Metal−organic frameworks (MOFs) are some of the most interesting and promising candidates to sequester toxic H 2 S and SO 2 gases. MOFs show interesting advantages over classic porous materials due to their chemical composition, ligand functionality, cavity dimensions, ease of preparation, and relatively low cost reactivation. The optimization of the physical−chemical interactions between MOFs and H 2 S and SO 2 molecules is the key to further amplification of their capture. Reversibility after the adsorption of H 2 S and SO 2 can be modulated through noncovalent bonding between functionalized ligands (within MOF structures) and H 2 S and SO 2 . This review aims to summarize recent advances in the development of MOF-based systems for the capture and removal of H 2 S and SO 2 . We anticipate that this review article can offer very useful information on the significant and rapid progress of the enhancement of H 2 S and SO 2 capture by MOFs.

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Metal−organic frameworks MIL-53(Al)-TDC and MIL-53(Al)-BDC were explored in the SO 2 adsorption process. MIL-53(Al)-TDC was shown to behave as a rigid-like material upon SO 2 adsorption. On the other hand, MIL-53(Al)-BDC exhibits guest-induced flexibility of the framework with the presence of multiple steps in the SO 2 adsorption isotherm that was related through molecular simulations to the existence of three different pore opening phases narrow pore, intermediate pore, and large pore. Both materials proved to be exceptional candidates for SO 2 capture, even under wet conditions, with excellent SO 2 adsorption, good cycling, chemical stability, and easy regeneration. Further, we propose MIL-53(Al)-TDC and MIL-53(A)-BDC of potential interest for SO 2 sensing and SO 2 storage/transportation, respectively.

An unprecedented reversible guest-induced metallinker bond rearrangement in metal−organic framework (MOFs) was revealed by quantum-calculations and DRIFT experiments. As a showcase, the prototypical MOF-type MFM-300(Sc) was demonstrated to undergo a substantial Sc-carboxylate bond dynamics upon ammonia adsorption to enable a strong metal− guest binding mode, a key feature to ensure a highly efficient capture of this toxic molecule. Decisively, we evidenced this adsorption mechanism to be fully reversible, preserving the ammonia capture performance and structure integrity over multiple cycles. Such an unconventional mechanism in MOFs can open up new avenues to design novel materials for an efficient capture of highly corrosive molecules.

Upon the removal of coordinated H2O and DMF molecules to the paddlewheel of MOP 4 (followed by FTIR), it showed very interesting CO2 capture properties at 196 K.

MFM-300(Sc) was explored as a catalyst for the gas-phase hydrogenation of acetone. The catalysis results support the presence of non-permanent open Sc(III) sites within the structure due to the requirement...

The facile and green preparation of novel materials that capture sulfur dioxide (SO2) with significant uptake at room temperature remains challenging, but it is crucial for public health and the environment. Herein, we explored for the first time the SO2 adsorption within microporous metal–organic cages using the palladium­(II)-based [ Pd6L8] ( NO 3 ) 36 tetragonal prism 1, assembled in water under mild conditions. Notably and despite the low BET surface area of 1 (111 m2 g–1), sulfur dioxide was found to be irreversibly and strongly adsorbed within the activated cage at 298 K (up to 6.07 mmol g–1). The measured values for the molar enthalpy of adsorption (ΔH ads) coupled to the FTIR analyses imply a chemisorption process that involves the direct interaction of SO2 with Pd­(II) sites and the subsequent oxidation of this toxic chemical by the action of the nitrate anions in 1. To the best of our knowledge, this is the first reported metal–organic cage that proves useful for SO2 adsorption. Metallosupramolecular adsorbents such as 1 could enable new detection applications and suggest that the integration of soft metal ions and self-assembly of molecular cages are a potential means for the easy tuning of SO2 adsorption capabilities and behavior.

The chemical transformation of H 2 S inside the micropores of metal−organic frameworks (MOFs) to generate, in situ, polysulfides is an exciting novel strategy for the permanent sequestration of toxic H 2 S with promising implications for the design of novel sulfur battery electrodes. Herein, we discuss how this unexpected MOF-catalyzed polysulfide formation involves mechanisms that diverge radically from conventional coordination chemistry in MOFs. Long-held assumptions that MOF metallinker bonds are rigid and static must be challenged to explain catalysis at MOF metal nodes that nominally lack open metal sites. Instead, this perspective highlights the importance of dynamic metal-linker bonding in designing future MOF catalysts. Embracing the long-overlooked hemilabile coordination chemistry of MOF nodes will inspire explorations into fundamentally new landscapes of heterogeneous reactivity.