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Molybdenum disulfide (MoS2), a 2D layered structure, because of its unique properties has widely attracted many researchers. In this study, by employing physical and chemical methods, not only layers of MoS2 have been intercalated, but also their surface properties enhanced. Low-dimensional and potential properties of intercalated MoS2 nanosheets are the aim of many researches. Here, we report a novel four step method to intercalate the layers of MoS2 nanosheets successfully using acid treatment, sonication, oxidization and thermal shocking. The other goal in this study is to evaluate the cation exchange ability and anticorrosion performance of the Ce3+ doped MoS2 nanosheets. The... 

Due to high surface to volume ratio and tunable band gap, two dimensional (2D) layered materials such as MoS2, is good candidate for gas sensing applications. This research mainly focuses on variation of Density of States (DOS) of MoS2 monolayes caused by ethanol adsorption. The nanosheets are synthesized by liquid exfoliation, and then using Scanning Tunneling Spectroscopy (STS) and Density Functional Theory (DFT), local electronic characteristic such as DOS and band gap in non-vacuum condition are analyzed. The results show that ethanol adsorption enhances DOS and deform orbitals near the valence and conduction bands that increase transport of carriers on the sheet. © 2018 IOP Publishing... 

Lithium intercalation is a convenient method to prepare few-layer and single-layer MS2 (M=Mo, W) nanosheets. This method is, however, very time-consuming (few days) and it is difficult to control the reaction parameters. To overcome these drawbacks, we have proposed a method to use an Li battery set-up to significantly reduce the reaction time (few hours) and electrochemically intercalate lithium ions into MS2 layers in a controllable manner. Atomic force microscopy (AFM), scanning electron microscopy (SEM) and Raman spectroscopy results revealed that MoS2 and WS2 single-layer (thickness of ~ 1 nm) nanosheets with the 1T phase were prepared after intercalation in an Li battery set-up.... 

Lithium intercalation is a convenient method to prepare few-layer and single-layer MS2 (M=Mo, W) nanosheets. This method is, however, very time-consuming (few days) and it is difficult to control the reaction parameters. To overcome these drawbacks, we have proposed a method to use an Li battery set-up to significantly reduce the reaction time (few hours) and electrochemically intercalate lithium ions into MS2 layers in a controllable manner. Atomic force microscopy (AFM), scanning electron microscopy (SEM) and Raman spectroscopy results revealed that MoS2 and WS2 single-layer (thickness of ~ 1 nm) nanosheets with the 1T phase were prepared after intercalation in an Li battery set-up.... 

In present study, an efficient method was used to synthesis Au and Pt nanoparticles on Ni modified MoS2 (MNi/MoS2 (M = Au and Pt). The morphology and structure of the prepared products were characterized using different microscopic and spectroscopic methods. The as-synthesized MNi/MoS2 nanocomposites were applied for catalytic reduction of p-nitrophenol (P-NP) in the presence of NaBH4. P-NP is one of the prevalent contaminants in wastewaters, while its corresponding aromatic amine (4-aminophenol) is a precious intermediate for manufacturing of important materials such as pharmaceuticals. The obtained catalytic results indicated that noble metal nanoparticles significantly affect catalytic... 

Single-layer MoS2-MoO3-x heterojunction nanosheets with visible-light-sensitive band gap energy and average lateral dimensions of ~70 nm were synthesized by using a two-step combined exfoliation method. The exfoliation was initiated from pristine MoS2, while some sulfur sites in expanded MoS2 sheets during exfoliating were substituted by ambient non-thermal oxygen, resulting in formation of α-MoO3-x crystalline domains. The morphological features, crystalline structure, phase formation, number of layers, and optical properties of the MoS2-MoO3-x nanosheets were determined by atomic force microscopy; X-ray diffraction; field emission electron microscopy; transmission electron microscopy; and... 

PEGylated MoS2 nanoflower (MoS2-NF) and nanosheet (MoS2-NS) are synthesized through a one-pot hydrothermal method as photo absorbing agent (PAA). It is found that employing different thiol precursors result in distinct morphologies. The products are structurally, chemically, and morphologically characterized. Electron microscopy demonstrates the formation of sheet and flower morphologies of MoS2. Fourier transform infrared (FTIR) and thermal gravimetric (TGA) analysis confirm the PEGylation of MoS2 nanostructures. Raman and X-ray photoelectron spectroscopy (XPS) confirm the formation of 1T/2H structure of both samples. MoS2-NS demonstrates higher NIR absorption than MoS2-NF with a mass... 

This article presents an applicable intuitive current-voltage model for long-channel transistors based on 2-D materials. This model carefully predicts the transistor behavior in the saturation and triode regions, which are important for analog and digital applications. Moreover, the effect of mobility degradation on the characteristics of the transistor is probed. As a case study, the developed model has been applied to a transistor with mono-layer MoS2 as the channel material. The excellent agreement with experimental data verifies the accuracy of the model. Finally, the introduced model has been utilized to design an amplifier, a differential pair, and a low-frequency common source mixer... 

The interactions between four different gas molecules (methanol, o-xylene, p-xylene and m-xylene) and Ni-decorated monolayer MoS2 were investigated by means of density functional computations to exploit its potential application as a gas sensor. The electronic properties of the Ni-decorated monolayer MoS2 and gas molecule (adsorbent–adsorbate properties) strongly depend on the Ni-decorated monolayer MoS2 structure and the molecular configuration of the adsorbate. The adsorption properties of volatile organic compound (VOC) molecules on Ni-decorated MoS2 has been studied taking into account the parameters such as adsorption energy, energy bandgap, density of states, and Mulliken charge... 

In this research, a novel graphene-supported catalyst was prepared through which, a simultaneous chemical exfoliation of graphite and MoS2 powder performed preparing a new composite species and evaluated for the hydrodesulfurization reaction of naphtha and no sulfidation pretreatment was performed upon the catalyst. Also, the influences of the operating parameters such as temperature, and liquid hourly space velocity on HDS conversion evaluated. (Chemical Equation Presented)  

The great promise of electrochemical water splitting for green and sustainable hydrogen fuel production has motivated researchers to strive for more efficient and low-cost catalysts based on non-precious metals. In this study, MoS2 nanoflowers decorated with CuCo2O4 were successfully synthesized, and their catalytic activities toward the electrochemical hydrogen evolution reaction (HER) in an alkaline medium were investigated. The composition, structure, and morphology of the as-synthesized catalysts were explored by various techniques such as FT-IR, XRD, BET, SEM, and TEM. To maximize the catalytic activity, the composition of the nanocomposites was systematically varied. Catalytic results... 

We study topological phase transitions and topological quantum field effect transistor in monolayer molybdenum disulfide (MoS2) using a two-band Hamiltonian model. Without considering the quadratic (q 2) diagonal term in the Hamiltonian, we show that the phase diagram includes quantum anomalous Hall effect, quantum spin Hall effect, and spin quantum anomalous Hall effect regions such that the topological Kirchhoff law is satisfied in the plane. By considering the q 2 diagonal term and including one valley, it is shown that MoS2 has a non-Trivial topology, and the valley Chern number is non-zero for each spin. We show that the wave function is (is not) localized at the edges when the q 2... 

Despite their potential applications, a limited number of studies for synthesizing vertical MoS2 nanoflakes especially via CVD have been reported so far, which generally involve tedious complex- and/or multi-step growth processes. In this study, direct synthesis of vertical MoS2 nanoflakes grown on the SiO2/Si substrate during a rapid sulfidation process by CVD method has been reported. Material characterization was performed using Raman spectroscopy, XRD and FE-SEM. The XRD results indicated the dominant phase of 2H–MoS2 within the synthesized layers. The characteristic distance between the two dominant peaks of E1 2g and A1g in the Raman spectra confirms the multi-layered structure for... 

A novel AC impedance study on three-dimensional hybrid structures of graphene sheets/MoS2 nanorose (GMS) toward ethanol vapor detection is presented in this work. These defective 3D hybrid porous structures are sensitive to the presence of different gases as a result of charge transfer with gas species, as well as a change in the effective capacitance of the system. The sensing behavior of the samples is investigated throughout time-dependent impedance measurement and electrochemical impedance spectroscopy (EIS). The sensor response is estimated at about 20% to 10 ppm ethanol vapor, with the response and recovery times about 3.2 s and 0.8 s, respectively. Sensing mechanism proposed to... 

Using a tight-binding approach and first-principles calculations combined with the nonequilibrium Green’s function method, the thermal spin transport in a zigzag molybdenum disulfide (MoS 2) nanoribbon in the proximity of a ferromagnetic insulator that induces a local exchange magnetic field in the center of the nanoribbon is investigated. It is found that a pure spin current and perfect spin Seebeck effect with zero charge current can be generated by applying a thermal gradient and local exchange magnetic field without a bias voltage near room temperature. Furthermore, it is shown that this nanoscale device can act as a spin Seebeck diode for the control of thermal and spin information in... 

The development of active and stable materials has great importance for the commercialization of nickel-zinc (Ni–Zn) batteries and hydrogen production. Transition metal sulfides have good theoretical properties for these applications. In this research, we present the synthesis and characterization of Ni3S2@MoS2 nanocatalyst and its hybrid with reduced graphene oxide (Ni3S2@MoS2-rGO). The capability of these materials is investigated as cathode material for Ni–Zn batteries and hydrogen evolution in alkaline media. In the case of Ni–Zn batteries, the assembled Ni3S2@MoS2-rGO//Zn battery shows a discharge capacity of 249.3 mAh g−1 with coulombic efficiency of 97.2%, showing a higher... 

Molybdenum disulfide (MoS2), a two-dimensional transition metal has a 2D layered structure and has recently attracted attention due to its novel catalytic properties. In this study, MoS2 has been successfully intercalated using chemical and physical intercalation techniques, while enhancing its surface properties. The final intercalated MoS2 is of many interests because of its low-dimensional and potential properties in in-situ catalysis. In this research, we report different methods to intercalate the layers of MoS2 successfully using acid-treatment, ultrasonication, oxidation and thermal shocking. The other goal of this study is to form S[dbnd]O bonds mainly because of expected enhanced... 

The aim of this work is to investigate the effect of molybdenum disulfide on tribological properties of Ultra-high-molecular-weight polyethylene (UHMWPE). UHMWPE/MoS2 nano-composites were prepared using in-situ polymerization and Ziegler-Natta catalytic system. Studies showed that, in order to obtain the optimum tribological properties, interlayer distance between nanosheets should be as high as possible. Therefore, the nanosheets were subjected to oxidation using the required oxidants followed by thermal shock and ultrasound. Fourier-transform infrared spectroscopy (FTIR) analysis was used to determine the formation of functional groups which indicate the formation of S═O bond in the... 

Recent research interest in two-dimensional (2D) materials has led to an emerging new group of materials known as transition metal dichalcogenides (TMDs), which have significant electrical, optical, and transport properties. MoS2 is one of the well-known 2D materials in this group, which is a semiconductor with controllable band gap based on its structure. The hydrothermal process is known as one of the scalable methods to synthesize MoS2 nanostructures. In this study, the gas sensing properties of flower-shaped MoS2 nanoflakes, which were prepared from molybdenum trioxide (MoO3) by a facile hydrothermal method, have been studied. Material characterization was performed using X-ray...