Probing the limits of linker substitution in aluminum MOFs through water vapor sorption studies: mixed-MOFs instead of mixed-linker CAU-23 and MIL-160 materials

Abstract

Only water vapor sorption isotherms were able to reveal the mixed-MOF instead of mixed-linker material formation of CAU-23 and MIL-160.

Unravelling gas sorption in the aluminum metal‐organic framework CAU‐23: CO2, H2, CH4, SO2 sorption isotherms, enthalpy of adsorption and mixed‐adsorptive calculations

“…The steep rise of the S‐shaped CO 2 isotherm of CAU‐23 between 6 to 12 bar is shifted to lower pressures, that is, between 5 to 10 bar in MIL‐53‐TDC. As both CAU‐23 and MIL‐53‐TDC have the same 2,5‐thiophenedicarboxylate ligand, this shift is due to the different crystal structures [30,40,45] …”

“…[44] In addition to neat CAU-23, mixed-linker materials of the MOFs CAU-23 and MIL-160 have been investigated. [45] In order to further characterize CAU-23, we report here gas sorption data of Ar, CO 2 , H 2 , CH 4 , SO 2 up to a relative pressure p p 0 À 1 of 1, and high-pressure CO 2 sorption experiments up to 20 bar.…”

Metal‐Organic Frameworks as Sorption Materials for Heat Transformation Processes

“…For example, Schlüsener et al recently investigated a "solid solution" mixed-linker approach for aluminum MOFs. [100,101] Aluminum MOFs are particularly promising for industrial applications because aluminum salts are low cost and readily available starting materials, and their MOFs are rather hydrothermally robust materials which can also be manufactured in an environmentally friendly aqueous and even continuous route. [78,82,83,102,103] Schlüsener et al were able to modulate the hydrophilicity between the two water-stable MOFs CAU-10-H and MIL-160 by varying the proportions of the two (commercially inexpensive) linkers (isophthalic acid and furandicarboxylic acid).…”

“…This was somewhat remarkable as the synthesis of MIL‐53‐TDC was hitherto unknown from purely aqueous synthesis conditions. [ 100 ]…”

“…Comparison of uptake regions and water uptake from MIL‐160, CAU‐23, MIL‐53‐TDC, and the Mixed‐MOF (purple‐blue), containing a near 1:1 mixture of the TDC and FDC linker. [ 100 ] Reproduced from ref. [ 80 ] © (2019), with permission from the Royal Society of Chemistry.…”