Li-S rechargeable batteries are attractive for electric transportation because of their low cost, environmentally friendliness, and superior energy density. However, the Li-S system has yet to conquer the marketplace, owing to its drawbacks, namely, soluble polysulfide formation. To tackle this issue, we present here a strategy based on the use of a mesoporous chromium trimesate metal-organic framework (MOF) named MIL-100(Cr) as host material for sulfur impregnation. Electrodes containing sulfur impregnated within the pores of the MOF were found to show a marked increase in the capacity retention of Li-S cathodes. Complementary transmission electron microscopy and X-ray photoelectron spectroscopy measurements demonstrated the reversible capture and release of the polysulfides by the pores of MOF during cycling and evidenced a weak binding between the polysulphides and the oxygenated framework. Such an approach was generalized to other mesoporous oxide structures, such as mesoporous silica, for instance SBA-15, having the same positive effect as the MOF on the capacity retention of Li-S cells. Besides pore sizes, the surface activity of the mesoporous additives, as observed for the MOF, appears to also have a pronounced effect on enhancing the cycle performance. Increased knowledge about the interface between polysulfide species and oxide surfaces could lead to novel approaches in the design and fabrication of long cycle life S electrodes.

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Zeolite-like metal-organic frameworks (ZMOFs) are anionic, have readily exchangeable extra-framework cations, and can be constructed with a variety of organic linkers. ZMOFs therefore can be regarded as an excellent platform for systematic studies of the effect(s) of various structural factors on H(2) binding/interaction with porous metal-organic materials. We find that the enhanced binding of molecular hydrogen in ion-exchanged ZMOFs with an anionic framework is largely governed by the presence of the electrostatic field in the cavity, which is reflected by isosteric heats of adsorption in these compounds which are greater by as much as 50% relative to those in neutral MOFs. Direct contact of the sorbed hydrogen with the exchangeable cations is shown not to be possible in the explored systems thus far, as they retain their form as aqua complexes.

The synthesis of the commercially available aluminum fumarate sample A520 has been optimized and its structure analyzed through a combination of powder diffraction, solid-state NMR spectroscopy, molecular simulation, IR spectroscopy, and thermal analysis. A520 is an analogue of the MIL-53(Al)-BDC solid, but with a more rigid behavior. The differences between the commercial and the optimized samples in terms of defects have been investigated by in situ IR spectroscopy and correlated to their catalytic activity for ethanol dehydration.

The energy-storage capacities of a series of water-stable porous metal-organic frameworks, based on high-valence metal cations (Al , Fe , Cr , Ti , Zr ) and polycarboxylate linkers, were evaluated under the typical conditions of seasonal energy-storage devices. The results showed that the microporous hydrophilic Al-dicarboxylate MIL-160(Al) exhibited one of the best performances. To assess the properties of this material for space-heating applications on a laboratory pilot scale with an open reactor, a new synthetic route involving safer, greener conditions was developed. This led to the production of MIL-160(Al) on a 400 g scale, before the material was shaped into pellets through a wet-granulation method. The material exhibited a very high energy-storage capacity for a physical-sorption material (343 Wh kg ), which is in full agreement with the predicted value.

Porous titanium oxide materials are attractive for energy-related applications. However, many suffer from poor stability and crystallinity. Here we present a robust nanoporous metal–organic framework (MOF), comprising a Ti12O15 oxocluster and a tetracarboxylate ligand, achieved through a scalable synthesis. This material undergoes an unusual irreversible thermally induced phase transformation that generates a highly crystalline porous product with an infinite inorganic moiety of a very high condensation degree. Preliminary photophysical experiments indicate that the product after phase transformation exhibits photoconductive behavior, highlighting the impact of inorganic unit dimensionality on the alteration of physical properties. Introduction of a conductive polymer into its pores leads to a significant increase of the charge separation lifetime under irradiation. Additionally, the inorganic unit of this Ti-MOF can be easily modified via doping with other metal elements. The combined advantages of this compound make it a promising functional scaffold for practical applications.

The water stable UiO-66(Zr)-(CO2H)2 MOF exhibits a superprotonic conductivity of 2.3×10(-3)  S cm(-1) at 90 °C and 95 % relative humidity. Quasi-elastic neutron scattering measurements combined with aMS-EVB3 molecular dynamics simulations were able to probe individually the dynamics of both confined protons and water molecules and to further reveal that the proton transport is assisted by the formation of a hydrogen-bonded water network that spans from the tetrahedral to the octahedral cages of this MOF. This is the first joint experimental/modeling study that unambiguously elucidates the proton-conduction mechanism at the molecular level in a highly conductive MOF.

The exceptional nature of the rht‐MOF platform, based on a singular edge‐transitive net (the only net for the combination of 3‐ and 24‐connected nodes), makes it an ideal target in crystal chemistry. The high level of control indicates an unparalleled blueprint for isoreticular functional materials (without concern for interpenetration) for targeted applications.