to a 2-fold 3D interpenetrated network and a highly promising metal−organic framework (MOF) for C 3 H 4 storage with a C 3 H 4 uptake of 8.16 mmol g −1 at 298 K. ■ EXPERIMENTAL SECTIONCaution! Thorium nitrate (Th(NO 3 ) 4 •5H 2 O) is a chemically toxic and radioactive reactant. Standard precautions for handling radioactive materials have been followed.

Fluorinated metal–organic frameworks for gas separation

“…The functionalized ligand group position in the MOF structure affects its chemical stability. 72 117 (2) fcu-MOF, Tb-FTZB-MOF: 2-fluoro-4-(1H-tetrazol-5-yl)benzoic acid (H 2 FTZB); 118 2016: (1) NOTT-108:2 0 ,3 0 ,5 0 ,6 0 -tetrafluoro-[1,1 0 :4 0 ,1 00 -terphenyl]-3,3 00 ,5,5 00 -tetracarboxylic acid (H4TPTC), 119 (2) DUT-67-Pfba, [Zr 6 O 6 (OH) 2 (tdc) 4 -(RCOO) 2 ]: RCOO À : pentafluorobenzoic acid (Pfba); 120 2017: [M(L) 2 ]: M = Cu 2+ , Pd 2+ , Pt 2+ and bis(pentafluorobenzoyl)methanido) (L); 69 2018: (1) and ( 2) Cu-PUM210F and PUM210F: [Zn 3 (Fbpba) 1 Á(ndc) 3 Á(DMF)] n , N,N 0 -(perfluoro-1,1 0 -biphenyl-4,4 0 -diyl)diisonicotinamide (F-bpba); 62 2019: (1) F4_UiO-66(Ce) and ( 2) F4_MIL140A(Ce): tetrafluoroterephthalic acid (TFTPA), 121 (3) Iso-MOF-4,3,5-di(4-carboxyphenyl)benzoic acid (H 3 TTCA-F), 122 (4) UPC-106: 3,5-di(4carboxyphenyl)benzoic acid (H 3 TTCA-F); 123 2020: (1) [Ni 0.5 (tpt) 0.5 (R-opa) 0.5 (H 2 O) 0.5 ]: R-opa 2À (fluorinated ligand), 117 (2) JXNU-6, {[Tb 2 (TFBPDC) 3 (H 2 O)]Á 4.5DMFÁ0.5H 2 O} n : tetrafluoroterephthalic acid (H 2 -TFBPDC), 124 (3) UiO-67-F8: octafuorobiphenyl-4,4 0 -dicarboxylic acid (H 2 oFbpdc); 63 2021: (1) {(Et 2 NH 2 )-[In(TBOT)(2,3-FDA)](DEF)(H 2 O) 2 } n : 2,3-HFDA = 2,3-difluorobenzoic acid (HFDA), 125 (2) and ( 3) Ce(IV)-MIL-140-4F and Zr(IV)-MIL-140-4F: tetrafluoroterephthalic acid (H 2 TFBDC), 126 (4) Cu-FINA-1 and (5) Cu-FINA-2: 3-fluoro-isonicotinic acid (HFINA), 64 (6) Dy-MOF, {[(CH 3 ) 2 NH 2 ] 2 [Dy 6 (m 3 -OH) 8 (FTZB) 6 (H 2 O) 6 ]Á(solvent)} n : 2-fluoro-4-(1H-tetrazol-5-yl)benzoic acid (F-H 2 tzba), 127 (7) F-PYMO-Cu: 5-fluoro-2-hydroxypyrimidine (F-pymo), 128 (8) [Th 6 O 4 (OH) 4 (TFBPDC) 4 (HCOO) 4 -(H 2 O) 6 ] n : 3,3 0 ,5,5 0 -tetrakis(fluoro)biphenyl-4,4 0 -dicarboxylate (H 2 -TFBPDC), 129 (9) UPC-200(Al)-F-BIM: 3,5-di(4-carboxyphenyl)benzoic acid (H 3 TTCA-F), 130 (10) Cu-F-pymo: [Cu(F-pymo) 2 (H 2 O) 1.25 ] n : 5-fluoropyrimidin-2-olate (F-pymo). 131 Fig.…”

An Amino-Decorated Self-Catenated Metal–Organic Framework for Efficient Capture and Conversion of CO2

“…Generally, the exploitation of long bridging ligands is an effective approach to assemble networks with large pores, but consequently, the interpenetration, a common entangled mode, often occurs to minimize the porosity of frameworks . The design of polynuclear metal clusters as secondary building units (SBUs) has proven to be one feasible strategy to construct porous MOFs. − The SBUs with high connectivity can not only prevent the framework interpenetration and rigidify the framework but also provide more catalytic open-metal sites. On the other hand, increasing the interactions between the framework and substrates can also enhance the catalytic ability of MOFs.…”

Recent advances in the applications of thorium-based metal–organic frameworks and molecular clusters

“…[30][31][32]34,39,53,60 In addition, the applications of Th-MOFs have been extended to the storage and separation of hydrocarbons. [61][62][63][64] Cationic Th-MOFs for the remediation of anionic species are relatively rare since MOFs with positively charged frameworks represent a much smaller fraction of the MOF family than the neutral and anionic ones. Wang , methyl blue (MB − ), and perfluorooctane sulfonate (PFOS − ).…”

“…30–32,34,39,53,60 In addition, the applications of Th-MOFs have been extended to the storage and separation of hydrocarbons. 61–64…”