Beyond Adsorption: MOFs as Advanced Catalytic Platforms for the Degradation of Aquatic Pollutants
Goshu BS
Published on: 2025-10-31
Abstract
Metal-organic frameworks (MOFs) have emerged as versatile catalysts for advanced oxidation processes (AOPs) in environmental remediation, addressing persistent pollutants like pharmaceuticals, dyes, PFAS, and pesticides. This study synthesizes UiO-66-Zr via solvothermal methods, achieving a BET surface area of 1,200 m²/g and hierarchical porosity for enhanced mass transfer. Photocatalytic degradation under AM 1.5G irradiation yielded 95% methylene blue removal in 60 min, outperforming TiO? by 30%, via metal-to-ligand charge transfer (MLCT) with a 3.2 eV bandgap and 150 ps exciton lifetime. Fenton-like cycles with H?O? (10 mM) catalyzed 98% tetracycline degradation at pH 3.5, with •OH yields 2.5-fold higher than homogeneous systems, supported by continuous Fe²?/Fe³? regeneration. Persulfate activation generated SO?•? for 91% sulfamethoxazole removal, emphasizing non-radical ¹O? pathways. Comparative analysis across MIL, ZIF, and UiO series ranked UiO highest (79.5% average efficiency), excelling in heavy metals (83.2%) and pesticides (82.0%), while MIL led in pharmaceuticals (85.8%) and dyes (86.8%). Engineering strategies, post-synthetic modification (33% activity boost), composites (76.7% stability gain, 13.2 cycles), defect engineering (42.5% activity, low cost), and hybrids (53.8% activity), mitigated limitations, with defect approaches offering optimal ROI (38.6). Stability challenges in real matrices, including fouling (impact 8/10) and ion interference, reduced activity 50-70%, but engineered variants extended lifespans 3-fold. Scalability bottlenecks (TRL 3-4) like batch consistency (urgency 8/10) project 2-4 year resolutions via continuous flows. Environmental risks (HQ=2.8) highlight metal leaching (9/10) and nanoparticle release, with LCA revealing GWP=120 kg CO? eq/kg. A regulatory roadmap forecasts 80% compliance by 2028. These findings advocate tailored UiO-MOFs for sustainable AOPs, bridging lab efficacy with industrial resilience.
Keywords
Metal-organic frameworks; Advanced oxidation processes; Photocatalytic degradation; Stability engineering; Environmental risk assessmentIntroduction
Fundamental Mechanisms of MOF-Mediated Catalysis
The transition of metal-organic frameworks (MOFs) from passive adsorbents to dynamic catalytic platforms represents a paradigm shift in their application for water remediation. While their high surface area facilitates the concentration of pollutants near reactive sites—a phenomenon known as the "concentration effect", their true catalytic prowess stems from their intrinsic structural components and their ability to participate in and catalyze a diverse array of chemical reactions [1]. This section delineates the fundamental mechanisms underpinning MOF-mediated catalysis, with a primary objective of establishing a structure-property-function relationship. We will achieve this by first deconstructing the roles of the primary active sites, the metal nodes and organic linkers, and then elucidating the principal catalytic pathways, including advanced oxidation processes, photocatalysis, and Fenton-like reactions, through which these frameworks degrade aquatic pollutants.
For more to read please go throgh this link: https://www.pubtexto.com/pdf/?beyond-adsorption-mofs-as-advanced-catalytic-platforms-for-the-degradation-of-aquatic-pollutants