Novel Lanthanide(III) Porphyrin-Based Metal–Organic Frameworks: Structure, Gas Adsorption, and Magnetic Properties

Abstract

The present work focuses on the hydrothermal synthesis and properties of porous coordination polymers of metal–porphyrin framework (MPF) type, namely, {[Pr4(H2TPPS)3]·11H2O} n (UPJS-10), {[Eu/Sm­(H2TPPS)]·H3O+·16H2O} n (UPJS-11), and {[Ce4(H2TPPS)3]·11H2O} n (UPJS-12) (H2TPPS = 4,4′,4″,4‴-(porphyrin-5,10,15,20-tetrayl)­tetrakisbenzenesulfonate­(4-)). The compounds were characterized using several analytical techniques: infrared spectroscopy, thermogravimetric measurements, elemental analysis, gas adsorption measurements, and single-crystal structure analysis (SXRD). The results of SXRD revealed a three-dimensional open porous framework containing crossing cavities propagating along all crystallographic axes. Coordination of H2TPPS4– ligands with Ln­(III) ions leads to the formation of 1D polymeric chains propagating along the c crystallographic axis. Argon sorption measurements at −186 °C show that the activated MPFs have apparent BET surface areas of 260 m2 g–1 (UPJS-10) and 230 m2 g–1 (UPJS-12). Carbon dioxide adsorption isotherms at 0 °C show adsorption capacities up to 1 bar of 9.8 wt % for UPJS-10 and 8.6 wt % for UPJS-12. At a temperature of 20 °C, the respective CO2 adsorption capacities decreased to 6.95 and 5.99 wt %, respectively. The magnetic properties of UPJS-10 are characterized by the presence of a close-lying nonmagnetic ground singlet and excited doublet states in the electronic spectrum of Pr­(III) ions. A much larger energy difference was suggested between the two lowest Kramers doublets of Ce­(III) ions in UPJS-12. Finally, the analysis of X-band EPR spectra revealed the presence of radical spins, which were tentatively assigned to be originating from the porphyrin ligands.

Post-synthetically modified metal–porphyrin framework GaTCPP for carbon dioxide adsorption and energy storage in Li–S batteries

“…The high surface area, crystallinity, controllable pore size, exibility, and functionalization of the porous surface are some of the main characteristics which determine the versatility of MOFs. 1 Hence, MOFs are investigated in applications such as gas storage and separation, 2-6 catalysis, [7][8][9] drug delivery, [10][11][12] proton conductivity, [13][14][15] magnetism [16][17][18][19] etc. 20 In our research for discovering novel original porous frameworks with multifunctional linkers, we mainly focused on porphyrinic building blocks.…”

A New Member of the Metal‐Porphyrin Frameworks Family: Structure, Physicochemical Properties, Hydrogen and Carbon Dioxide Adsorption

“…The comparison of the observed BET value with BET areas reported recently for other materials containing H 2 TPPS 4À ligand and lanthanide central atom shows, that UPJS-17 has a lower surface area that e. g. UPJS-10 (259 m 2 g À 1 ) and UPJS-12 (229 m 2 g À 1 ). [20] Carbon dioxide adsorption isotherms on activated compound UPJS-17 were collected at 0, 10, 20, 30 and 40 °C. The isotherms are shown in Figure 4 and corresponding adsorbed amounts of the carbon dioxide are listed in Table 1.…”

Metal-porphyrinic framework nanotechnologies in modern agricultural management

“…Recent examples include [Pr 4 (H 2 TPPS) 3 ·11H 2 O] n and [Ce 4 (H 2 TPPS) 3 ]·11H 2 O] n (H 2 TPPS = 4,4′,4′′,4′′′-(porphyrin-5,10,15,20-tetrayl)tetrakisbenzenesulfonate 4− ). 98 Their magnetic properties were fully described and analysis of the EPR spectra indicated the presence of radical spins, which were tentatively assigned to originate from the porphyrin ligands in one of these two cases.…”