Journal articles: 'MoS2 Nanoparticles'

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Chikukwa, Evernice, Edson Meyer, Johannes Mbese, and Nyengerai Zingwe. "Colloidal Synthesis and Characterization of Molybdenum Chalcogenide Quantum Dots Using a Two-Source Precursor Pathway for Photovoltaic Applications." Molecules 26, no. 14 (July 9, 2021): 4191. http://dx.doi.org/10.3390/molecules26144191.

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The drawbacks of utilizing nonrenewable energy have quickened innovative work on practical sustainable power sources (photovoltaics) because of their provision of a better-preserved decent environment which is free from natural contamination and commotion. Herein, the synthesis, characterization, and application of Mo chalcogenide nanoparticles (NP) as alternative sources in the absorber layer of QDSSCs is discussed. The successful synthesis of the NP was confirmed as the results from the diffractive peaks obtained from XRD which were positive and agreed in comparison with the standard. The diffractive peaks were shown in the planes (100), (002), (100), and (105) for the MoS2 nanoparticles; (002), (100), (103), and (110) for the MoSe2 nanoparticles; and (0002), (0004), (103), as well as (0006) for the MoTe2 nanoparticles. MoSe2 presented the smallest size of the nanoparticles, followed by MoTe2 and, lastly, by MoS2. These results agreed with the results obtained using SEM analysis. For the optical properties of the nanoparticles, UV–Vis and PL were used. The shift of the peaks from the red shift (600 nm) to the blue shift (270–275 nm and 287–289 nm (UV–Vis)) confirmed that the nanoparticles were quantum-confined. The application of the MoX2 NPs in QDSSCs was performed, with MoSe2 presenting the greatest PCE of 7.86%, followed by MoTe2 (6.93%) and, lastly, by MoS2, with the PCE of 6.05%.

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Mandal, Soumen, Rajulapati Vinod Kumar, and Nagahanumaiah. "Silver and molybdenum disulfide nanoparticles synthesized in situ in dimethylformamide as dielectric for micro-electro discharge machining." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 233, no. 5 (September 30, 2017): 1594–99. http://dx.doi.org/10.1177/0954405417733019.

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The research focuses on the applicability of silver (Ag) and molybdenum disulfide (MOS2) nanoparticle synthesized in situ in dimethylformamide solution as dielectric material for micro-electro discharge machining. Ag nanoparticles (~120 nm size) and MOS2 nanoparticles (~20 nm size) were synthesized in dimethylformamide solution using a combination of nanoparticle solution synthesis routes. A setup for micro-electro discharge machining was developed in-house with an arrangement to generate spark at varying voltages. The setup was integrated with a precise linear height gauge to measure the spark gap during the experiments where Ag and MOS2 nanoparticles in dimethylformamide solution served as dielectric. The debris was collected and was characterized for each of the experiments. The feature size of the crater generated during the micro-electro discharge machining was also studied. The experiments were repeated with silver and MOS2 nanoparticle powder mixed with dimethylformamide as dielectric. It was observed that in situ prepared nanoparticles in dimethylformamide offered much better machining performance in terms of process stability, crater size and material removal rates. On use of in situ synthesized nanoparticle dielectric, the material removal rate increased by nearly two to three times whereas the spark gap increased by about two times.

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Hu, J. J., J. H. Sanders, and J. S. Zabinski. "Synthesis and microstructural characterization of inorganic fullerene-like MoS2 and graphite-MoS2 hybrid nanoparticles." Journal of Materials Research 21, no. 4 (April 1, 2006): 1033–40. http://dx.doi.org/10.1557/jmr.2006.0118.

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The structures of inorganic fullerene-like (IF) MoS2 nanoparticles produced by arc discharge in water are reported in this paper. To adjust the chemistry and structure of IF nanoparticles, 2H–MoS2, graphite and composite 2H–MoS2/graphite rods were used as electrodes in the arc synthesis. In comparison to using MoS2 as both anode and cathode, mixed electrodes (graphite and MoS2) significantly increased the discharge current. Various IF-MoS2 nanoparticles were successfully produced by the water-based arc method, and their microstructures were studied using a transmission electron microscope equipped with an x-ray energy dispersive spectrometer. The IF–MoS2 nanoparticles commonly had a solid core wrapped with a few MoS2 layers and exhibit some differences in size and geometry. The IF-MoS2 nanoparticles were typically 5–30 nm in diameter as observed by transmission electron microscopy. Tiny IF-MoS2 nanoparticles (<10 nm) along with fragments of lamellar MoS2 were produced from arc discharge in water using both graphite and MoS2 electrodes. Carbon nano-onions and hybrid nanoparticles consisting of carbon and MoS2 were synthesized by using mixed electrodes of graphite and 2H–MoS2. The hybrid nanoparticles were MoS2 cores covered by a graphite shell. Our results show that the water-based arc method provides a simple tool for producing a variety of nanoparticles including some familiar and some new hybrid structures.

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Liu, Xianglin, Yongsong Ma, Peng Li, Huayi Yin, and Dihua Wang. "Preparation of MoB₂ Nanoparticles by Electrolysis of MoS₂/B Mixture in Molten NaCl-KCl at 700 °C." Journal of The Electrochemical Society 168, no. 12 (December 1, 2021): 123509. http://dx.doi.org/10.1149/1945-7111/ac41f4.

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MoB2 is synthesized by the electrochemical reduction of solid MoS2/B mixture in molten NaCl-KCl at 700 °C. Unlike the traditional methods, the electrolysis method employs the low-cost MoS2 feedstock and the boronization reaction happens at a low temperature of 700 °C. The electrochemically induced boronization involves two steps: the electrochemical desulfurization to generate Mo and the reaction of Mo with B to form MoB2. The S2− released from the reduction of MoS2 transfers to the carbon anode and is oxidized to sulfur gas, realizing a green synthetic process. In addition, the influences of molar ratio of MoS2 and amorphous boron and electrolysis cell voltage on the phase composition and morphology of electrolytic products were studied. The obtained MoB2 particles possess a uniform nodular morphology. Overall, this paper provides a straightforward and green process to prepare MoB2 nanoparticles using economically affordable raw materials at low temperature, and this method can be extended to prepare other borides.

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Hu, Kun Hong, Xian Guo Hu, Xiao Jun Sun, He Feng Jing, and Song Zhan. "Synthesis and Characterization of Nanosize Molybdenum Disulfide Particles by Quick Homogeneous Precipitation Method." Key Engineering Materials 353-358 (September 2007): 2107–10. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.2107.

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Molybdenum sulfide nanoparticles were prepared via quick homogeneous precipitation method (QHPM) by the reaction between Na2MoO4 and CH3CSNH2 in the presence of sulfuric acid at 80 oC. The as-synthesized molybdenum sulfide particles were studied by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The results showed that the as-synthesized molybdenum sulfide was amorphous MoS3 nanoparticles with an average size of 40 nm. The resultant amorphous MoS3 nanoparticles were then calcined under hydrogen gas flow at a selected temperature for 50 minutes. The results of XRD, TEM, and HRTEM confirmed that the MoS2 nanoparticles with about 40 nm were prepared from the amorphous MoS3 nanoparticles at 780 oC.

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Ilie, Filip, and Andreea-Catalina Cristescu. "A Study on the Tribological Behavior of Molybdenum Disulfide Particles as Additives." Coatings 12, no. 9 (August 25, 2022): 1244. http://dx.doi.org/10.3390/coatings12091244.

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Molybdenum disulfide (MoS2) is used as a solid lubricant and is well known for its tribological behavior (friction and wear). The tribological properties of the lubricating oil–MoS2 nanoparticles mixture in different conditions of friction are studied using a four-ball tribometer, and the operating conditions of the four balls when immersed can be modeled. The current paper presents a calculating method for the critical sliding velocity (ωcr) and friction maximum torque (Mfmax) depending on the temperature (T) from the contact areas, obviously demonstrating low tribological performances. The film composition formed by friction, the topography, and the morphology of the particles and the friction-and-wear tracks of the balls following experiments using contact surfaces are analyzed and investigated by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscope (TEM). XPS and SEM show that nanoparticles by deposition form a protective and lubricating layer of MoS3, which allows for an increase in the friction pair’s load capacity. MoS2 nanoparticles (n- MoS2 of ~ 40 nm in diameter) compared to the common (commercial) MoS2 particles (c-MoS2 of ~ 1.5 μm in diameter) presented lower friction coefficients and higher wear-resistance values, due to the protective-layer microstructure as an intermediate lubricant between the contact surfaces. Therefore, the present paper reports the tribological properties of the lubricating oil with n-MoS2 as an additive compared to the c-MoS2, and by the application of the friction modeling theory using a Couette flow, it was possible to calculate the temperature, T, when the friction torque, Mf, was at its maximum, the basis on which the value of its sliding velocity, ω, was obtained corresponding to the contact areas of the four-ball system.

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Gao, Bin, and Xiao Jun Zhang. "Synthesis of MoS₂ Nanoparticles with Inorganic Fullerene-Like Structure from Molybdenum Trioxide and Sulfur." Advanced Materials Research 554-556 (July 2012): 601–4. http://dx.doi.org/10.4028/www.scientific.net/amr.554-556.601.

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MoS2 nanoparticles with fullerene-like (IF-MoS2) structure were successfully obtained at heating temperature higher than 840 °C by chemical vapor deposition method in a three-tube furnace using MoO3 and S (sulfur) powders as raw materials. The synthesized samples were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and energy dispersion X-ray spectrometerrespectively. IF-MoS2 nanoparticles can be obtained only in the narrow temperature range of 840 °C-870 °C, and the diameter of IF-MoS2 nanoparticles increases with temperature. A gradual formation mechanism of IF-MoS2 nanoparticles was discussed in detail.

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Shi, Shih-Chen, and Shia-Seng Pek. "Third-Body and Dissipation Energy in Green Tribology Film." Applied Sciences 9, no. 18 (September 10, 2019): 3787. http://dx.doi.org/10.3390/app9183787.

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Green tribology film comprising hydroxypropyl methylcellulose modified with nanoparticles and molybdenum disulfide was prepared by the solvent evaporation method. The nanoparticle additives were Al, Cu, Al2O3, and CuO. The tribological behavior of nanoparticles and MoS2 was investigated using a ball-on-disk tribometer. The surface morphologies and worn surfaces were observed through scanning electron microscopy. The preferred orientation and crystallographic structure of MoS2 and nanoparticles in the composites were studied via X-ray diffraction. Energy-dispersive X-ray spectroscopy was used to analyze the transfer film formed on the counterball. The surface profile, wear depth, wear width, and wear volume were studied by a 3D optical profiler. The synergistic effect of micro-platelet MoS2 and nanoparticles contributed to the excellent wear resistances. It was found that the wear volume of hydroxypropyl methylcellulose (HPMC)/MoS2 composites decreased dramatically when Al, Cu, and CuO were used as fillers, and it decreased slightly with Al2O3. The optimal wear resistance was obtained with 3 wt.% additives. These filled composites had a lower coefficient of friction lower than that of unfilled HPMC/MoS2. The optimal result was observed for the HPMC/MoS2/CuO 3 wt.% composite coating, which reduces the wear and friction coefficient by 90% and 84%, respectively, as compared to coatings without additives. Nanoparticles existed in the wear track as the third particles improved the load capacity of the composites. The wear mechanism of the composites is discussed in terms of the worn surfaces and the analysis of transfer film with a third-body approach. The dissipation energy theory is used to evaluate the dominant wear mechanism of the system.

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Guo, Jianjun, Bo Yang, Qiang Ma, Sandra Senyo Fometu, and Guohua Wu. "Photothermal Regenerated Fibers with Enhanced Toughness: Silk Fibroin/MoS2 Nanoparticles." Polymers 13, no. 22 (November 15, 2021): 3937. http://dx.doi.org/10.3390/polym13223937.

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The distinctive mechanical and photothermal properties of Molybdenum sulfide (MoS2) have the potential for improving the functionality and utilization of silk products in various sectors. This paper reports on the preparation of regenerated silk fibroin/molybdenum disulfide (RSF/MoS2) nanoparticles hybrid fiber with different MoS2 nanoparticles contents by wet spinning. The simulated sunlight test indicated that the temperature of 2 wt% RSF/MoS2 nanoparticles hybrid fibers could rise from 20.0 °C to 81.0 °C in 1 min and 98.6 °C in 10 min, exhibiting good thermal stability. It was also demonstrated that fabrics made by manual blending portrayed excellent photothermal properties. The addition of MoS2 nanoparticles could improve the toughness of hybrid fibers, which may be since the mixing of MoS2 nanoparticles hindered the self-assembly of β-sheets in RSF solution in a concentration-dependent manner because RSF/MoS2 nanoparticles hybrid fibers showed a lower β-sheet content, crystallinity, and smaller crystallite size. This study describes a new way of producing high toughness and photothermal properties fibers for multifunctional fibers’ applications.

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Lee, G. H., J. W. Jeong, S. H. Huh, S. H. Kim, B. J. Choi, and Y. W. Kim. "A Simple Synthetic Route to MoS2 and WS2 Nanoparticles and Thin Films." International Journal of Modern Physics B 17, no. 08n09 (April 10, 2003): 1134–40. http://dx.doi.org/10.1142/s0217979203018636.

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We produced both MoS2 and WS2 nanoparticles by thermally decomposing M(CO)6 (M = Mo, W) in excess of H2S by using a hot filament. Both highly pure crystalline MoS2 and WS2 nanoparticles were efficiently produced over the filament temperature range from 300 to 800 °C. Particle diameter ranged from 2.0 to 5.0 nm and from 3.0 to 6.0 nm for MoS2 and WS2 nanoparticles, respectively. Fullerene-like particles such as nanotubes, onions, and empty and nested hollows were not produced. Both MoS2 and WS2 nanoparticles have a hexagonal close packed structure. Cell constants are determined to be a = 3.09 and c = 12.61 Å and a = 3.09 and c = 12.47 Å for MoS2 and WS2 nanoparticles, respectively, which are all consistent with the corresponding bulk values. Thin films of MoS2 and WS2 were also prepared by chemical vapor deposition of MoS2 and WS2 on stainless steel disks at 600-650 °C and low friction coefficients were obtained at an ambient atmosphere for both MoS2 and WS2 thin films, implying that they can serve as good solid lubricants.

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Hao, Xiaoguang, and Weijing Li. "Molybdenum Dioxide (MoS2)/Gadolinium (Gd) Containing Arginine-Glycine-Aspartic Acid (RGD) Sequences as New Nano-Contrast Agent for Cancer Magnetic Resonance Imaging (MRI)." Journal of Nanoscience and Nanotechnology 21, no. 3 (March 1, 2021): 1403–12. http://dx.doi.org/10.1166/jnn.2021.18894.

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Molybdenum dioxide-gadolinium-arginine/glycine/aspartic acid (MoS2-Gd-RGD) sequences targeting nano-contrast agents that specifically bind to human hepatocellular carcinoma (HCC) HepG2 cells were synthesized, and their targeting imaging effects on HCC cells and models were evaluated. Zeta potential, particle size and Fourier Transform Infrared Spectrometer (FTIR) were used to characterize the nano-contrast agent, and its cytotoxicity was evaluated. The MoS2-Gd nanoparticles were used as control in vitro to determine the targeting capability of the MoS2-Gd-RGD nanoparticles toward integrin αvβ3. During in vivo animal experiments, 12 nude mice with tumors were randomly divided into three groups to compare the imaging effects of the MoS2-Gd-RGD and MoS2-Gd groups. The hydrodynamic diameter of MoS2-Gd-RGD nanoparticles was approximately 336.43±6.43 nm, and the polydispersity index (PDI) value reached 0.132. Transmission electron microscopy showed the uniform particle size and good dispersion of the nanoparticles. The relaxation rate totaled 1.39 mM−1S−1. The signal value of the T1-weighted image of the HepG2 cells treated with MoS2-Gd-RGD was higher than that of the non-targeted materials (MoS2-Gd) (P < 0.01). The signal value of the tumor increased significantly 15 min after the tail vein injection with MoS2-Gd-RGD, and it peaked at 60 min after injection. A significant difference in tumor signal values was observed between the two groups of nude mice injected with MoS2-Gd-RGD and MoS2- Gd (P < 0.01). At the in vitro and in vivo experiments, the MoS2-Gd-RGD nanoparticles presented the characteristics of integrin αvβ3 targeting. Thus, MoS2-Gd-RGD nanoparticles feature potential as contrast agents for MRI.

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Li, Jingze, Jiaxin Ma, Liu Hong, and Cheng Yang. "Prominent antibacterial effect of sub 5 nm Cu nanoparticles/MoS₂ composite under visible light." Nanotechnology 33, no. 7 (November 25, 2021): 075706. http://dx.doi.org/10.1088/1361-6528/ac3577.

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Abstract Achieving an efficient and inexpensive bactericidal effect is a key point for the design of antibacterial agent. Recent advances have proved molybdenum disulfide (MoS2) as a promising platform for antimicrobial applications, while the combination of metal nanoparticle would promote the antibacterial efficiency. Nevertheless, the dispersivity, cheapness and safety of metal nanoparticle loaded on MoS2 raised some concerns. In this paper, we successfully realized a uniform decoration of copper nanoparticles (CuNPs) on surface of MoS2 nanosheets, and the size of CuNPs could be controlled below 5 nm. Under 5 min irradiation of 660 nm visible light, the synthesized CuNPs/MoS2 composite demonstrated superior antibacterial performances (almost 100% bacterial killed) towards both Gram-negative E. coli and Gram-positive S. aureus over the single component (Cu or MoS2), while the bactericidal effect could last for at least 6 h. The synergism of photodynamic generated hydroxyl radical (·OH), oxidative stress without reactive oxygen species production and the release of Cu ions was considered as the mechanism for the antibacterial properties of CuNPs/MoS2. Our findings provided new insights into the development of two-dimensional antibacterial nanomaterials of high cost performance.

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Cheng, Xiaorong, Yuhua Lu, Shoulin Gu, and Graham Dawson. "MoS2/Au-Sensitized TiO2 Nanotube Arrays with Core–Shell Nanostructure for Hydrogen Production." Nano 12, no. 09 (September 2017): 1750115. http://dx.doi.org/10.1142/s1793292017501156.

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Herein, a TiO2 NTAs-Au-MoS2 core–shell photoanode was constructed with the intention to fulfill the efficient transfer of photo-generated carriers to the photoelectrode’s surface. Au nanoparticles were decorated by a drop casting method, and the MoS2 layer was deposited above the Au nanoparticles using a photoreduction-annealing process. Au nanoparticles were well dispersed on the inner wall of the TiO2 nanotubes and covered by the MoS2 layer, forming a core–shell nanostructure. The MoS2 layer significantly improved the attachment between Au nanoparticles and TiO2 NTAs, resulting in increased PEC stability and performance. Attributed to the excitation of Au nanoparticles’ localized surface plasmon resonance effect and visible light utilization of MoS2, the TiO2 NTAs-Au-MoS2 core–shell photoanode exhibits greatly enhanced photocurrent density. An increase from 67[Formula: see text][Formula: see text]A/cm2 to 234[Formula: see text][Formula: see text]A/cm2 under Xe lamp illumination and from 2.6[Formula: see text][Formula: see text]A/cm2 to 12.6[Formula: see text][Formula: see text]A/cm2 under visible light illumination ([Formula: see text][Formula: see text]nm) compared with the TiO2 NTAs was observed.

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Samantra, Sonali, and Sirsendu Sekhar Ray. "Heterogeneous Mixture of Nanoparticles from MoS2 and Ta2O5: Synthesis and Characterization." Volume 4,Issue 5,2018 4, no. 5 (August 31, 2018): 492–96. http://dx.doi.org/10.30799/jnst.153.18040508.

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The synthesis of metallic nanoparticles is an active area of academic and application research in nanotechnology. It is also an amalgamating technology which has fascinating multi-disciplinary application in various sections. Nanoparticles has been a conventional but field if we go on further decreasing the size we enter the field of quantum dots (<10 nm) with application in the form of tracers, labels, sensors etc. Molybdenum disulfide and tantalum nanoparticles were synthesized and characterized through FESEM, FTIR, XRD,UV-Vis spectroscopy, spectrofluorimetry, etc. The size of the synthesized nanoparticles as observed in FESEM were found to be in the range of 22 to 50 nm for molybdenum nanoparticle and 34.72 to 72.45 nm in case of tantalum. The EDAX analysis shows the composition of molybdenum nanoparticle as hydrogen(H), molybdenum(Mo), nitrogen(N), oxygen(O) and fluorine(F) with 32.3%, 66.3%, 0.43%, 0.32% and 0.5% respectively. The EDAX analysis show the composition of tantalum nanoparticle as hydrogen(H), tantalum(Ta), oxygen(O), nitrogen(N) and fluorine(F) with 35.9%,50%,4.8%,2.01%,7.17%. The XRD analysis of molybdenum disulfide images indicates the synthesized nanoparticle as crystalline in nature. The average crystallinity was found to be 7.93 nm. Tantalum nanoparticles with a crystallinity of 8.05 and 12.20 nm were observed as [2 0 0] and [1 1 0] planes. Biocompatibility of the synthesized nanoparticles was examined by MTT assay. The spectrofluorometry of the synthesized nanoparticles proves the fluorescence property which is most probably because of the quantum dots. Furthermore, the fluorescence property was also used for the cell imaging. The study is a first its kind to exercise the use of Mo and Ta quantum dots in the field of biomedical application and further work is necessary for optimization and implementation of the nanoparticles in the biological sector.

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Nazir, Asif, Muhammad Suleman Tahir, Ghulam Mustafa Kamal, Xu Zhang, Muhammad Bilal Tahir, Bin Jiang, and Muhammad Safdar. "Fabrication of Ternary MoS2/CdS/Bi2S3-Based Nano Composites for Photocatalytic Dye Degradation." Molecules 28, no. 7 (April 2, 2023): 3167. http://dx.doi.org/10.3390/molecules28073167.

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The synthesis and design of low-cost visible-light-active catalysts for the photodegradation of organic dyes have been regarded as an efficient way to use solar energy in addressing environmental issues. We report the fabrication of MoS2/CdS nanoparticles functionalized with Bi2S3 nanoflakes. The ternary composites of “MoS2/CdS/Bi2S3” were synthesized in situ by a hydrothermal method at different temperatures. The changes in structural, optical, and morphological properties of the synthesized CdS/MoS2/Bi2S3 were explored. The effects of Bi2S3 on CdS/MoS2 were thoroughly studied by performing an X-ray diffractometer (XRD), a scanning electron microscope (SEM), an ultra-violet–visible spectrometer (Uv–vis), and Fourier transform infrared spectroscopic (FT-IR) studies of the nanoparticles. XRD confirms the cubical crystal structure of the nanoparticles. SEM studies possess the modulation in the surface morphology with the tenability in volume ratios of “MoS2/CdS/Bi2S3” composites. It was observed that the bandgaps calculated using absorption measurements could be manipulated from 2.40 eV to 0.97 eV with varying Bi2S3 in the MoS2/CdS nanostructures. FT-IR confirmed the synthesis of “MoS2/CdS/Bi2S3” nanoparticles. On allowing the visible light to fall for 120 min, it was observed that “MoS2/CdS/Bi2S3” degrades the methylene blue up to 90%. The calculated results of “MoS2/CdS/Bi2S3” suggest that the synthesized material could be a strong candidate for photodegradation applications. This research work explains the synthesis of MoS2/CdS/Bi2S3-based nanocomposites for the degradation of dye using a photocatalytic process. The final results show that this catalyst effectively degrades the dye.

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Yan, Haochen, Fuqiang Liu, Jinna Zhang, and Yanbiao Liu. "Facile Synthesis and Environmental Applications of Noble Metal-Based Catalytic Membrane Reactors." Catalysts 12, no. 8 (August 5, 2022): 861. http://dx.doi.org/10.3390/catal12080861.

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Noble metal nanoparticle-loaded catalytic membrane reactors (CMRs) have emerged as a promising method for water decontamination. In this study, we proposed a convenient and green strategy to prepare gold nanoparticle (Au NPs)-loaded CMRs. First, the redox-active substrate membrane (CNT-MoS2) composed of carbon nanotube (CNT) and molybdenum disulfide (MoS2) was prepared by an impregnation method. Water-diluted Au(III) precursor (HAuCl4) was then spontaneously adsorbed on the CNT-MoS2 membrane only through filtration and reduced into Au(0) nanoparticles in situ, which involved a “adsorption–reduction” process between Au(III) and MoS2. The constructed CNT-MoS2@Au membrane demonstrated excellent catalytic activity and stability, where a complete 4-nitrophenol transformation can be obtained within a hydraulic residence time of <3.0 s. In addition, thanks to the electroactivity of CNT networks, the as-designed CMR could also be applied to the electrocatalytic reduction of bromate (>90%) at an applied voltage of −1 V. More importantly, by changing the precursors, one could further obtain the other noble metal-based CMR (e.g., CNT-MoS2@Pd) with superior (electro)catalytic activity. This study provided new insights for the rational design of high-performance CMRs toward various environmental applications.

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Стовпяга, Е. Ю., Д. А. Курдюков, Д. А. Кириленко, А. Н. Смирнов, А. В. Швидченко, М. А. Яговкина, and В. Г. Голубев. "Темплатный метод синтеза монодисперсных наночастиц MoS-=SUB=-2-=/SUB=-." Физика и техника полупроводников 55, no. 5 (2021): 475. http://dx.doi.org/10.21883/ftp.2021.05.50841.9587.

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Monodisperse molybdenum disulfide nanoparticles were synthesized in mesopores of spherical silica particles (mSiO2) served as a template. First, the pores of mSiO2 particles were impregnated with the precursor (ammonium tetrathiomolybdate solution). Then, the reduction of the filler in thermodynamically equilibrium conditions in H2S/H2 atmosphere was carried out. The template material (a-SiO2) was selectively etched from the composite mSiO2/MoS2 particles with HF to obtain individual MoS2 nanoparticles. The mean size of MoS2 nanoparticles determined by microscopic methods was found to be 3.5 nm. According to dynamic light scattering data, the nanoparticles had low size scatter (18%).

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Jazaa, Yosef, Tian Lan, Sonal Padalkar, and Sriram Sundararajan. "The Effect of Agglomeration Reduction on the Tribological Behavior of WS2 and MoS2 Nanoparticle Additives in the Boundary Lubrication Regime." Lubricants 6, no. 4 (December 10, 2018): 106. http://dx.doi.org/10.3390/lubricants6040106.

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This study investigates the impact of different surfactants and dispersion techniques on the friction and wear behavior of WS2 and MoS2 nanoparticles additives in a Polyalphaolefin (PAO) base oil under boundary lubrication conditions. The nanoparticles were dispersed using Oleic acid (OA) and Polyvinylpyrrolidone (PVP) to investigate their impact on particle agglomeration. The size distribution of the dispersed nanoparticles in PAO was measured by dynamic light scattering. The nanoparticles treated using PVP resulted in the most stable particle size. Friction studies showed that nanoparticle agglomeration reduction and the homogeneity of the suspension did not significantly impact the friction reduction behavior of the lubricant. Reciprocating wear experiments showed that, for our test conditions, both WS2 and MoS2 nano additives exhibited maximum wear depth reduction (45%) when using the PVP surface treatment compared to base oil. The wear results confirmed the significance of minimizing agglomeration and promoting high dispersion in promoting favorable wear resistance under boundary lubricant conditions. Analysis of the wear surfaces showed that a tribofilm formation was the primary wear reduction mechanism for WS2 particles treated by PVP while, in the case of MoS2 treated by PVP, the mechanism was load sharing via particles rolling and/or sliding at the interface.

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Dong, Pham Quang, Tran Minh Duc, Ngo Minh Tuan, Tran The Long, Dang Van Thanh, and Nguyen Van Truong. "Improvement in the Hard Milling of AISI D2 Steel under the MQCL Condition Using Emulsion-Dispersed MoS2 Nanosheets." Lubricants 8, no. 6 (June 5, 2020): 62. http://dx.doi.org/10.3390/lubricants8060062.

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The present work shows the process for MoS2 nanosheet production by liquid N2-queched bulk, a novel method having highly efficient, green, and facile operation. The produced MoS2 nanoparticles are suspended in minimum quantity cooling lubrication (MQCL)-based fluid to form nanofluid used for the hard milling of AISI D2 steel. The study aims to improve the hard-milling performance assisted by the MQCL technique using MoS2 nanofluid. ANOVA analysis is used to evaluate the effects of three input machining variables, including nanoparticle concentration, cutting speed, and material hardness on cutting forces. The results indicate that the better cooling effect from the principle of the Ranque–Hilsch vortex tube of the MQCL device combined with the better lubricating performance from MoS2 nanofluid brings out the sustainable alternative solution for machining difficult-to-cut material. Moreover, the experimental results provide the technical guides for the selection of proper values of nanoparticle concentration and cutting speed while ensuring the technological, economic, and environmental characteristics.

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Gugulothu, Srinu, and Vamsi Krishna Pasam. "Performance Evaluation of CNT/MoS2 Hybrid Nanofluid in Machining for Surface Roughness." International Journal of Automotive and Mechanical Engineering 16, no. 4 (December 30, 2019): 7413–29. http://dx.doi.org/10.15282/ijame.16.4.2019.15.0549.

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Present work is motivated by the high thermal conductivity of MWCNT and low coefficient of friction due to MoS2 nanoparticles which can significantly improve the heat transfer and lubrication performance of hybrid nanofluids than nanofluids. Hybrid nanofluids are prepared with CNT/MoS2 nanoparticles of 1wt% in sesame oil, neem oil and mahua oil by varying hybrid ratio (i.e. 1: 1; 1:2 and 2:1) and surfactant. The hybrid nanofluid composition is evaluated based on stability analysis from sedimentation and zeta potential studies. The concentration of nanoparticles is varied by preparing CNT/MoS2 hybrid nanofluid using obtained composition for stability and selected the optimal concentration for the lowest coefficient of friction obtained in friction test. The property of thermal conductivity is also evaluated for varying concentration of hybrid nanofluid at room temperature. The contact angle for CNT/MoS2 hybrid nanofluids is evaluated with a contact angle meter to understand the lubrication effect. Experimental findings for stable hybrid nanofluid are found to be sesame oil, SDS with 15% content of nanoparticle weight and 1:2 hybrid ratio. From friction test, it is observed that 2 wt%concentration is optimal for least coefficient of friction (0.038). Minimum surface roughness (Ra) is observed with 2 wt% of hybrid nanofluid compared to dry machining and conventional cutting fluid. Optimum conditions for minimum surface roughness are evaluated in turning of AISI1040 steel with the use of 2wt% of CNT/MoS2 hybrid nanofluid in RSM. Ra value is observed to decrease with an increase in cutting speed and increased with an increase in feed and depth of cut.

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Fraih, Ali Jabbar, and Zainab Ali Hrbe. "Enhanced photocatalytic performance of molybdenum disulfide-copper oxide nanoparticles photoanodes." European Physical Journal Applied Physics 96, no. 3 (December 2021): 30102. http://dx.doi.org/10.1051/epjap/2021210192.

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In this paper, the molybdenum disulfide (MoS2)/copper oxide (CuO) heterostructure is introduced in a very simple way for photoelectrochemical application. MoS2 multilayers were prepared by sonication method and decorated with copper oxide nanoparticles through its thin film deposition layer and heating in argon atmosphere. SEM, TEM, AFM, absorption and Raman analyses were employed to characterize the nanostructures. The results show that the presence of copper oxide nanoparticles reduces the recombination rate of photogenerated electron-holes in MoS2 multilayers and produces a significant photocurrent compared to the individual MoS2 electrode. Such a proposed structure demonstrates a high potential for photoelectrochemical applications.

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Chai, Hongyan, Xueyong Wang, Zhimin Liu, and Yuehan Zhao. "Study on the removal of amyloid plaque by nano-gold in the treatment of neurodegenerative disease-alzheimer’s disease." Materials Express 11, no. 7 (July 1, 2021): 1038–44. http://dx.doi.org/10.1166/mex.2021.1992.

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As a complex neurological disease, the treatment of Alzheimer’s disease (AD) is a global challenge. Compared with traditional drug therapy, a novel therapeutic tool, inorganic nanoparticles combined with photothermal therapy (PTT) can decompose amyloid β-protein (Aβ) fibrils and inhibit Aβ aggregation, alleviating AD symptoms. In this study, MoS2@Au NPs composite nanoparticles were constructed by combining sulfhydryl-modified Au NPs and MoS2 nanosheets. In vitro experiments showed that the composite nanoparticles could degrade insoluble Aβ fibers to soluble monomers and alleviate neurotoxicity. Additionally, the excellent biocompatibility and biosafety of MoS2@Au NPs reduced the damaging effects on nerve cells, and the AD model mice benefited from the treatment with MoS2@Au NPs, which significantly improved their learning and cognitive abilities and thus reduced the disease. More importantly, MoS2@Au NPs combined with PTT effectively curbed the inflammatory response and slowed down the course of AD.

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Mkhalid, I. A. "Degradation of Foron Dye by Means of Orderly Dispersion of MoS2 Nanoparticles on Mesoporous ZnO Systems Using Visible Light." Nanoscience and Nanotechnology Letters 11, no. 11 (November 1, 2019): 1531–39. http://dx.doi.org/10.1166/nnl.2019.3040.

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For the first time, we in this study prepared uniform MoS2 nanoparticles on ZnO mesoporous. XRD patterns established that the synthesized ZnO and MoS2/ZnO samples were composed of ZnO phase. The TEM results revealed that MoS2 and ZnO were very close to each other, with 4–8 nm in sizes of particles. The MoS2/ZnO nanocomposites have many advantages, and some of these advantages are large surface area (105 m2g–1 and large pore volume (0.19 cm3g–1. Foron blue dye degradation over 3 wt% MoS2/ZnO nanocomposite was 254 times larger than that of mesoporous zinc oxide. Also, Foron blue dye degradation over 3 wt% MoS2/ZnO nanocomposite was 1.8 and 1.2 times greater than that of 0.5 wt% MoS2/ZnO and 1 wt% MoS2/ZnO nanocomposite, respectively. The increased Foron blue dye degradation by increase wt% of MoS2, due to increased separation of charge carrier and high capacity of light-harvesting. Moreover, high foron blue dye degradation was due to formation of a heterostructure between ZnO and MoS2, which accelerated charge carrier separation and improved degradation efficiency. The XPS and HRTEM results revealed that the MoS2 nanoparticles were deposited on the ZnO surface.

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Ha, Enna, Zongyuan Xin, Danyang Li, Jingge Zhang, Tao Ji, Xin Hu, Luyang Wang, and Junqing Hu. "Dual-Modified Cu2S with MoS2 and Reduced Graphene Oxides as Efficient Photocatalysts for H2 Evolution Reaction." Catalysts 11, no. 11 (October 22, 2021): 1278. http://dx.doi.org/10.3390/catal11111278.

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Noble metal-free cocatalysts have drawn great interest in accelerating the catalytic reactions of metal chalcogenide semiconductor photocatalyst. In particular, great efforts have been made on modifying a semiconductor with dual cocatalysts, which show synergistic effect of a fast transfer of exciton and energy simultaneously. Herein, we report the dual-modified Cu2S with MoS2 and reduced graphene oxides (Cu2S-MoS2/rGO). The in situ growth of Cu2S nanoparticles in the presence of MoS2/rGO resulted in high density of nanoscale interfacial contacts among Cu2S nanoparticles, MoS2, and rGO, which is beneficial for reducing the photogenerated electrons’ and holes’ recombination. The Cu2S-MoS2/rGO system also demonstrated stable photocatalytic activity for H2 evolution reaction for the long term.

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Li, Dikun, Hua Lu, Yangwu Li, Shouhao Shi, Zengji Yue, and Jianlin Zhao. "Plasmon-enhanced photoluminescence from MoS₂ monolayer with topological insulator nanoparticle." Nanophotonics 11, no. 5 (January 21, 2022): 995–1001. http://dx.doi.org/10.1515/nanoph-2021-0685.

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Abstract Topological insulators (TI), as a kind of fantastic nanomaterial with excellent electrical and optical properties, have attracted particular attention due to the promising applications in optoelectronic devices. Herein, we experimentally demonstrated the interaction between light and molybdenum disulfide (MoS2) monolayer with an antimony telluride (Sb2Te3) TI nanoparticle. It was found that photoluminescence (PL) emission and Raman scattering signal can be boosted by 5 and 8 folds in MoS2 monolayer integrated with the TI nanoparticle, respectively. The measured and simulated dark-field scattering spectra illustrated that the enhancement of light–matter interaction could be derived from the generation of localized surface plasmons on the TI nanoparticle with distinctly boosted electric field. We also found that there exists a redshift of 5 nm for the enhanced PL peak, which could be attributed to the formation of trions in MoS2 induced by plasmon doping. This work would provide a new pathway for the applications of TI nanoparticles in the optoelectronics, especially light–matter interaction enhancement.

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Verma, Dinesh, Nivedita Shukla, Bharat Kumar, Alok Singh, Kavita Shahu, Mithilesh Yadav, Kyong Rhee, and Rashmi Rastogi. "Synergistic Tribo-Activity of Nanohybrids of Zirconia/Cerium-Doped Zirconia Nanoparticles with Nano Lamellar Reduced Graphene Oxide and Molybdenum Disulfide." Nanomaterials 10, no. 4 (April 8, 2020): 707. http://dx.doi.org/10.3390/nano10040707.

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Zirconia and 10%, 20%, and 30% cerium-doped zirconia nanoparticles (ZCO), ZCO-1, ZCO-2, and ZCO-3, respectively, were prepared using auto-combustion method. Binary nanohybrids, ZrO2@rGO and ZCO-2@rGO (rGO = reduced graphene oxide), and ternary nanohybrids, ZrO2@rGO@MoS2 and ZCO-2@rGO@MoS2, have been prepared with an anticipation of a fruitful synergic effect of rGO, MoS2, and cerium-doped zirconia on the tribo-activity. Tribo-activity of these additives in paraffin oil (PO) has been assessed by a four-ball lubricant tester at the optimized concentration, 0.125% w/v. The tribo-performance follows the order: ZCO-2@rGO@MoS2 > ZrO2@rGO@MoS2 > ZCO-2@rGO > ZrO2@rGO > MoS2 > ZrO2 > rGO > PO. The nanoparticles acting as spacers control restacking of the nanosheets provided structural augmentation while nanosheets, in turn, prevent agglomeration of the nanoparticles. Doped nanoparticles upgraded the activity by forming defects. Thus, the results acknowledge the synergic effect of cerium-doped zirconia and lamellar nanosheets of rGO and MoS2. There is noncovalent interaction among all the individuals. Analysis of the morphological features of wear-track carried out by scanning electron microscopy (SEM) and atomic force microscopy (AFM) in PO and its formulations with various additives is consistent with the above sequence. The energy dispersive X-ray (EDX) spectrum of ZCO-2@rGO@MoS2 indicates the existence of zirconium, cerium, molybdenum, and sulfur on the wear-track, confirming, thereby, the active role played by these elements during tribofilm formation. The X-ray photoelectron spectroscopy (XPS) studies of worn surface reveal that the tribofilm is made up of rGO, zirconia, ceria, and MoS2 along with Fe2O3, MoO3, and SO42− as the outcome of the tribo-chemical reaction.

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Li, Tingting, Zhuhong Wang, Chaochao Liu, Chunmin Tang, Xinkai Wang, Gongsheng Ding, Yichun Ding, and Lixia Yang. "TiO2 Nanotubes/Ag/MoS2 Meshy Photoelectrode with Excellent Photoelectrocatalytic Degradation Activity for Tetracycline Hydrochloride." Nanomaterials 8, no. 9 (August 27, 2018): 666. http://dx.doi.org/10.3390/nano8090666.

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A novel type of TiO2 nanotubes (NTs)/Ag/MoS2 meshy photoelectrode was fabricated with highly oriented TiO2 nanotube arrays grown from a Ti mesh supporting Ag nanoparticles and three-dimensional MoS2 nanosheets. In this structure, Ag nanoparticles act as bridges to connect MoS2 and TiO2 and pathways for electron transfer, ensuring the abundant production of active electrons, which are the source of •O2−. The TiO2 NTs/Ag/MoS2 mesh can be used as both photocatalyst and electrode, exhibiting enhanced photoelectrocatalytic efficiency in degrading tetracycline hydrochloride under visible light irradiation (λ ≥ 420 nm). Compared to unmodified TiO2 NTs, the improved photoelectrocatalytic activity of the TiO2 NTs/Ag/MoS2 arise from the formation of Z-scheme heterojunctions, which facilitate the efficient separation of photogenerated electron-hole pairs through the Schottky barriers at the interfaces of TiO2 NTs–Ag and Ag–MoS2.

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Drozdov, AD, and J. deClaville Christiansen. "Modeling dielectric permittivity of polymer composites filled with transition metal dichalcogenide nanoparticles." Journal of Composite Materials 54, no. 25 (May 1, 2020): 3841–55. http://dx.doi.org/10.1177/0021998320922601.

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A model is developed for the dielectric permittivity of polymer nanocomposites reinforced with transition metal dichalcogenide fillers at microwave frequencies. The model takes into account aggregation of nanoparticles into clusters (that involve both filler and matrix components) and the aspect ratio of aggregates. The governing equations involve four material parameters that are found by matching observations on the real and imaginary parts of the dielectric permittivity of polymers reinforced with MoS2 and WS2 micro- and nanospheres, MoS2 nanosheets and nanoflowers, and composite heterostructures formed by MoS2 and MoS2-CoS2 nanoparticles with graphene and reduced graphene oxide. Good agreement is demonstrated between results of simulation and the experimental data at frequencies in the S, X, and Ku bands of the electromagnetic spectrum. It is shown that composite heterostructures have superior dielectric properties compared with those of neat transition metal dichalcogenide nanoparticles.

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29

An, Vladimir, Herman Potgieter, Natalia Usoltseva, Damir Valiev, Sergei Stepanov, Alexey Pustovalov, Arsenii Baryshnikov, Maksim Titov, and Alesya Dolinina. "MoS2@ZnO Nanoheterostructures Prepared by Electrospark Erosion for Photocatalytic Applications." Nanomaterials 11, no. 1 (January 9, 2021): 157. http://dx.doi.org/10.3390/nano11010157.

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MoS2@ZnO nanoheterostructures were synthesized by electrospark erosion of zinc granules in a hydrogen peroxide solution and simultaneous addition of MoS2 nanostructured powder into the reaction zone. The morphology, size of the crystallites, as well as elemental and phase composition of the prepared structures, were examined using transmission electron microscopy and X-ray diffraction analysis. It was found that the synthesized products represent heterostructures containing MoS2 nanoparticles formed on ZnO nanoparticles. Raman spectroscopy and photoluminescence analysis were also used for characterization of the prepared heterostructures. The obtained MoS2@ZnO nanostructures revealed an intense broad emission band ranging from 425 to 625 nm for samples with different fractions of MoS2. Photocatalytic measurements showed that the maximal hydrogen evolution rate of the prepared nanoheterostructures was about 906.6 μmol·g−1·h−1. The potential of their application in photocatalytic water splitting was also estimated.

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30

An, Vladimir, Herman Potgieter, Natalia Usoltseva, Damir Valiev, Sergei Stepanov, Alexey Pustovalov, Arsenii Baryshnikov, Maksim Titov, and Alesya Dolinina. "MoS2@ZnO Nanoheterostructures Prepared by Electrospark Erosion for Photocatalytic Applications." Nanomaterials 11, no. 1 (January 9, 2021): 157. http://dx.doi.org/10.3390/nano11010157.

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MoS2@ZnO nanoheterostructures were synthesized by electrospark erosion of zinc granules in a hydrogen peroxide solution and simultaneous addition of MoS2 nanostructured powder into the reaction zone. The morphology, size of the crystallites, as well as elemental and phase composition of the prepared structures, were examined using transmission electron microscopy and X-ray diffraction analysis. It was found that the synthesized products represent heterostructures containing MoS2 nanoparticles formed on ZnO nanoparticles. Raman spectroscopy and photoluminescence analysis were also used for characterization of the prepared heterostructures. The obtained MoS2@ZnO nanostructures revealed an intense broad emission band ranging from 425 to 625 nm for samples with different fractions of MoS2. Photocatalytic measurements showed that the maximal hydrogen evolution rate of the prepared nanoheterostructures was about 906.6 μmolg−1h−1.The potential of their application in photocatalytic water splitting was also estimated.

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Jing, Yuting, Ruijing Wang, Qiang Wang, and Xuefeng Wang. "Gold Nanoclusters Grown on MoS2 Nanosheets by Pulsed Laser Deposition: An Enhanced Hydrogen Evolution Reaction." Molecules 26, no. 24 (December 11, 2021): 7503. http://dx.doi.org/10.3390/molecules26247503.

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Au nanoparticles were decorated on a 2H MoS2 surface to form an Au/MoS2 composite by pulse laser deposition. Improved HER activity of Au/MoS2 is evidenced by a positively shifted overpotential (−77 mV) at a current density of −10 mA cm−2 compared with pure MoS2 nanosheets. Experimental evidence shows that the interface between Au and MoS2 provides more sites to combine protons to form an active H atom. The density functional theory calculations found that new Au active sites on the Au and MoS2 interface with improved conductivity of the whole system are essential for enhancing HER activity of Au/MoS2.

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32

Poudel, Yuba, Sairaman Seetharaman, Swastik Kar, Francis D’Souza, and Arup Neogi. "Plasmon-Induced Enhanced Light Emission and Ultrafast Carrier Dynamics in a Tunable Molybdenum Disulfide-Gallium Nitride Heterostructure." Materials 15, no. 21 (October 22, 2022): 7422. http://dx.doi.org/10.3390/ma15217422.

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The effect of localized plasmon on the photoemission and absorption in hybrid molybdenum disulfide-Gallium nitride (MoS2-GaN) heterostructure has been studied. Localized plasmon induced by platinum nanoparticles was resonantly coupled to the bandedge states of GaN to enhance the UV emission from the hybrid semiconductor system. The presence of the platinum nanoparticles also increases the effective absorption and the transient gain of the excitonic absorption in MoS2. Localized plasmons were also resonantly coupled to the defect states of GaN and the exciton states using gold nanoparticles. The transfer of hot carriers from Au plasmons to the conduction band of MoS2 and the trapping of excited carriers in MoS2 within GaN defects results in transient plasmon-induced transparency at ~1.28 ps. Selective optical excitation of the specific resonances in the presence of the localized plasmons can be used to tune the absorption or emission properties of this layered 2D-3D semiconductor material system.

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Deepak, Francis Leonard, Rodrigo Esparza, Carlos Fernando Castro-Guerrero, Sergio Mejía-Rosales, Xochitl Lopez-Lozano, and Miguel Jose-Yacaman. "Insights into the Structure of MoS2/WS2 Nanomaterial Catalysts as Revealed by Aberration Corrected STEM." Microscopy and Microanalysis 18, S5 (August 2012): 65–66. http://dx.doi.org/10.1017/s1431927612012986.

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Molybdenum disulfide/Tungsten disulphide (MoS2/WS2) is a compound very useful for its properties; it is used as lubricant, catalyst in hydrodesulfuration, in hydrogen fuel storage, etc. As part of the 2nd Joint Congress of the Portuguese and Spanish Microscopy Societies the present work reports about the different types of MoS2/WS2 nanomaterials which have been investigated by using aberration corrected STEM namely: (1) MoS2 nanotubes (2) MoS2 hexagonal nanoplates, (3) rippled or helical MoS2 nanowires, (4) Co-doped MoS2/WS2 nanowires and (5) fullerene-like WS2 nanoparticles.

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34

Nagarajan, Thachnatharen, Mohammad Khalid, Nanthini Sridewi, Priyanka Jagadish, and Rashmi Walvekar. "Microwave Synthesis of Molybdenum Disulfide Nanoparticles Using Response Surface Methodology for Tribological Application." Nanomaterials 12, no. 19 (September 27, 2022): 3369. http://dx.doi.org/10.3390/nano12193369.

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We used response surface methodology (RSM) based on the central composite design (CCD) model to optimize the synthesis time and temperature of the molybdenum disulfide (MoS2) nanoparticles using the flexiWAVE microwave. Furthermore, the synthesized MoS2 nanoparticles were used in SAE 20W50 diesel engine oil to study the tribological properties according to ASTM standards using a four-ball tribotester. The optimization result shows that the synthesis temperature and time for the MoS2 nanoparticles in the microwave were ~200 °C and ~15 min, respectively, with a coefficient of friction (COF) and average wear scar diameter (WSD) of 0.0849 and 320 μm. Furthermore, the difference between the experimental and predicted values was minimal (1.88% (COF) and 0.625% (WSD)), which was similar to the optimization model.

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Mei, Liang, Xiaoping Gao, Zhan Gao, Qingyong Zhang, Xinge Yu, Andrey L. Rogach, and Zhiyuan Zeng. "Size-selective synthesis of platinum nanoparticles on transition-metal dichalcogenides for the hydrogen evolution reaction." Chemical Communications 57, no. 23 (2021): 2879–82. http://dx.doi.org/10.1039/d0cc08091h.

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Pt-MoS2 composites are fabricated via growing tunable Pt nanoparticles size (NPs, 2–6 nm) on single-layer MoS2 nanosheets. Which have shown excellent performance for hydrogen evolution reaction (HER) with the Pt NPs exhibiting a volcano-type size effect toward mass activity due to the synergistic effects between the Pt NPs and MoS2.

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Bojarska, Zuzanna, Marta Mazurkiewicz-Pawlicka, Stanisław Gierlotka, and Łukasz Makowski. "Production and Properties of Molybdenum Disulfide/Graphene Oxide Hybrid Nanostructures for Catalytic Applications." Nanomaterials 10, no. 9 (September 17, 2020): 1865. http://dx.doi.org/10.3390/nano10091865.

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Molybdenum disulfide (MoS2) can be an excellent candidate for being combined with carbon nanomaterials to obtain new hybrid nanostructures with outstanding properties, including higher catalytic activity. The aim of the conducted research was to develop the novel production method of hybrid nanostructures formed from MoS2 and graphene oxide (GO). The nanostructures were synthesized in different weight ratios and in two types of reactors (i.e., impinging jet and semi-batch reactors). Physicochemical analysis of the obtained materials was carried out, using various analytical techniques: particle size distribution (PSD), thermogravimetric analysis (TGA), FT-IR spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). Due to the potential application of materials based on MoS2 as the catalyst for hydrogen evolution reaction, linear sweep voltammetry (LSV) of the commercial MoS2, synthesized MoS2 and the obtained hybrid nanostructures was performed using a three-electrode system. The results show that the developed synthesis of hybrid MoS2/GO nanostructures in continuous reactors is a novel and facile method for obtaining products with desired properties. The hybrid nanostructures have shown better electrochemical properties and higher onset potentials compared to MoS2 nanoparticles. The results indicate that the addition of carbon nanomaterials during the synthesis improves the activity and stability of the MoS2 nanoparticles.

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XU, W., Y. FU, W. YAN, Y. XU, M. XUE, and J. XU. "TiO2 NANOPARTICLES DECORATED FLOWER-LIKE MoS2 NANOSPHERES WITH ENLARGED INTERLAYER SPACING OF (002) PLANE FOR ENHANCED TRIBOLOGICAL PROPERTIES." Digest Journal of Nanomaterials and Biostructures 16, no. 1 (January 2021): 81–91. http://dx.doi.org/10.15251/djnb.2021.161.81.

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In this work, TiO2@MoS2 heterojunction of TiO2 nanoparticles decorated MoS2 nanospheres were successfully fabricated by one-step hydrothermal approach using TiO2 as the precursor, and systematically investigated by various characterization methods (e.g. XRD, SEM, TEM and XPS analysis). Moreover, the tribological experiments of liquid paraffin contained TiO2, MoS2, and TiO2@MoS2 nano-additives were comparatively investigated by a ball-plate wear instrument, which tribological variables include applied load and rotational speed. TiO2@MoS2 as an additive in base oil exhibited superior antifriction and wear resistant among various nano-additives. At the optimal conditions, 5%-TiO2@MoS2-paraffin samples show the lower friction coefficient (~0.08) compared with pure paraffin, and paraffin contained TiO2 and/or MoS2. Additionally, the excellent anti-friction and wear-resistant of TiO2@MoS2 in base oil would be beneficial for the design of novel MoS2-based nano-additives for improving tribological performance in the industry and agriculture.

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Malagrino, Thiago R. S., Anna P. Godoy, Juliano M. Barbosa, Abner G. T. Lima, Nei C. O. Sousa, Jairo J. Pedrotti, Pamela S. Garcia, et al. "Multifunctional Hybrid MoS2-PEGylated/Au Nanostructures with Potential Theranostic Applications in Biomedicine." Nanomaterials 12, no. 12 (June 15, 2022): 2053. http://dx.doi.org/10.3390/nano12122053.

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In this work, flower-like molybdenum disulfide (MoS2) microspheres were produced with polyethylene glycol (PEG) to form MoS2-PEG. Likewise, gold nanoparticles (AuNPs) were added to form MoS2-PEG/Au to investigate its potential application as a theranostic nanomaterial. These nanomaterials were fully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), photoelectron X-ray spectroscopy (XPS), Fourier-transformed infrared spectroscopy (FTIR), cyclic voltammetry and impedance spectroscopy. The produced hierarchical MoS2-PEG/Au microstructures showed an average diameter of 400 nm containing distributed gold nanoparticles, with great cellular viability on tumoral and non-tumoral cells. This aspect makes them with multifunctional characteristics with potential application for cancer diagnosis and therapy. Through the complete morphological and physicochemical characterization, it was possible to observe that both MoS2-PEG and MoS2-PEG/Au showed good chemical stability and demonstrated noninterference in the pattern of the cell nucleus, as well. Thus, our results suggest the possible application of these hybrid nanomaterials can be immensely explored for theranostic proposals in biomedicine.

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Yanilmaz, Meltem, and Jung Joong Kim. "Flexible MoS2 Anchored on Ge-Containing Carbon Nanofibers." Nanomaterials 13, no. 1 (December 23, 2022): 75. http://dx.doi.org/10.3390/nano13010075.

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Germanium is a promising anode material for sodium-ion batteries (SIBs) because of its high theoretical specific capacity, high ion diffusivity, and rate capability. However, large volume changes and pulverization deteriorate the cycling performance. In this study, flexible electrospun germanium/carbon nanofibers (Ge/CNFs) were prepared via electrospinning followed by heat treatment. MoS2 nanoparticles were subsequently anchored on the flexible Ge/CNFs via hydrothermal synthesis. Flexible MoS2 anchored on Ge/CNFs (MoS2@Ge/CNFs) was used as a self-standing binder-free anode in an SIB. Because of the high electronic conductivity of CNFs and the many active sites of MoS2 nanoparticles, a high initial capacity of over 880 mAh/g was achieved at a current density of 0.1 A/g. Moreover, the flexible binder-free MoS2@Ge/CNFs exhibited an excellent C-rate performance with a reversible capacity of over 300 mAh/g at a current density of 2 A/g. Therefore, we demonstrated that flexible binder-free MoS2@Ge/CNFs are a promising electrode candidate for a high-performance rechargeable battery.

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Santalucia, Rosangela, Paolo Negro, Tiziano Vacca, Francesco Pellegrino, Alessandro Damin, Federico Cesano, and Domenica Scarano. "In Situ Assembly of Well-Defined MoS2 Slabs on Shape-Tailored Anatase TiO2 Nanostructures: Heterojunctions Role in Phenol Photodegradation." Catalysts 12, no. 11 (November 11, 2022): 1414. http://dx.doi.org/10.3390/catal12111414.

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MoS2/TiO2-based nanostructures have attracted extensive attention due to their high performance in many fields, including photocatalysis. In this contribution, MoS2 nanostructures were prepared via an in situ bottom-up approach at the surface of shape-controlled TiO2 nanoparticles (TiO2 nanosheets and bipyramids). Furthermore, a multi-technique approach by combining electron microscopy and spectroscopic methods was employed. More in detail, the morphology/structure and vibrational/optical properties of MoS2 slabs on TiO2 anatase bipyramidal nanoparticles, mainly exposing {101} facets, and on TiO2 anatase nanosheets exposing both {001} and {101} facets, still covered by MoS2, were compared. It was shown that unlike other widely used methods, the bottom-up approach enabled the atomic-level growth of well-defined MoS2 slabs on TiO2 nanostructures, thus aiming to achieve the most effective chemical interactions. In this regard, two kinds of synergistic heterojunctions, namely, crystal face heterojunctions between anatase TiO2 coexposed {101} and {001} facets and semiconductor heterojunctions between MoS2 and anatase TiO2 nanostructures, were considered to play a role in enhancing the photocatalytic activity, together with a proper ratio of (101), (001) coexposed surfaces.

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Gholinia, Mosayeb, Aliakbar Ranjbar, Mohammad Javidan, and Aliakbar Hosseinpour. "Effect of two different nano-particles (GO-MoS₂) and a new micro-sprayer model on power electronic module for thermal management." Advances in Mechanical Engineering 14, no. 5 (May 2022): 168781322210875. http://dx.doi.org/10.1177/16878132221087512.

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In this work, we have studied the performance of the cooling system with the presence of graphene oxide (GO) and molybdenum sulfide (MoS2) nanoparticles to reduce heat stress, increase the final efficiency, and maintain the reliability of Diode and IGBT electronic module. Beyond the geometric design of micro-sprays and dimensional changes, as well as the type of cooling fluid effect, the use of nanofluids for the purpose of thermal management of electronic systems will be an interesting and effective innovation. In the simulation parameters, the dimensional ratio of micro-sprays, the rate of cooling flows, and the volume fraction of nanoparticles were investigated. According to the results, considering the spray of the BSM-4N model and the input mass rate of 0.04 kg/s, by increasing the volume fraction of nanoparticles from 0.01 to 0.05, the heat transfer of nanofluid increases, thus leading to an increase in thermal efficiency. In this paper, the thermal effects of GO nanoparticle were significantly more favorable than those of MoS2 nanoparticle. In addition, it was found that by reducing the spray nozzle using installing the blade and simultaneous use of GO nanofluid with volume fraction of 0.05, the temperature inside the module is reduced below 323 K.

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JOTHIRAMALINGAM, R., H. A. AL-LOHEDAN, D. M. AL-DHAYAN, and M. D. WASMIAH. "PREPARATION AND STRUCTURAL CHARACTERIZATION OF MoS2 NANOPARTICLE COATED GRAPHENE OXIDE/MANGANESE OXIDE COMPOSITE FOR ENERGY STORAGE APPLICATION." Chalcogenide Letters 17, no. 4 (April 2020): 217–22. http://dx.doi.org/10.15251/cl.2020.174.217.

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Nanoparticles of powder molybdenum sulphide (MoS2) are deposited on reduced graphene oxide-mesoporous manganese oxide nanocomposite which is represented as MoSGMn were prepared by feasible ultrasonic assisted deposition technique. The above prepared nanocomposite is further coated on Nickel foam substrate for direct application towards supercapacitor electrode fabrication. The detailed studies of thermal property and surface property such as thermal stability, surface structure and zeta potential measurements have been explained for all prepared nanocomposite samples. The thermal stability of as prepared sample stable upto 350 oC in oxygen atmosphere and negative zeta potential obtained for all prepared nanocomposite sample. The different amount of MoS2 nanoparticle (10mg -100 mg range) was utilized to study the effect of molybdenum sulphide addition on major mesoporous manganese oxide matrix. Increased quantity of MoS2 addition increase the electrochemical supercapacitance value of the nanocomposite coated nickel foam modified electrode.

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Boychuk, V. M., L. O. Shyyko, V. O. Kotsyubynsky, and A. Kachmar. "Structure and morphology of MoS2 / Carbon nanocomposite materials." Фізика і хімія твердого тіла 20, no. 1 (April 1, 2019): 63–68. http://dx.doi.org/10.15330/pcss.20.1.68.

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The paper presents the experimental results of the hydrothermal synthesis composite materials based on the MoS2 and carbon using different types of detergents (cetyltrimethylammonium bromide and Triton-X) or microporous carbon. The synthesized material was studied by XRD, TEM, and EDS. The investigation of structural and morphological properties of the obtained nanocomposite material shows that the nanoparticles (the average size of about 40 nm) obtained by detergent-assisted procedure have a multilayer crystal ordered superficial layers where quasi-two-dimensional MoS2 layers alternate with amorphous carbon. The annealing at 500oC in argon caused the formation turbostratically stacked layers of crystalline MoS2 with amorphous carbon located in the interlayer space. The core-shall morphology (carbon nanoparticles on the surface of MoS2 clusters) was observed for composite materials synthesized on the base of microporous carbon.

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Khan, Ramsha, Adeel Riaz, Sofia Javed, Rahim Jan, Muhammad Aftab Akram, and Mohammad Mujahid. "Synthesis and Characterization of MoS₂/TiO₂ Nanocomposites for Enhanced Photocatalytic Degradation of Methylene Blue under Sunlight Irradiation." Key Engineering Materials 778 (September 2018): 137–43. http://dx.doi.org/10.4028/www.scientific.net/kem.778.137.

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2D nanosheets/ nanoparticles based MoS2/TiO2 nanocomposites were prepared in different weight compositions which were further employed to investigate photocatalytic degradation of methylene blue. Anatase TiO2 powder was prepared via sol-gel reflux method using titanium tetraisopropoxide as Ti precursor. MoS2/TiO2 nanocomposites were prepared by in situ addition of exfoliated MoS2 (2D-nanosheets) in different weight ratios of 0.1%, 0.5%, 1%, 2% and 5% in TiO2 sol. Surface morphology, phase analysis, optical properties were studied using SEM, XRD, UV-Vis spectroscopy respectively. SEM results showed that TiO2 nanoparticles were completely adsorbed over the surface of MoS2 sheets as reflux synthesis was employed. Efficient charge carrier separation was achieved which reduced recombination, and hence, enhanced photo-degradation of methylene blue was observed. The hetero-structures showed less operation time in sunlight for photodegradation of methylene blue and a highest rate constant was observed by 2 wt.% loading of MoS2 on TiO2. These composites can also be used commercially as they show promising results.

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Chen, Kangmin, Wei Jiang, Xianghong Cui, and Shuqi Wang. "Effect of nanoparticles on the tribo-layers and the tribology of a steel-on-steel couple." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 233, no. 1 (March 25, 2018): 30–40. http://dx.doi.org/10.1177/1350650118765005.

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The tribological behavior and tribo-layers of AISI 1045 steel sliding against 52100 steel were investigated in the case of supplying MoS2, Fe2O3, and their mixtures onto the sliding interface. When nanoparticles were supplied, tribo-layers were formed on the worn surfaces. The tribological behavior of the sliding pair depended on the characteristics of tribo-layers, which were decided by different nanoparticles. As the additives—especially the ones containing MoS2—were supplied onto the sliding interface, the wear rates and friction coefficients of both 1045 steel and 52100 steel were markedly decreased to extremely low values, approaching zero and marginally undulated with the increase in load. Single-component Fe2O3 nanoparticles markedly reduced the wear rate of 1045 steel with slightly increased friction coefficient, but its decreased extent was merely half of that of the additives containing MoS2. The improvement of the tribological performance of steels was attributed to the formation of protective tribo-layers. The addition of pure Fe2O3 resulted in the formation of insert-type tribo-layers, while cover-type tribo-layers were formed by the addition of the mixture additives of Fe2O3+MoS2 and pure MoS2. The cover-type tribo-layers provided more protective and lubricative functions than that of the insert-types.

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Bai, Xiaoyan, Tianqi Cao, Tianyu Xia, Chenxiao Wu, Menglin Feng, Xinru Li, Ziqing Mei, et al. "MoS2/NiSe2/rGO Multiple-Interfaced Sandwich-like Nanostructures as Efficient Electrocatalysts for Overall Water Splitting." Nanomaterials 13, no. 4 (February 16, 2023): 752. http://dx.doi.org/10.3390/nano13040752.

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Constructing a heterogeneous interface using different components is one of the effective measures to achieve the bifunctionality of nanocatalysts, while synergistic interactions between multiple interfaces can further optimize the performance of single-interface nanocatalysts. The non-precious metal nanocatalysts MoS2/NiSe2/reduced graphene oxide (rGO) bilayer sandwich-like nanostructure with multiple well-defined interfaces is prepared by a simple hydrothermal method. MoS2 and rGO are layered nanostructures with clear boundaries, and the NiSe2 nanoparticles with uniform size are sandwiched between both layered nanostructures. This multiple-interfaced sandwich-like nanostructure is prominent in catalytic water splitting with low overpotential for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) and almost no degradation in performance after a 20 h long-term reaction. In order to simulate the actual overall water splitting process, the prepared nanostructures are assembled into MoS2/NiSe2/rGO||MoS2/NiSe2/rGO modified two-electrode system, whose overpotential is only 1.52 mV, even exceeded that of noble metal nanocatalyst (Pt/C||RuO2~1.63 mV). This work provides a feasible idea for constructing multi-interface bifunctional electrocatalysts using nanoparticle-doped bilayer-like nanostructures.

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Saboor, Khalid, Jan, Khan, Farooq, Afridi, Sadiq, and Arif. "PS/PANI/MoS2 Hybrid Polymer Composites with High Dielectric Behavior and Electrical Conductivity for EMI Shielding Effectiveness." Materials 12, no. 17 (August 22, 2019): 2690. http://dx.doi.org/10.3390/ma12172690.

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Liquid exfoliated molybdenum disulfide (MoS2) nanosheets and polyaniline (PANI) nanoparticles are dispersed in polystyrene (PS) matrix to fabricate hybrid polymer composites with high dielectric and electromagnetic interference (EMI) shielding behavior. A phase-separated morphology is formed when PANI and MoS2 are incorporated into polystyrene (PS) matrix. An increasing concentration of MoS2 nanoparticles inside PS/PANI (5 wt %) polymer blend forms an interconnected network, resulting in high electrical conductivity and dielectric behavior, making them a suitable candidate for EMI shielding application. An increment in dielectric constant and loss, up to four and five orders of magnitude, respectively, is recorded at a maximum concentration of 1 wt % of MoS2 in PS/PANI-5 polymer blend at 100 Hz. The enhanced dielectric characteristics for PS/PANI/MoS2 composites are then theoretically evaluated for the estimation of EMI shielding effectiveness in the frequency range of 100 Hz to 5 MHz. The maximum dielectric constant and loss achieved for PS/PANI-5 wt %/MoS2-1 wt % are responsible for estimated shielding effectiveness of around 92 dB at 100 Hz. The increase in dielectric behavior and shielding effectiveness is probably due to the increased number of charged dipoles accumulated at the insulator–conductor interface.

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Duc, Tran Minh, Tran The Long, and Tran Quyet Chien. "Performance Evaluation of MQL Parameters Using Al2O3 and MoS2 Nanofluids in Hard Turning 90CrSi Steel." Lubricants 7, no. 5 (May 8, 2019): 40. http://dx.doi.org/10.3390/lubricants7050040.

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Hard machining has gained much attention to be an alternative solution for many traditional finish grinding operations due to high productivity, ease to adapt to complex part contours, the elimination of cutting fluids, good surface quality, and the reduction of machine tool investment. However, the enormous amount of heat generated from the cutting zone always requires the high-grade inserts and limits the cutting conditions. The MQL technique with nanofluids assisted for hard machining helps to improve the cutting performance while ensuring environmentally friendly characteristics. This paper focuses on the development of MQL technique by adding Al2O3 and MoS2 nanoparticles to the base fluids (soybean oil and water-based emulsion) for the hard turning of 90CrSi steel (60÷62 HRC). The analysis of variance (ANOVA) is used to evaluate the performance of MQL parameters in terms of cutting forces and surface roughness. The study reveals that a better performance of coated carbide inserts is observed by using MQL with Al2O3 and MoS2 nanofluids. In addition, the fluid type, nanoparticles and nanoparticle concentration have a strong effect on cutting performance. The interaction influence among the investigated variables is also studied in order to provide the technical guides for further studies using Al2O3 and MoS2 nanofluids.

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Ma, Lin, Xiaoping Zhou, Limei Xu, Xuyao Xu, and Lingling Zhang. "Microwave-Assisted Hydrothermal Preparation of SnO2/MoS2 Composites and their Electrochemical Performance." Nano 11, no. 02 (February 2016): 1650023. http://dx.doi.org/10.1142/s1793292016500235.

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We introduce a two-step hydrothermal and microwave method to prepare novel SnO2/MoS2 composites. The as-prepared samples are well characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). The experimental results indicate that the SnO2/MoS2 composites are composed of MoS2 nanosheets and ultrafine SnO2 nanoparticles with mean size of 3–4[Formula: see text]nm which are well-distributed and anchored on the surface of MoS2 nanosheets. The resultant composites demonstrate prominently improved electrochemical performances, which could be attributed to the unique and robust microstructures and synergetic effect between MoS2 and SnO2.

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Zhang, Jie, Yamin Yang, and Zhiyu Qian. "Inherent Electrochemical Properties of MoS2 Nanoparticles." Journal of Bionanoscience 11, no. 3 (June 1, 2017): 189–93. http://dx.doi.org/10.1166/jbns.2017.1438.

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Journal articles on the topic 'MoS2 Nanoparticles'

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