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Herein, we synthesized CoS 2 /MoS 2 catalysts with vertical interface structures to enhance peroxymonosulfate (PMS) activation. The characterization, experimental, and calculation results jointly reveal that the strong interface interaction (Co−S−Mo bond) regulates the electronic structure of CoS 2 /MoS 2 to optimize the generation process of the main reactive oxygen species (SO 4 •−) and stabilizes the coordination structure of the active sites to greatly improve catalytic robustness. The unique interface structure of CoS 2 /MoS 2 constructs the confined nanoreactor to adsorb pollutants and capture pollutant electrons,whcih can shorten the migration distance of SO 4 •− and improve the electron transfer rate, ultimately increasing the utilization and conversion rate of PMS. CoS 2 /MoS 2 achieved outstanding activity (0.302 min−1), stability (93% of reactivity maintained after eight runs), and acid-base resistance (working pH range 3–11) for sulfamethazine degradation. This work provides a clear perspective for the rational design and optimization of interface engineering-mediated dual component catalysts in the Fenton-like reactions. [Display omitted] • Confined CoS 2 /MoS 2 nanoreactors with interface Co-S-Mo bond was fabricated. • Interface electronic reconfiguration boosted the PMS activation process. • Pollutants enriched in nanoreactors and acted as electron donors to improve the PMS utilization and conversion. • CoS 2 /MoS 2 /PMS system exhibited strong resistance to inorganic ions and pH value. [ABSTRACT FROM AUTHOR]

Singlet oxygen (1O 2) plays a crucial role in Fenton-like reactions due to its high efficiency and selectivity in removing trace organic pollutants from complex water matrices. Defect engineering, which allows the efficient exposure of active sites and optimization of electronic structures, has rapidly emerged as a fundamental strategy for enhancing 1O 2 yield. Herein, we introduce tunable sulfur vacancy (V S) density into Co 9 S 8 catalysts for peroxymonosulfate (PMS) activation. The modulation of the octahedral Co (CoS 6) and tetrahedral Co (CoS 4) electronic structures by V S triggers the unexpected selective generation of 1O 2. The V S /PMS system exhibits excellent resistance to interference and highly selective degradation of electron-donating organic pollutants. Experimental and theoretical calculations revealed a new evolutionary route for 1O 2 involving two phases (Phase I: HSO 5 − → *O, Phase II: *O + HSO 5 − →*OO → 1O 2). This study provides a molecular-level understanding of V S -mediated catalytic selectivity for high-efficient decontamination applications. [Display omitted] • Co 9 S 8 catalysts with tunable V S was fabricated to PMS activation for contaminants degradation. • The optimized V S /PMS system achieved 1O 2 -dominated degradation mechanism. • Regulation d-band center of Co-3d orbital boosted the process of HSO 5 − adsorption and activation. • Combining experiment and DFT results revealed a new evolutionary route of 1O 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • Construction hollow-shell CoS/CN catalyst derived from the ZIF-67 precursor. • CoS/CN + PMS system achieved efficient sulfonamide degradation. • Electron transfer acceleration was achieved by the synergistic effect of S2− and g-C 3 N 4. • 1O 2 was identified as the primary reactive oxygen species in the degradation process. • A new evolutionary route for the generation of 1O 2 was proposed. Sulfanilamide (SM), which is a representative drug of sulfonamides, is commonly used for the prevention and treatment of bacterial infectious diseases and is extremely difficult to remove from water. Herein, an efficient catalyst (CoS/CN) for sulfanilamide degradation was constructed by CoS self-assembling on ultrathin graphitic carbon nitride (g-C 3 N 4) nanosheets. The prepared hollow-shell CoS/CN catalyst could completely degrade SM within 10 min with a rate constant of 2.49 min−1 through the activation of peroxymonosulfate (PMS). Experiments and theoretical calculations indicated that S2− acted as an electron donor for promoting the generation of Co(II). The combination of g-C 3 N 4 and CoS made the CoS/CN composite have higher conductivity and electron transfer ability than CoS, which promoted the decomposition of PMS to produce reactive oxygen species (ROSs). Singlet oxygen (1O 2) was proved as the primary ROSs, and SO 4 − radicals were generated during the 1O 2 -dominated degradation process to improve the low mineralization rate. 1O 2 and SO 4 − were derived from the oxidation of PMS and the electron transfer of g-C 3 N 4. The results revealed the synergistic effect of free radicals and non-free radicals during the redox of PMS, and provided theoretical support for the efficient degradation of refractory organics in wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • The core–shell magnetic CoFe-CoFe 2 O 4 @N-C catalyst with dual sites was constructed. • The pyrrolic N on the shell of catalyst was an "adsorption trap" for ofloxacin. • The encapsulated CoFe 2 O 4 was catalytic site for peroxymonosulfate (PMS) activation. • The dual sites shortened the migration distance between radicals and ofloxacin. • CoFe-CoFe 2 O 4 @N-C/PMS system achieved efficient ofloxacin degradation. The rational design and construction of bifunctional catalysts with excellent adsorption and catalytic activity are meaningful but challenging. Herein, a core–shell magnetic CoFe-CoFe 2 O 4 @N-C catalyst with dual sites was constructed to shorten the migration distance between the target contaminant of ofloxacin (OFX), a typical antibiotic, and reactive oxygen species (ROS) in Fenton-like degradation. The characterization results and theory calculations indicated that abundant pyrrolic N sites on shells served as "adsorption traps" for OFX and encapsulated CoFe 2 O 4 as activation sites for peroxymonosulfate (PMS). The unique reaction pathway between in-situ generated ROS and adjacent adsorbed OFX enhanced the catalytic ability, showing 100% removal of OFX (20 mg/L) with a high rate constant (0.422 min−1). Meanwhile, the system presented excellent anti-interference capability to inorganic (Cl–, NO 3 –, and H 2 PO 4 –), organic (humic acid), actual aqueous matrices (tap water and river water), and good stability proved by the continuous flow experiment. The work will provide ideas for designing bifunctional catalysts and supply an eco-friendly process for boosting in-situ Fenton-like degradation. [ABSTRACT FROM AUTHOR]