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Advanced strategies for enhancing catalytic performance of catalysts include multi-metal active site exposure, vacancy growth and electronic structure optimization. Here, carbon nanotube-loaded CoSe 2 /FeSe 2 catalysts (Co/Fe-CNT) with multiphase boundaries and embedded selenium vacancies (V Se) were prepared using a one-step hydrothermal method. The catalysts feature unique electronic structures and abundant active sites, and were found to exhibit unexpectedly high activity and stability in photocatalytic mediated sulphate radical (SR-photo) system, with impressive oxidation capacity for complex matrix polluted water. The spontaneously formed internal electric field strongly promoted charge transport and significantly enhanced the photocatalytic property. The V Se formed at the heterogeneous interface could modulate the surface electronic structure and accelerate the redox cycling of transition metals, thereby accelerating the production of reactive oxygen species and boosting the efficiency of contaminant degradation. This work provides guidance for the design of high-performance catalysts for V Se engineering and expands their potential for application in wastewater purification. [Display omitted] • A nanorods embedded with crystal-like Co/Fe-CNT containing heterostructure and selenium vacancies (VSe) was prepared. • 1Co/1Fe-CNT with heterojunction interface exhibited excellent photocatalytic PMS activation for pollutants degradation. • The built-in electric field in Co/Fe-CNT boosted charge separation confirmed by DFT calculation. • The introduction of VSe promoted the redox cycle of transition metals and enhanced the adsorption of PMS on active sites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Stable encapsulated SC@MoS 2 crystal was facilely fabricated by hydrothermal method. • MoS 2 coating facilitated electron transfer and rapidly activated PMS to generate reactive oxygen species. • Oxygen defects and transition metals act as active sites for the activation of PMS. • Feasibility of SC@MoS 2 /PMS system was proved by organic pollutants degradation and reusability. Perovskite oxides and molybdenum sulfide (MoS 2) are both promising catalysts for advanced oxidation processes in environmental pollutant degradation. Herein, a core-shell structure of MoS 2 encapsulating Sr-Co perovskite microcrystalline (SC@MoS 2) was used to activate peroxymonosulfate (PMS) for degradation of organics. Levofloxacin (LVF) degradation by SC@MoS 2 /PMS system was improved obviously, and 0.2-SC@MoS 2 exhibited the optimized activation for PMS with best LVF degradation performance (97%) within 15 min. In the 0.2-SC@MoS 2 /PMS system, the dosage of catalyst was the key determinant of LVF degradation. Simultaneously, 0.2-SC@MoS 2 achieved outstanding reusability and good degradation capacity of different contaminants. The encapsulation of molybdenum disulfide layer facilitated electron transfer between PMS and core-shell structure. According to the EPR analysis and quenching experiments, both radicals (SO 4 − and OH), and nonradical (1O 2) were involved in the degradation of LVF. Under visible light irradiation, O 2 − participated in the reaction and enhanced LVF degradation efficiency, because the valence band and conduction band of components are different. Furthermore, the density functional theory (DFT) calculation, intermediates determination and Toxicity Estimation Software Tool (T.E.S.T) analysis provided meaningful support in the degradation pathways and ecological risks of LVF residues. [ABSTRACT FROM AUTHOR]

[Display omitted] • F pollutants are reused in the preparation of F-doped carbon catalysts. • Uniform F doping is achieved by grafting F fragments onto graphite sheet (GS). • The small size of WO 3 are in-situ synthesized and loaded. • The WO 3 @F-doped GS catalyst shows excellent OER activity and stability. • DFT calculation reveals the synergistic effect of F doping and WO 3 loading on OER. Electrochemical oxygen evolution reaction (OER) is an important anodic semi-reaction for energy storage and conversion. In this work, Perfluorooctanoic acid (PFOA), an aqueous pollutant, is degraded into F-containing fragments and captured to prepare ultrasmall WO 3 decorated F-doped graphite sheets (WO 3 @F-GS) via a plasma-induced assembly method. WO 3 @F 0.1 -GS achieves a low overpotential of 298 mV and Tafel slope of 77.6 mV dec-1, as low as that of RuO 2. Meanwhile, WO 3 @F 0.1 -GS exhibits good stability in both OER and overall water splitting in 1 M KOH. The synergistic effect of WO 3 and F enhances the electrocatalytic performance. Density functional theory calculations prove W4+ coordinates with F-doping resulting in enhanced adsorption of OH– and decreased energy barrier of OH deprotonation, leading good activity. The steric hindrance of F and WO 3 loading hinder the stacking of graphitic layers and improve the stability. This work not only provides a mild synthesis strategy of F-doping, but also provides a novel reutilization approach for fluoride waste. [ABSTRACT FROM AUTHOR]