Hierarchical ultrathin layered MoS2@NiFe2O4 nanohybrids as a bifunctional catalyst for highly efficient oxygen evolution and organic pollutant degradation

Periodate activation for tetracycline degradation with MoS2/MnFe2O4 nanocomposite: Efficiency and Mechanistic insights

In this study, a MoS2/MnFe2O4 nanocomposite was employed as a periodate (PI) activator for the first time, aiming to synergistically degrade tetracycline (TC). Three different ratios of MoS2/MnFe2O4 nanocomposites were synthesized using a solvothermal method, among which MoS2/MnFe2O4-3 (MMF-3) exhibited the highest efficiency in TC degradation. At pH 4.65, PI concentration of 0.2 mM and MMF-3 dosage of 0.2 g/L, the removal rate of TC was 80.74 %. The potential reaction mechanism of the MMF-3/PI system was revealed, identifying IO•3, 1O2, and •OH as the primary reactive oxygen species (ROS) responsible for TC removal. Furthermore, the Mo(IV)/Mo(VI) cycle within the MoS2/MnFe2O4 composite significantly enhanced the Fe(II)/Fe(III) redox cycle, promoting ROS regeneration and thereby enabling the efficient degradation of TC. Two potential pathways for TC degradation were proposed, and the biotoxicity of the degradation process was assessed, demonstrating that the MMF-3/PI system is environmentally friendly and does not produce highly toxic byproducts. Additionally, Cl- and NO3- showed negligible effects on TC removal, while H2PO4- significantly inhibited the process, and humic acid enhanced it. Cycling experiments revealed consistent TC removal rates exceeding 70 % across four cycles, highlighting the stability and reusability of the MMF-3 material. The removal efficiency of TC was largely unaffected by various natural water conditions, underscoring the substantial practical potential of the MMF-3/PI system. Overall, the MMF-3/PI system offers a promising approach to mitigating antibiotic contamination in water bodies.

Floatable and magnetic MoS2/NiFe2O4/chitosan nanocomposite integrated melamine sponges with hybrid photothermal and photocatalytic enhancement for pollutant removal

Magnetic chitosan-based materials with good adsorption-photocatalysis and magnetic properties have great prospect in wastewater treatment. In this paper, a floating magnetic molybdenum disulfide/NiFe2O4/chitosan integrated melamine sponges (m-MoS2/CS@MS) was fabricated using chitosan as absorbent and adhesive, MoS2 and NiFe2O4 as photocatalysts, and melamine sponge as support material. The m-MoS2/CS@MS has a rich light-water-air-material interaction interface and can float on the water surface. The light absorbance of m-MoS2/CS@MS had dramatically increased by 55.77 % with the introduction of MoS2 and NiFe2O4 nanoparticles. The m-MoS2/CS@MS can effectively remove Congo red dye at pH = 2-10 under different coexisting inorganic salts (Cl-, SO42-) and water matrices (ultrapure water, tap water, Lake water, and mineral water). The m-MoS2/CS@MS had excellent photocatalytic degradation ability, reaching a degradation rate of 98.88 % under simulated solar light irradiation. Furthermore, the m-MoS2/CS@MS composite exhibited excellent stability, convenient magnetic recycling performance, reusability and its suitability for dye wastewater treatment under different conditions. This research provided a new insight into the practical application of sustainable and clean chitosan-based materials.

MnFe2O4/MoS2 catalyst used for ozonation: optimization and mechanism analysis of phenolic wastewater treatment

The performance of catalytic ability of MFe2O4/MoS2 in the ozonation process was investigated in this work. The synthesized MnFe2O4/MoS2 was optimize prepared and then characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photo-electron spectroscopy, and magnetic saturation strength. The results showed that when Cphenol = 200 mg/L, initial pH = 9.0, Q = 0.10 L/min, and CMnFe2O4/MoS2 = 0.10 g/L, MnFe2O4/MoS2 addition improved the degradation efficiency of phenol by 20.0%. The effects of pH, catalyst dosage, and inorganic ions on the phenol removal by the MnFe2O4/MoS2 catalytic ozonation were investigated. Five cycle experiments proved that MnFe2O4/MoS2 had good recyclability and stability. MnFe2O4/MoS2 also showed good catalytic performance in the treatment of coal chemical wastewater pesticide wastewater. The MnFe2O4 doped with MoS2 could provide abundant surface active sites for ozone and promote the stable cycle of Mn2+/Mn3+and Fe2+/Fe3+, thus generating large amounts of •OH and improving the degradation of phenol by ozonation. The MnFe2O4/MoS2/ozonation treatment system provides a technical reference and theoretical basis for industrial wastewater treatment.

A molybdenum disulfide/nickel ferrite-modified voltammetric sensing platform for ultra-sensitive determination of clenbuterol under the presence of an external magnetic field†

The electrochemical behavior and sensing performance of an electrode modified with NiFe₂O₄ (NFO), MoS₂, and MoS₂–NFO were thoroughly investigated using CV, EIS, DPV, and CA measurements, respectively. MoS₂–NFO/SPE provided a higher sensing performance towards the detection of clenbuterol (CLB) than other proposed electrodes. After optimization of pH and accumulation time, the current response recorded at MoS₂–NFO/SPE linearly increased with an increase of CLB concentration in the range from 1 to 50 μM, corresponding to a LOD of 0.471 μM. In the presence of an external magnetic field, there were positive impacts not only on mass transfer, ionic/charge diffusion, and absorption capacity but also on the electrocatalytic ability for redox reactions of CLB. As a result, the linear range was widened to 0.5–50 μM and the LOD value was about 0.161 μM. Furthermore, stability, repeatability, and selectivity were assessed, emphasizing their high practical applicability.

The electrochemical behavior and sensing performance of an electrode modified with NiFe₂O₄ (NFO), MoS₂, and MoS₂–NFO were thoroughly investigated using CV, EIS, DPV, and CA measurements, respectively.

Molybdenum Disulfide-Based Nanomaterials for Visible-Light-Induced Photocatalysis

Visible-light-responsive photocatalytic materials have a multitude of important applications, ranging from energy conversion and storage to industrial waste treatment. Molybdenum disulfide (MoS₂) and its variants exhibit high photocatalytic activity under irradiation by visible light as well as good stability and recyclability, which are desirable for all photocatalytic applications. MoS₂-based materials have been widely applied in various fields such as wastewater treatment, environmental remediation, and organic transformation reactions because of their excellent physicochemical properties. The present review focuses on the fundamental properties of MoS₂, recent developments and remaining challenges, and key strategies for tackling issues related to the utilization of MoS₂ in photocatalysis. The application of MoS₂-based materials in visible-light-induced catalytic reactions for the treatment of diverse kinds of pollutants including industrial, environmental, pharmaceutical, and agricultural waste are also critically discussed. The review concludes by highlighting the prospects of MoS₂ for use in various established and emerging areas of photocatalysis.

Three-dimensional porous MoS2 nanobox embedded g-C3N4@TiO2 architecture for highly efficient photocatalytic degradation of organic pollutant

Herein, a simple, highly efficient and stable MoS₂ nanobox embedded graphitic-C₃N₄@TiO₂ (g-CN@TiO₂) nanoarchitecture was synthesized by a facile solvothermal approach. The nano-hybrid photocatalyst was constructed by TiO₂ nanoparticles anchored on the surface of g-CN nanosheets. Then highly crystalline three-dimensional porous MoS₂ nanobox was homogeneously distributed on the g-CN@TiO₂ surface. The g-CN@TiO₂/MoS₂ hybrid achieved a high photocatalytic degradation efficiency of 97.5% for methylene blue (MB) dye pollutant under visible-light irradiant in an hour which was much better than TiO₂@MoS_2, g-CN@TiO_2, MoS_2, TiO₂ and g-CN. Furthermore, the reaction rate (k) value of g-CN@TiO₂/MoS₂ for MB dye is as high as 3.18 X 10^-2 min^-1, which is ~ 2.65 times better than those of g-CN@TiO₂ and MoS₂. This work presents a rational structure design, interfacial construction and suitable band gap strategy to synthesize advanced nano-hybrid photocatalyst for degradation of organic pollutant with excellent performance and long-term stability.