Structural analysis of and selective CO₂ adsorption in mixed-ligand hydroxamate-based metal–organic frameworks

Abstract

Two mixed-ligand metal–organic frameworks using benzene-1,4-dihydroxamic acid and isonicotinic acid were synthesized and fully characterized by single-crystal X-ray crystallography as well as N2, H2, and CO2 gas-sorption measurements.

Zn‐Based Metal–Organic Frameworks Using Triptycene Hexacarboxylate Ligands: Synthesis, Structure, and Gas‐Sorption Properties

“…A major advantage of MOFs in comparison to other porous materials is the relative ease of functionalization, where organic moieties can readily be installed on the linker molecules as substituents. Especially the functionalization of MOFs with CH 3 , NH 2 , NO 2 , Cl, Br,CO 2 H, OCH 3 , or SO 3 H functional groups enhances their adsorption performances for various gases (mainly H 2 , CO 2 , and CH 4 ) [29–35] . In this context, we have already reported alkyl‐functionalized MOF‐5, which exhibits an enhanced H 2 ‐uptake capacity and CO 2 /N 2 selectivity compared to its parent MOF‐5 [36,37] .…”

“…Especially the functionalization of MOFs with CH 3 , NH 2 , NO 2 , Cl, Br,CO 2 H, OCH 3 , or SO 3 H functional groups enhances their adsorption performances for various gases (mainly H 2 , CO 2 , and CH 4 ). [29][30][31][32][33][34][35] In this context, we have already reported alkylfunctionalized MOF-5, which exhibits an enhanced H 2 -uptake capacity and CO 2 /N 2 selectivity compared to its parent MOF-5. [36,37] Furthermore, MOFs with smaller pore size exhibit enhanced gas-adsorption capacity.…”

Metal-hydrogen-pi-bonded organic frameworks

“…[38][39][40] Unlike carboxylate groups, hydroxamates allow asymmetric binding modes with metal ions and favor the formation of single metal nodes over polynuclear SBUs. To date, only four MOFs [41][42][43][44] containing hydroxamate ligands have been reported, with only two 41,42 having 3D framework structures.…”

A stable lanthanum hydroxamate metal–organic framework with radical character and electrical conductivity

“…Recently, as a new kind of emerging ligand, hydroxamates have exhibited big potential in fabricating stable MOFs because of strong bonds of chelating hydroxamate groups to metal nodes. 5 However, due to the difficulty in controlling reversible formation of strong metal–hydroxamate bonds, 5 a , e hydroxamate MOFs are rarely reported compared to the widely studied carboxylates or azolates based MOFs. 2 a Further exploration of hydroxamate MOFs is strongly desired.…”