Synthetic Fabrication of Nanoscale MoS2-Based Transition Metal Sulfides

Interaction of 2D nanomaterial with cellular barrier: Membrane attachment and intracellular trafficking

The cell membrane serves as a barrier against the free entry of foreign substances into the cell. Limited by factors such as solubility and targeting, it is difficult for some drugs to pass through the cell membrane barrier and exert the expected therapeutic effect. Two-dimensional nanomaterial (2D NM) has the advantages of high drug loading capacity, flexible modification, and multimodal combination therapy, making them a novel drug delivery vehicle for drug membrane attachment and intracellular transport. By modulating the surface properties of nanocarriers, it is capable of carrying drugs to break through the cell membrane barrier and achieve precise treatment. In this review, we review the classification of various common 2D NMs, the primary parameters affecting their adhesion to cell membranes, and the uptake mechanisms of intracellular transport. Furthermore, we discuss the therapeutic potential of 2D NMs for several major disorders. We anticipate this review will deepen researchers' understanding of the interaction of 2D NM drug carriers with cell membrane barriers, and provide insights for the subsequent development of novel intelligent nanomaterials capable of intracellular transport.

Study on the Performance of Ni-MoS2 Catalysts with Different MoS2 Structures for Dibenzothiophene Hydrodesulfurization

Hydrodesulfurization (HDS) is an important process for the production of clean fuel oil, and the development of a new environmentally friendly, low-cost sulfided catalyst is key research in hydrogenation technology. Herein, commercial bulk MoS2 and NiCO3·2NiOH2·4H2O were first hydrothermally treated and then calcined in a H2 or N2 atmosphere to obtain Ni-MoS2 HDS catalysts with different structures. Mechanisms of hydrothermal treatment and calcination on Ni-MoS2 catalyst structures were investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), electron paramagnetic resonance (EPR), and X-ray photoelectron spectroscopy (XPS). The catalytic performance of Ni-MoS2 catalysts was evaluated by the HDS reaction of dibenzothiophene (DBT) on a fixed bed reactor, and the structure-activity relationship between the structures of the Ni-MoS2 catalyst and the HDS of DBT was discussed. The results showed that the lateral size, the number of stacked layers, and the S/Mo atomic ratio of MoS2 in the catalyst decreased and then increased with the increase of the hydrothermal treatment temperature, reaching the minimum at the hydrothermal treatment temperature of 150 °C, i.e., the lateral size of MoS2 in the catalyst was 20-36 nm, the number of stacked layers of MoS2 was 5.4, and the S/Mo ratio in the catalyst was 1.80. In addition, the effects of different calcination temperatures and calcination atmospheres on the catalyst structures were investigated at the optimum hydrothermal treatment temperature. The Ni-Mo-S and NixSy ratios of the catalysts increased and then decreased with the increasing calcination temperature under a H2 atmosphere, reaching a maximum at a calcination temperature of 400 °C. Therefore, DBT exhibited the best HDS activity over the H-NiMo-150-400 catalyst, and the desulfurization rate of DBT reached 94.7% at a reaction temperature of 320 °C.

Carbon nitride used as a reactive template to prepare mesoporous molybdenum sulfide and nitride

Carbon nitride C3N4 has been used as a sacrificial template to prepare inorganic materials with hierarchical pore structure. C3N4 impregnated with ammonium heptamolybdate was treated in reactive gas mixtures (H2S/H2 or NH3/H2). This approach allowed mesoporous molybdenum sulfide and molybdenum nitride materials to be obtained that replicate the morphology of the C3N4 template. Advantageous catalytic properties have been demonstrated in the thiophene hydrodesulfurization (HDS) and electrochemical hydrogen evolution reaction (HER). The highest rates in both reactions were observed for partially sulfidized Mo2N solid.

Influence of Pluronic® P123 Addition in the Synthesis of Bulk Ni Promoted MoS2 Catalyst. Application to the Selective Hydrodesulfurization of Sulfur Model Molecules Representative of FCC Gasoline

A way to improve hydrotreatment processes is to enhance the intrinsic activity of Ni or Co promoted MoS2 catalysts that are commonly used in such reactions. The aim of this work was to investigate the impact of the presence of Pluronic® P123 as a structuring agent during the synthesis of Ni promoted MoS2 catalysts (named NiMoS) in water at room temperature. A series of analyses, i.e., X-ray diffraction (XRD), chemical analysis, inductively coupled plasma mass spectrometry (ICP-MS), nitrogen adsorption-desorption isotherms, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS), helped in characterizing the NiMoS-P123 and NiMoS catalysts, the latter being prepared in the absence of polymer. Both compounds contained MoS2 phase (~85 atomic% considering Mo atoms), a similar amount of mixed Ni-Mo-S phase (40–50% considering Ni) and some amount of NiS and Ni-oxidized impurity phases. The main differences between the two catalysts were a much larger specific surface area (126 m2·g−1 instead of 31 m²·g−1) and a better dispersion of the active phase as shown by the lower slab stacking (2.7 instead of 4.8) for NiMoS-P123, and the presence of C in NiMoS-P123 (9.4 wt.% instead of 0.6 wt.%), indicating an incomplete decomposition of the polymer during thermal treatment. Thanks to its larger specific surface area and lower slab stacking and therefore modification of active Mo site properties, the compound prepared in the presence of Pluronic® P123 exhibits a strong increase of the catalytic activity expressed per Mo atom for the transformation of 3-methylthiophene. Such improvement in catalytic activity was not observed for the transformation of benzothiophene likely due to poisonous residual carbon which results from the presence of Pluronic® P123 during the synthesis.

In situ growth of CuS decorated graphene oxide-multiwalled carbon nanotubes for ultrasensitive H2O2 detection in alkaline solution

A novel hybrid nanomaterial composed of nanoparticles, nanotubes and nanosheets for electrochemical H₂O₂ detection.

Movement of new direction from conjugated polymer to semiconductor composite polymer nanofiber

In the past few years, there was a tremendous growth in conjugated polymer nanofibers via design of novel conjugated polymers with inorganic materials. Synthetic routes to these conjugated polymers involve new, mild polymerization techniques, which enable the formation of well-defined polymer architectures. This review provides interest in the development of novel (semi) conducting polymers, which combine both organic and inorganic blocks in one framework. Due to their ability to act as chemosensors or to detect various chemical species in environmental and biological systems, fluorescent conjugated polymers have gained great interest. Nanofibers of metal oxides and sulfides are particularly interesting in both their way of applications and fundamental research. These conjugated nanofibers operated for many applications in organic electronics, optoelectronics, and sensors. Synthesis of electrospun fibers by electrospinning technique discussed in this review is a simple method that forms conjugated polymer nanofibers. This review provides the basics of the technique and its recent advances in the formation of highly conducting and high-mobility polymer fibers towards their adoption in electronic application.

Recent developments in 2D layered inorganic nanomaterials for sensing

Two dimensional layered inorganic nanomaterials (2D-LINs) have recently attracted huge interest because of their unique thickness dependent physical and chemical properties and potential technological applications. The properties of these layered materials can be tuned via both physical and chemical processes. Some 2D layered inorganic nanomaterials like MoS2, WS2 and SnS2 have been recently developed and employed in various applications, including new sensors because of their layer-dependent electrical properties. This article presents a comprehensive overview of recent developments in the application of 2D layered inorganic nanomaterials as sensors. Some of the salient features of 2D materials for different sensing applications are discussed, including gas sensing, electrochemical sensing, SERS and biosensing, SERS sensing and photodetection. The working principles of the sensors are also discussed together with examples.

Structural instability and mechanical properties of MoS2toroidal nanostructures

Classic molecular dynamics (MD) simulation of hypothetical MoS₂NT nanorings and their woven hierarchical structures shows a strong dimension-dependent structural stability, and reveals that the hierarchical structures with 4-in-1 weaves exhibit high tensile strength and Young's modulus.