Nanoconfinement‐Steered Molecular Preorganization Enables Efficient Monoethanolamine Degradation through Electronically Modulated High‐Valent Iron–Oxo Pathways

While nanoconfinement effectively stabilizes ultrasmall metal nanoparticles to enhance peroxymonosulfate (PMS) activation in Fenton-like systems, precise control over reaction pathways remains challenging. To address this, ultrasmall UiO-66─ZrFe nanoparticles within a π-electron-enriched asymmetric graphene aerogel (GA) are immobilized. This designed confinement architecture not only redirects PMS-activated monoethanolamine (MEA) degradation from nonselective radical oxidation to a dominant high-valent iron-oxo (Fe(IV)═O) pathway but, more importantly, enables a synergistic mechanism coupling molecular preorganization with proton-electron coregulation. Specifically, spatial constraints within UiO-66─ZrFe cages enable MEA to orient its amino group (─NH₂) toward Fe(IV)═O species. This configuration promotes electrophilic attack by Fe(IV)═O on the lone-pair electrons in ─NH₂, simultaneously triggering intramolecular C─N bond cleavage with concomitant proton release. Liberated protons are electrostatically stabilized on the π-conjugated GA network, establishing synergistic coupling with Fe─PMS coordination. This interfacial synergy facilitates directional electron transfer from Fe sites to the carbon matrix and results in regioselective catalysis, enhancing MEA degradation kinetics by 4.85-fold. Practical viability for wastewater remediation is confirmed through life cycle assessment and extended operation. This strategy establishes a generalized design principle for precise reaction control via the orchestration of coupled spatial and electronic effects within engineered microenvironments.