Functionalized Ruthenium–Phosphine Metal–Organic Framework for Continuous Vapor-Phase Dehydrogenation of Formic Acid

Abstract

Metal–organic frameworks (MOFs) are ideal hosts for incorporation of molecular complexes without altering their original ligand environment; molecular catalysts can thus be easily synthesized and used in gas- and vapor-phase reactions operated in continuous mode. We report the immobilization of a molecular ruthenium complex in a phosphine-functionalized MOF that is highly efficient in the vapor-phase dehydrogenation of formic acid. The catalyst exhibited exclusive selectivity to hydrogen and carbon dioxide with outstanding stability at 145 °C (TON > 1 290 000). Our results represent a noteworthy improvement over heterogeneous ruthenium systems in terms of selectivity in the gas-phase, while reaching a productivity level higher than that of state-of-the-art homogeneous catalysts.

Metal-organic frameworks as kinetic modulators for branched selectivity in hydroformylation

“…Further evidence that no electronic interaction is responsible for the selectivity change was provided by preparing MOFs that feature strong coordinative bonds with Co such as phosphine MOFs (P-MOFs) 15,[36][37][38] . Such phosphine solid ligands can coordinate Co as supported by the literature 39 and by our DFT P-Co binding energies ( Supplementary Table 15 and Suplementary Fig.…”

“…The chemical flexibility, tuneable pore size and chemical and structural stability of MOFs showed how they can be used to design active sites at the molecular level to direct selectivity and performance of reactions [6][7][8][9][10][11][12] . In recent years, promising catalytic applications that use MOFs as precursors for novel materials 13 as well as model systems to understand heterogeneous catalysis processes have been described 14,15 . After several decades, the field of catalysis by MOFs is still in its infancy since most of the examples are proof of concepts and do not offer attractive advantages to existing catalysts 1,16 .…”

Mixed-linker UiO-66: structure–property relationships revealed by a combination of high-resolution powder X-ray diffraction and density functional theory calculations

“…7,8 In some cases, new properties can emerge from the concomitant presence of two or more functionalities exposed inside the pores, which can be especially useful in selective gas sorption and separation 9,10 or catalysis. [11][12][13][14][15] MIXMOFs based on several topologies have been obtained, notably MOF-5, 7,12,[16][17][18][19] MIL-53, [20][21][22] MIL-101, 17,23,24 DMOF-1, 25,26 UiO-66 [27][28][29][30] and ZIF-8. [31][32][33] Most MIXMOFs are regarded as homogeneous solid solutions, with the linkers randomly distributed throughout the framework, rather than being segregated in phasepure domains.…”

Photocatalyzed Hydrogen Evolution from Water by a Composite Catalyst of NH2‐MIL‐125(Ti) and Surface Nickel(II) Species

“…Metal–organic frameworks (MOFs) assembled from metal–oxygen clusters and organic linkers are widely known for their large internal surface area and propensity for reversible uptake of small molecules . MOFs have found application in environmentally significant catalytic processes such as formic acid dehydrogenation, photocatalyzed carbon dioxide reduction, and organic transformations, as well as water oxidation and reduction . NH 2 ‐MIL‐125(Ti), constructed from Ti 8 O 8 clusters and light‐absorbing aminoterephthalic acid linkers (with 350 and 550 nm absorption maxima) generated 500 μmol of H 2 g(catalyst) −1 after 3 h of visible light irradiation (500 W).…”