Zeolite RHO-Type Net with the Lightest Elements

Abstract

Reported here are two highly porous examples of MOCOFs, a new family of framework materials seamlessly integrating the coordinate bonds of metal-organic frameworks (MOFs) and covalent bonds of covalent organic framework materials (COFs). These two materials represent the lightest zeolite RHOs. Their synthesis is an extraordinary example in which the structure-directing effect of the substituent groups on the cross-linking imidazolyl ring strikes a perfect balance with their pore narrowing effect, leading to the creation of a very open zeolite RHO topology with highly accessible internal pores, characterized by a large surface area of 1818 m(2)/g and a high CO(2) storage capability as high as 35.6 cm(3)/g at 760 Torr and 273 K.

Biologically derived metal organic frameworks

“…[191] Recently, it has become of particular interest to create tetrahedral MOFs that would share structural topologies and coordination factors similar to zeolite chemistry. [194][195][196][197] Tetrahedral imidazolate frameworks (TIF) tetrahedrally coordinated with divalent cations (Zn II or Co II ) by the uni-negative (when an atom only accepts one electron) imidazolate ligands. [198][199][200][201][202] A new approach was taken by Zhang et al by adding an auxiliary uninegative ligand into a zinc-imidazolate tetrahedral assembly to generate tetrahedral frameworks with the formula Zn(Im)x(L2)2-x, where L2 is (Ade)(Int) in TIF-Al, (Im)3(Int) in TIF-A2 and (Im)(Int)2(OH) in TIF-A3.…”

Mechanical Properties of Dense Zeolitic Imidazolate Frameworks (ZIFs): A High‐Pressure X‐ray Diffraction, Nanoindentation and Computational Study of the Zinc Framework Zn(Im)2, and its LithiumBoron Analogue, LiB(Im)4

“…[11] In another recent breakthrough, a family of lightweight ZIF analogues of composition LiB(Im) 4 has been reported. [12,13] These boron imidazolate frameworks (BIFs) are the I-III analogues of the ZIFs, with alternate Zn cations being replaced by Li and B, respectively. We have studied the mechanical properties of the Zn-containing ZIFs in considerable detail, [14] showing among other things that their Youngs moduli (E) and hardnesses (H) decrease as the frameworks become more open.…”

Zeolitic BIF Crystal Directly Producing Noble-Metal Nanoparticles in Its Pores for Catalysis

“…With large internal surface areas and uniform pore and cavity sizes, MOFs share a number of structural and catalytical properties of inorganic zeolites789. Typical zeolite-like MOF examples are zeolitic imidazolate frameworks (ZIFs) and boron imidazolate frameworks (BIFs)1011121314151617. Both ZIFs an BIFs adopt tunable zeolite-type topologies (e.g., SOD, RHO, LTA etc) and have promising applications for gas storage and separation1116.…”

“…They contain tetrahedral cations (e.g., Li + Cu + or Zn 2+ ) linked by various pre-synthesized boron imidazolate complexes12131415. One distinct advantage of the BIFs system is that, both four-substituted B(mim) 4 − ligand and three-substituted BH(mim) 3 − ligand can be readily synthesized prior to solvothermal assembly.…”