This review article presents the fundamental and practical aspects of water adsorption in Metal-Organic Frameworks (MOFs). The state of the art of MOF stability in water, a crucial issue to many applications in which MOFs are promising candidates, is discussed here. Stability in both gaseous (such as humid gases) and aqueous media is considered. By considering a non-exhaustive yet representative set of MOFs, the different mechanisms of water adsorption in this class of materials are presented: reversible and continuous pore filling, irreversible and discontinuous pore filling through capillary condensation, and irreversibility arising from the flexibility and possible structural modifications of the host material. Water adsorption properties of more than 60 MOF samples are reported. The applications of MOFs as materials for heat-pumps and adsorbent-based chillers and proton conductors are also reviewed. Some directions for future work are suggested as concluding remarks.

Light‐harvesting MOFs: A new porous porphyrinic metal–organic framework (MOF; see picture) was obtained by hydrothermal synthesis. The chemical and thermal stability of the material allows a postsynthetic insertion of zinc in the center of the porphyrin. The visible‐light photocatalytic activity of this porphyrin‐based material is shown for the sacrificial hydrogen evolution from water.

A new porous FeIII‐based MOF, formulated Fe(OH)(BDC)·(dmf)x with x ≈ 1.1 and presenting the MIL‐68 topology, was prepared by reaction of an iron(III) salt and terephthalic acid (H2BDC) in N,N′‐dimethylformamide (dmf) under acidic conditions. The structure and properties of this solid were studied by means of X‐ray diffraction, thermogravimetric analysis, nitrogen sorption, 57Fe Mössbauer spectrometry, and electrochemical lithium insertion.

Lichtsammelnde MOFs: Ein neues Porphyrin‐haltiges Metall‐organisches Gerüst (MOF; siehe Bild) wurde durch Hydrothermalsynthese erhalten. Die chemische und thermische Stabilität des Materials ermöglicht es, Zink nachträglich in das Porphyrin‐Zentrum einzuführen. Die photokatalytische Aktivität dieses Porphyrin‐basierten Materials im sichtbaren Bereich wird anhand der Entwicklung von Wasserstoff aus Wasser gezeigt.

The first structure of a luminescent gold thiolate coordination polymer, [Au(SPh)]n.

Low mechanical pressure on amorphous gold thiolate coordination polymers allows the formation of transparent and red emissive glasses.

An unprecedented efficiency of upconversion is observed in a nonanuclear Yb8Tb complex with green emission upon NIR excitation of Yb.

The first structure elucidation of a lamellar gold thiolate coordination polymer is described. [Au(p-SPhCO2Me)]n is obtained from the simultaneous esterification of mercaptobenzoic acid and reduction of the Au(iii) precursor. Despite the presence of aurophilic interactions, the intense phosphorescence (QY ∼ 70%) originates from intra-ligand and metal-to-ligand transitions.