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Tetracycline is an organic compound that poses a significant threat to both the ecological environment and human health during its long-term production and use. Advanced oxidation processes based on sulfate radicals (SR-AOP) have been recognized as effective techniques for treating antibiotic contamination. However, The urgent demand for a green, efficient, and recyclable catalyst to effectively facilitate persulfate treatment of tetracycline pollution is evident. Magnetic Fe 3 O 4 -C@MoS 2 composite were synthesized using hydrothermal and pyrolysis methods. Degradation experiments, free radical quenching experiments, EPR analysis were carried out to investigate the degradation performance and mechanisms of Fe 3 O 4 -C@MoS 2 composite. Results showed that the degradation efficiency of 100 mL of 20 mg/L tetracycline solution reached up to 97% within 40 mins with the dosage of 20 mg Fe 3 O 4 -C@MoS 2 and 30.7 mg peroxmonosulfate. Furthermore, this degradation system exhibited excellent efficiency even over a wide pH range of 3–9. The transformation of Mo (IV) and S2-/S n 2- species valence states facilitated the conversion between Fe(III)/Fe(II). Both free radical (S O 4 ⋅ − , ⋅ O H and O 2 ⋅ −) as well as non-free radical species (O 2 1) were found to accelerate the catalytic reaction during the tetracycline degradation. The possible pathways of tetracycline degradation were proposed, and the toxicity of the intermediate products were proved to be lower than that of tetracycline. Finally, magnetic Fe 3 O 4 -C@MoS 2 composites possessed good reusability and stability after 4 cycles of degradation. [Display omitted] • Fe 3 O 4 -C@MoS 2 -2/PMS achieved 97% of TC degradation efficiency within 40 mins. • Mo (IV) and S2-/S n 2- species promoted the redox cycle of Fe(III)/Fe(II). • Synergistic effects of free radicals (S O 4 ⋅ − , ⋅ O H and O 2 ⋅ −) and non-free radical (O 2 1) species enhanced the high degradation efficiency of TC. • Fe 3 O 4 -C@MoS 2 -2 with magnetism exhibited favorable reusability and stability. [ABSTRACT FROM AUTHOR]

Two-dimensional metal-organic framework nanosheets (2D MONs) are excellent heterogeneous catalysts owing to their high density and accessible catalytic sites, reduced diffusion pathways for reactants/products, and fast electron transport. Moreover, the employment of 2D MONs as supports to encapsulate noble nanoparticles can not only stabilize the noble nanoparticles, but also significantly improve their catalytic activity through the synergetic effect between 2D MONs and noble nanoparticles. Herein, we reported a microwave-assisted method for the rapid preparation of 2D UiO-67 metal-organic framework nanosheets (named UiO-67 NS). The Au nanoparticles modified UiO-67 nanocomposites (denoted as Au/UiO-67 NS nanocomposites) are formed by the in situ reduction of HAuCl 4 in the pores of UiO-67 NS. The Au/UiO-67 NS nanocomposites show excellent catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol, and only 20 equivalent sodium borohydride can completely reduce 10 mM 4-NP in 100 s, thanks to highly exposed Au NPs and reduced diffusion distance. In addition, XPS characterizations showed that the binding energy of Au 4 f in Au/UiO-67 NS nanocomposites displays a 0.48 eV less than that of Au nanoparticles on UiO-67 octahedral microcrystals (denoted as Au@UiO-67 OM), which is believed to be responsible for the enhanced catalytic activity toward the reduction of 4-nitrophenol. [Display omitted] • Microwave-assisted method allows efficient, rapid and reproducible preparation of 2D Zr-MOFs UiO-67 nanosheets (UiO-67 NS). • In situ reduction of impregnated HAuCl4 by NaBH4 results in highly dispersed and accessible Au nanoparticles on UiO-67 NS. • The Au/UiO-67 NS shows higher catalytic activity than Au nanoparticles decorated UiO-67 octahedral microcrystals. • The reduction products of 4-aminophenol can be further converted into 4-acetoxyacetanilide in one-pot reaction. [ABSTRACT FROM AUTHOR]

• CoMn 2 O 4 @CoMn 2 S 4 nanocomposites were firstly prepared via in-situ growth method. • The specific capacity of the CoMn 2 O 4 @CoMn 2 S 4 reaches 1542.0 C g−1 at 1 A g−1. • The capacity retention of the CoMn 2 O 4 @CoMn 2 S 4 is 95.81% after 5000 cycles at 20 A g−1. • The symmetric capacitor (CoMn 2 O 4 @CoMn 2 S 4 //AC) exhibits excellent performance. In this work, a novel CoMn 2 O 4 @CoMn 2 S 4 core-shell nanocluster@nanosheet was successfully grown onto Ni foam via a hydrothermal reaction, which omitted the addition of a binder and conductive additive and the need for a complicated electrode preparation process. CoMn 2 S 4 nanosheets as "shells" were found to be uniformly distributed on the surface of CoMn 2 O 4 nanoclusters as "cores" to form a typical core-shell structure. These structures possess a high specific surface area and abundant active sites, which not only shorten the transmission path for electrons and ions, but also prevent collapse of the structure, thus improving its cycling stability. The specific capacity of CoMn 2 O 4 @CoMn 2 S 4 is 1542.0 C g−1 at a current density of 1 A g−1, which is 3.1 times higher than that obtained for CoMn 2 O 4. Moreover, CoMn 2 O 4 @CoMn 2 S 4 shows excellent electrochemical cycling performance, and the specific capacity retention rate for CoMn 2 O 4 @CoMn 2 S 4 reaches 95.81% after 5000 cycles at a current density of 20 A g−1. The specific energy of the CoMn 2 O 4 @CoMn 2 S 4 reaches 44.30 Wh kg−1 at a specific power of 774.98 W kg−1. Therefore, the CoMn 2 O 4 @CoMn 2 S 4 //AC device shows excellent practical application capability. [ABSTRACT FROM AUTHOR]

• Rh single atoms were loaded onto the surface of Cu 2 MoS 4 nanoparticles. • The photocatalytic efficiency of the Cu 2 MoS 4 /Rh composites was evaluated. • Rh single atoms could prevent electron/hole recombination during photocatalytic reaction. In this study, hollow cubic Cu 2 MoS 4 nanoparticles were synthesized via a facile hydrothermal method. Following that, Rh single atoms were loaded onto the surface of Cu 2 MoS 4 nanoparticles to prevent electron/hole recombination. The cubic morphology of Cu 2 MoS 4 nanoparticles and the presence of Rh atoms were investigated by Transmitting Electron Microscope (TEM). The crystal structure of the synthesized Rh-loaded Cu 2 MoS 4 was studied by X-ray diffraction (XRD). The shift in Rh X-ray Photoelectron Spectroscopy (XPS) peaks indicated the intimate interaction between Rh and Cu 2 MoS 4 , providing a pathway for the charge transfer. The photocatalytic efficiency of the synthesized photocatalysts was significantly enhanced by introducing Rh single atoms onto the Cu 2 MoS 4 surface. Consecutive photocatalytic dye degradation experiments revealed that Rh-loaded Cu 2 MoS 4 nanoparticles could be recycled and reused multiple times with no drop in the photocatalytic efficiency. The improved photocatalytic performance of Rh-loaded Cu 2 MoS 4 was attributed to a lower charge transfer resistance, higher charge transfer rate, and longer charge carrier lifetime. The most crucial reactive radical was detected to be ⋅O 2 - while e - and h + are also playing an essential role in the photocatalytic degradation of RhB on Rh-loaded Cu 2 MoS 4. This study highlighted the importance of forming a Schottky junction between Rh and Cu 2 MoS 4 to enhance charge carrier separation and improve photocatalytic efficiency. [ABSTRACT FROM AUTHOR]