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1. High-Efficiency Photodynamic Antibacterial Activity of NH ₂ -MIL-101(Fe)@MoS ₂ /ZnO Ternary Composites

   https://doi.org/10.1021/acsabm.2c00439  

   Liu, Junli; Cheng, Wenxia; Zhang, Kaitao; Liu, Hui; Li, Junqi; Tressel, John; Chen, Shaowei (August 2022, ACS Applied Bio Materials)
2. Implications of Defect Density and Polymer Interactions for CO ₂ Capture on Amine‐Functionalized MIL‐101(Cr)

   https://doi.org/10.1002/cssc.202400249  

   Yang, Rachel A.; Cho, Stanley; Hughes, Sydney N.; Sarazen, Michele L. (May 2024, ChemSusChem)

   Abstract Rising anthropogenic carbon emissions have dire environmental consequences, necessitating remediative approaches, which includes use of solid sorbents. Here, aminopolymers (poly(ethylene imine) (PEI) and poly(propylene imine) (PPI)) are supported within solid mesoporous MIL‐101(Cr) to examine effects of support defect density on aminopolymer‐MOF interactions for CO₂uptake and stability during uptake‐regeneration cycles. Using simulated flue gas (10 % CO₂in He), MIL‐101(Cr)‐ρ_high(higher defect density) shows 33 % higher uptake capacity per gram adsorbent than MIL‐101(Cr)‐ρ_low(lower defect density) at 308 K, consistent with increased availability of undercoordinated Cr adsorption sites at missing linker defects. Increasing aminopolymer weight loadings (10–50 wt.%) within MIL‐101(Cr)‐ρ_lowand MIL‐101(Cr)‐ρ_highincreases amine efficiencies and CO₂uptake capacities relative to bare MOFs, though both incur CO₂diffusion limitations through confined, viscous polymer phases at higher (40–50 wt.%) loadings. Benchmarked against SBA‐15, lower polymer packing densities (PPI>PEI), weaker and less abundant van der Waals interactions between aminopolymers and pore walls, and open framework topology increase amine efficiencies. Interactions between amines and Cr defect sites incur amine efficiency losses but grant higher thermal and oxidative stability during uptake‐regeneration cycling. Finally, >25 % higher CO₂uptake capacities are achieved for aminopolymer/MIL‐101(Cr)‐ρ_highunder humid conditions, demonstrating promise for realistic applications. 

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3. Synergistic Enhancement of CO2 Capture via Amine Decorated Hierarchical MIL-101 (Cr)/SBA-15 Composites

   Mukherjee, D; Hassan, S; Shahjahan, J; Prokofjevs, A; Kuila, D (August 2024, System)

   Synthesis of amine incorporated hierarchical metal organic framework (MOF) MIL-101(Cr)/SBA-15, meso/ micro-porous composites, with tailored properties for CO 2 capture is reported. The synthesized composites were characterized in terms of their crystallinity, morphology, functional groups, and textural properties. Isothermal adsorption of CO 2 from concentrated sites as well as ambient conditions were evaluated by gravimetric and volumetric measurements. The optimized composite i.e., MIL-101(Cr)/SBA-15/PEI-25 showed improved pseudo- equilibrium adsorption capacity of 3.2 mmol/g at 303 K and 1 bar, compared to nascent SBA-15 (0.8 mmol/g) and the MOF, i.e., MIL-101(Cr) (1.3 mmol/g). Such adsorption performance can be attributed to the basic sites of the impregnated polyethyleneimine (PEI), unsaturated Cr(III) metal sites, and the hierarchical pore structure of the composite which imparts chemical as well physical adsorption forces towards CO 2 lower amine loading of 25 wt% in the composite resulted in facile CO 2 uptake. Interestingly, desorption at much lower temperature of 

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4. Reaction pathways and deactivation mechanisms of isostructural Cr and Fe MIL-101 during liquid-phase styrene oxidation by hydrogen peroxide

   https://doi.org/10.1039/D1CY00567G  

   Yang, Rachel A.; Sarazen, Michele L. (August 2021, Catalysis Science & Technology)

   Isostructural Cr and Fe nanoporous MIL-101, synthesized without mineralizing agents, are investigated for styrene oxidation utilizing aqueous hydrogen peroxide to yield valuable oxygenates for chemical synthesis applications. Styrene conversion rates and oxygenate product distributions both depend on metal identity, as MIL-101(Fe) is more reactive for total styrene oxidation and is more pathway selective, preferring aldehyde (benzaldehyde) formation at the α-carbon to the aromatic ring, where MIL-101(Cr) sustains epoxide (styrene oxide) production at the same α-carbon. These pathways often involve hydrogen peroxide derived radical intermediates (O, –HOO˙, –HO − ˙) and metallocycle transition states. We postulate that the higher reactivity of one of these surface intermediates, Fe( iv )O relative to Cr( iv )O, leads to higher styrene oxidation rates for MIL-101(Fe), while higher electrophilicity of Cr( iii )–OOH intermediates translates to the higher styrene oxide selectivity observed for MIL-101(Cr). Secondary styrene oxide and benzaldehyde conversions are observed over both analogs, but the former is more prevalent over MIL-101(Fe) due to higher Lewis/Brønsted acid site density and strength compared to MIL-101(Cr). Recyclability experiments combined with characterization via XRD, SEM/EDXS, and FT-IR and UV-vis spectroscopies show that the nature of MIL-101(Fe) sites does not change significantly with each cycle, whereas MIL-101(Cr) suffers from metal leaching, which impacts styrene conversion rates and product distribution. Both catalysts require active site regeneration, though MIL-101(Fe) sites are more susceptible to reactivation, even under mild conditions. Finally, examination of styrene conversion for three unique synthesized phases of MIL-101(Cr) rationalizes that nodal defects are largely responsible for observed reactivity and selectivity but predispose the framework to metal leaching as a predominant deactivation mechanism. 

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5. Mechanistic Insight into Photocatalytic Pathways of MIL-100(Fe)/TiO ₂ Composites

   https://doi.org/10.1021/acsami.9b00223  

   He, Xiang; Fang, Hong; Gosztola, David J.; Jiang, Zhang; Jena, Puru; Wang, Wei-Ning (March 2019, ACS Applied Materials & Interfaces)