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Two-dimensional (2D) transition metal dichalcogenide (TMDC) monolayers exhibit unique physical properties, such as self-terminating surfaces, a direct bandgap, and near-unity photoluminescence (PL) quantum yield (QY), which make them attractive for electronic and optoelectronic applications. Surface charge transfer has been widely used as a technique to control the concentration of free charge in 2D semiconductors, but its estimation and the impact on the optoelectronic properties of the material remain a challenge. In this work, we investigate the optical properties of a WS2 monolayer under three different doping approaches: benzyl viologen (BV), potassium (K), and electrostatic doping. Owing to the excitonic nature of 2D TMDC monolayers, the PL of the doped WS2 monolayer exhibits redshift and a decrease in intensity, which is evidenced by the increase in trion population. The electron concentrations of 3.79 × 10 13   cm − 2 , 6.21 × 10 13   cm − 2 , and 3.12 × 10 12   cm − 2 were measured for WS2 monolayers doped with BV, K, and electrostatic doping, respectively. PL offers a direct and versatile approach to probe the doping effect, allowing for the measurement of carrier concentration in 2D monolayer semiconductors. [ABSTRACT FROM AUTHOR]

Two‐dimensional transition metal dichalcogenides (2D TMDCs) have gained significant attention from the scientific community due to their exceptional properties. Recently, the metal‐assisted exfoliation technique has emerged as a promising method for producing large‐area, high‐quality 2D monolayers. However, achieving strong adhesion between metal foil and substrate during the exfoliation process remains a major challenge, preventing successful exfoliation. To overcome this issue, this study explores the application of (3‐Aminopropyl)triethoxysilane (APTES) as an adhesion layer to substantially improve adhesion between the monolayers and hydrophilic substrates such as SiO2, allowing for a high yield of mm‐sized monolayers. Two sample sets, obtained from the same MoS2 crystal via gold‐assisted exfoliation with APTES‐treated substrates and from standard scotch tape exfoliation, are statistically compared. APTES significantly improves exfoliation performance, yielding larger monolayers compared to conventional methods. This improvement enables the effective exfoliation with the gold‐tape method, which otherwise results in no yield. Through Raman and photoluminescence characterization techniques, it is found that the flakes obtained from gold‐assisted exfoliation and APTES are comparable to those obtained by standard scotch‐tape exfoliation in terms of defects and optical properties, showing signatures of strain‐induced Raman shift and n‐type doping. [ABSTRACT FROM AUTHOR]

van der Waals heterostructure (vdWH) is an attractive technique to enhance the behavior of two-dimensional materials for designing viable products for electronic, spintronics and clean energy source application. Inspired by the recent synthesized of CrSSe monolayer, we have calculated the structural, electronic, Rashba parameters and photocatalytic properties of MoS 2 -CrXY (X≠Y S, Se, Te) vdWH by using density functional theory calculation. Two different model of MoS 2 -CrXY (X≠Y S, Se, Te) vdWH are presented due to the alternative order of chalcogen atom attached to MoS 2 layer. Phonon band structure, thermal stability and binding energies confirms, the most favorable stacking configuration is dynamically, thermal and energetically feasible. Indirect type-I (MoS 2 -CrXY (X≠Y S, Se)) and type-II (MoS 2 –CrSeTe) band alignment are observed in understudy vdWH. Large Rashba spin splitting is observed in model 2. Electrostatic potential and Bader charge analysis show charges are transferred from MoS 2 layer to CrXY layer, while the potential drop separate charge carrier (holes and electrons) at the interface. Work function and charge density difference are also calculated and presented. A red shift is observed in the position of excitonic peaks from model 1 to model 2. In last we investigated the performance of these vdWH for photocatalytic water splitting at pH = 0. Our results shows that MoS 2 -CrXY (X≠Y S, Se, Te) vdWH may be promising for future nanoelectronics, spintronics and photocatalytic water splitting. • JTMDCs having strong intrinsic dipole and efficient for spintronics applications. • We construct vdWH by vdW stacking of MoS 2 and CrXY monolayer. • Bader charge analysis confirm the charge transfer in these vdWH. • Imaginary part of dielectric function is calculated for understanding the optical properties. • Photocatalytic response confirms that, MoS 2 -CrXY vdWH can split water into O 2 / H 2 O and H + / H 2. [ABSTRACT FROM AUTHOR]

Combining transition metal dichalcogenides (TMDCs) and molecular semiconductors is an attractive route for forming van der Waals heterostructures with optoelectronic properties not found in either component. Herein, the strong p‐type molecular dopant, 1,3,4,5,7,8‐hexafluoro‐tetracyano naphthoquinodimethane (F6TCNNQ), is utilized to form a van der Waals interface with a WS2 monolayer chemical vapor deposition grown on sapphire, which is characterized with angle‐resolved photoelectron and UV‐visible absorption spectroscopy. The interface formed by F6TCNNQ and the as‐grown WS2 monolayer (ML‐WS2) shows no sign of strong interaction or charge transfer. In contrast, defects formed by annealing of ML‐WS2 at 1000 K (d‐ML‐WS2) induce strong n‐type doping of the TMDC. Subsequent F6TCNNQ adsorption on d‐ML‐WS2 is then accompanied by pronounced charge transfer resulting in the formation of interface F6TCNNQ anions and an interface optical transition at 1.5 eV, possibly attributed to an interlayer excitonic state. It is shown in the results that the presence of defects within TMDC monolayers can substantially modify not only the TMDC electronic properties, but also the ground and excited states of their interface with organic molecular dopants. This demonstrates an additional degree of freedom for designing tailored (opto‐)electronic properties based on the combination of TMDCs and molecular semiconductors. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition metal dichalcogenide (TMDC) monolayers exhibit unique physical properties, such as self-terminating surfaces, a direct bandgap, and near-unity photoluminescence (PL) quantum yield (QY), which make them attractive for electronic and optoelectronic applications. Surface charge transfer has been widely used as a technique to control the concentration of free charge in 2D semiconductors, but its estimation and the impact on the optoelectronic properties of the material remain a challenge. In this work, we investigate the optical properties of a WS2 monolayer under three different doping approaches: benzyl viologen (BV), potassium (K), and electrostatic doping. Owing to the excitonic nature of 2D TMDC monolayers, the PL of the doped WS2 monolayer exhibits redshift and a decrease in intensity, which is evidenced by the increase in trion population. The electron concentrations of 3.79×1013 cm−2, 6.21×1013 cm−2, and 3.12×1012 cm−2 were measured for WS2 monolayers doped with BV, K, and electrostatic doping, respectively. PL offers a direct and versatile approach to probe the doping effect, allowing for the measurement of carrier concentration in 2D monolayer semiconductors.

Structural defects vary the optoelectronic properties of monolayer transition metal dichalcogenides, leading to concerted efforts to control defect type and density via materials growth or postgrowth passivation. Here, we explore a simple chemical treatment that allows on-off switching of low-lying, defect-localized exciton states, leading to tunable emission properties. Using steady-state and ultrafast optical spectroscopy, supported by ab initio calculations, we show that passivation of sulfur vacancy defects, which act as exciton traps in monolayer MoS2 and WS2, allows for controllable and improved mobilities and an increase in photoluminescence up to 275-fold, more than twice the value achieved by other chemical treatments. Our findings suggest a route for simple and rational defect engineering strategies for tunable and switchable electronic and excitonic properties through passivation.

Synthesized micro‐ and nanotubes composed of transition metal dichalcogenides (TMDCs) such as MoS2 are promising for many applications in nanophotonics because they combine the abilities to emit strong exciton luminescence and to act as whispering gallery microcavities even at room temperature. In addition to tubes in the form of hollow cylinders, there is an insufficiently studied class of twisted tubes, the flattened cross‐section of which rotates along the tube axis. As shown by theoretical analysis, in such nanotubes the interaction of electromagnetic waves excited at the opposite sides of the cross‐section can cause splitting of the whispering gallery modes. By studying micro‐photoluminescence spectra measured along individual MoS2 tubes, it has been established that the splitting value, which controls the energies of the split modes, depends exponentially on the aspect ratio of the cross‐section, which varies in "breathing" tubes, while the relative intensity of the modes in a pair is determined by the angle of rotation of the cross‐section. These results open up the possibility of creating multifunctional tubular TMDC nanodevices that provide resonant amplification of self‐emitting light at adjustable frequencies. [ABSTRACT FROM AUTHOR]

Porous silicon (PSi) improves the performance of commonly used silicon solar cells due to its large surface-to-volume ratio and high light absorption capability. PSi increases light absorption and power conversion efficiency (PCE) compared to traditional silicon solar cells. Due to the unique optical properties of transition metal dichalcogenides (TMDCs), device performance improves when a TMDC layer is added to PSi-based photonic devices. However, only three studies in the literature have investigated TMDC/PSi structures so far. In this study, a Gr/ReS2/PSi/p-cSi solar cell structure is discussed. In the proposed structure, Gr, ReS2 and PSi are used as transparent conductive electrode, interlayer and absorber, respectively. The effects of thicknesses, NC and NV, and doping concentrations of the graphene, ReS2 and PSi layers are examined and the layers are optimized. JSC, VOC, FF and PCE values of the optimized device are calculated as 32.83 mA/cm2, 0.88 V, 80.72% and 23.35%, respectively. In addition, 84.5% external quantum efficiency (EQE) at 550 nm and 0.467 A/W R at 790 nm are obtained. The proposed device demonstrates higher efficiency and VOC and FF values than the studies in the literature are obtained with the proposed structure. In addition, the reflectance of PSi and ReS2/PSi layers on a silicon (Si) substrate are calculated, and it is observed that these layers decrease reflectance due to their small refractive index. To the best of our knowledge, there is no study in the literature using ReS2 as an interlayer material. It is expected that the obtained results will be of benefit for future experimental and theoretical solar cell studies containing ReS2 layers. [ABSTRACT FROM AUTHOR]

Abstract In situ reflective high-energy electron diffraction (RHEED) is widely used to monitor the surface crystalline state during thin-film growth by molecular beam epitaxy (MBE) and pulsed laser deposition. With the recent development of machine learning (ML), ML-assisted analysis of RHEED videos aids in interpreting the complete RHEED data of oxide thin films. The quantitative analysis of RHEED data allows us to characterize and categorize the growth modes step by step, and extract hidden knowledge of the epitaxial film growth process. In this study, we employed the ML-assisted RHEED analysis method to investigate the growth of 2D thin films of transition metal dichalcogenides (ReSe2) on graphene substrates by MBE. Principal component analysis (PCA) and K-means clustering were used to separate statistically important patterns and visualize the trend of pattern evolution without any notable loss of information. Using the modified PCA, we could monitor the diffraction intensity of solely the ReSe2 layers by filtering out the substrate contribution. These findings demonstrate that ML analysis can be successfully employed to examine and understand the film-growth dynamics of 2D materials. Further, the ML-based method can pave the way for the development of advanced real-time monitoring and autonomous material synthesis techniques. Graphical Abstract

Two-dimensional (2D) monolayer pristine MoS 2 transition metal dichalcogenide (TMDC) is the most investigated material due to its potential applications as a non-precious electrocatalyst for the hydrogen evolution reaction (HER). However, the active edge sites created by sulfur non-stoichiometry and a defect-engineering by selective doping play a vital role in activating inert basal planes and enhancing the HER activity. Herein we report the synthesis of highly disordered Mn-doped 2D-MoS 2 nanospheres by a simple hydrothermal route under a non-equilibrium growth condition. Excess sulfur content in the precursor and electron-rich atmosphere created by Mn-doping results in an increased domain-based defects in the lattice that enhances the number of exposed edge sites, and also exposing more catalytically active high-index planes. Thereby improving its physicochemical properties. The developed electrode shows a low overpotential of 186 mV at a current density of 10 mA/cm2 and a low Tafel slope of 79.9mV/dec in acidic electrolytes. In addition, Density Functional Theory based calculation shows that Mn-doping in non-stoichiometric MoS 2 enhances the electronic properties and its role in facilitating hydrogen adsorption and desorption processes with free energy close to that of benchmark Pt is established. • Mn-doped MoS 2 nanosheets grown under a non-equilibrium hydrothermal process. • Nanosheets of MoS 2 were highly defect rich due to excess sulfur. • Mn-doping causes two order increase in the electrical conductivity of the catalyst. • The catalyst shows remarkably high hydrogen turnover rate of 1.45 s−1 at 0.2V. • DFT calculation shows a 10% substitutional doping by Mn would create thermodynamic condition similar to Pt. [ABSTRACT FROM AUTHOR]

Remote epitaxy, which was discovered and reported in 2017, has seen a surge of interest in recent years. Although the technology seemed to be difficult to reproduce by other labs at first, remote epitaxy has come a long way and many groups are able to consistently reproduce the results with a wide range of material systems including III-V, III-N, wide band-gap semiconductors, complex-oxides, and even elementary semiconductors such as Ge. As with any nascent technology, there are critical parameters which must be carefully studied and understood to allow wide-spread adoption of the new technology. For remote epitaxy, the critical parameters are the (1) quality of two-dimensional (2D) materials, (2) transfer or growth of 2D materials on the substrate, (3) epitaxial growth method and condition. In this review, we will give an in-depth overview of the different types of 2D materials used for remote epitaxy reported thus far, and the importance of the growth and transfer method used for the 2D materials. Then, we will introduce the various growth methods for remote epitaxy and highlight the important points in growth condition for each growth method that enables successful epitaxial growth on 2D-coated single-crystalline substrates. We hope this review will give a focused overview of the 2D-material and substrate interaction at the sample preparation stage for remote epitaxy and during growth, which have not been covered in any other review to date. [ABSTRACT FROM AUTHOR]

Multilayered van der Waals heterostructures based on transition metal dichalcogenides are suitable platforms on which to study interlayer (dipolar) excitons, in which electrons and holes are localized in different layers. Interestingly, these excitonic complexes exhibit pronounced valley Zeeman signatures, but how their spin-valley physics can be further altered due to external parameters—such as electric field and interlayer separation—remains largely unexplored. Here, we perform a systematic analysis of the spin-valley physics in MoSe 2 /WSe 2 heterobilayers under the influence of an external electric field and changes of the interlayer separation. In particular, we analyze the spin ( S z ) and orbital ( L z ) degrees of freedom, and the symmetry properties of the relevant band edges (at K, Q, and Γ points) of high-symmetry stackings at 0° (R-type) and 60° (H-type) angles—the important building blocks present in moiré or atomically reconstructed structures. We reveal distinct hybridization signatures on the spin and the orbital degrees of freedom of low-energy bands, due to the wave function mixing between the layers, which are stacking-dependent, and can be further modified by electric field and interlayer distance variation. We find that H-type stackings favor large changes in the g-factors as a function of the electric field, e.g., from − 5 to 3 in the valence bands of the H h h stacking, because of the opposite orientation of S z and L z of the individual monolayers. For the low-energy dipolar excitons (direct and indirect in k-space), we quantify the electric dipole moments and polarizabilities, reflecting the layer delocalization of the constituent bands. Furthermore, our results show that direct dipolar excitons carry a robust valley Zeeman effect nearly independent of the electric field, but tunable by the interlayer distance, which can be rendered experimentally accessible via applied external pressure. For the momentum-indirect dipolar excitons, our symmetry analysis indicates that phonon-mediated optical processes can easily take place. In particular, for the indirect excitons with conduction bands at the Q point for H-type stackings, we find marked variations of the valley Zeeman (∼4) as a function of the electric field, which notably stands out from the other dipolar exciton species. Our analysis suggests that stronger signatures of the coupled spin-valley physics are favored in H-type stackings, which can be experimentally investigated in samples with twist angle close to 60°. In summary, our study provides fundamental microscopic insights into the spin-valley physics of van der Waals heterostructures, which are relevant to understanding the valley Zeeman splitting of dipolar excitonic complexes, and also intralayer excitons. [ABSTRACT FROM AUTHOR]

The quench for the unremitting energy demand can be gratified by finding various substitute renewable energy sources and consequently safekeeping of these energies by energy storage devices. A variety of transition metal dichalcogenide (TMDC) materials are being explored for the application of water splitting and supercapacitor among which MoWS2 has gained its spot with potential tunable properties. Herein, the synthesis of MoWS2 and its nanocomposite with Ti3C2Tx MXene sheets is carried out by a simplistic hydrothermal method involving two steps. The structural and morphological characteristics were investigated through several characterization tools like powder X‐ray diffraction (pXRD), field emission scanning electron microscopy (FESEM), Raman spectroscopy and X‐ray photoelectron spectroscopy (XPS). The MXene sheets act as a template for the growth of MoWS2 (MWS) nanosheets and could exhibit extraordinary supercapacitive and electrocatalytic activity. The highest specific capacitance achieved by the pseudocapacitive MoWS2@MXene (MWSM) was 259 F/g @0.2 A/g. Then the above‐mentioned negative electrode was again taken for asymmetric studies where CoSe2@CNT@rGO was preferred as a positive site electrode and the asymmetric device showed a specific energy of 14 Wh/kg at a specific power of 8 KW/kg with an excellent cycling stability and coulombic efficiency of 93% and 96% which was measured for 6000 cycles. The hydrogen evolution reaction (HER) studies displayed that only 186 mV of overpotential was required to attain 10 mA/cm2 of current density. The electrocatalyst also achieved a small Tafel slope of 52 mV/dec along with exceptional stability upto 12 hours. High porosity, ample electrochemical active sites, rapid charge transfer kinetics and barrier‐free passage for ion transfer resulted in the enhanced electrochemical activity of MoWS2@MXene electrode/electrocatalyst. [ABSTRACT FROM AUTHOR]

In situ reflective high-energy electron diffraction (RHEED) is widely used to monitor the surface crystalline state during thin-film growth by molecular beam epitaxy (MBE) and pulsed laser deposition. With the recent development of machine learning (ML), ML-assisted analysis of RHEED videos aids in interpreting the complete RHEED data of oxide thin films. The quantitative analysis of RHEED data allows us to characterize and categorize the growth modes step by step, and extract hidden knowledge of the epitaxial film growth process. In this study, we employed the ML-assisted RHEED analysis method to investigate the growth of 2D thin films of transition metal dichalcogenides (ReSe2) on graphene substrates by MBE. Principal component analysis (PCA) and K-means clustering were used to separate statistically important patterns and visualize the trend of pattern evolution without any notable loss of information. Using the modified PCA, we could monitor the diffraction intensity of solely the ReSe2 layers by filtering out the substrate contribution. These findings demonstrate that ML analysis can be successfully employed to examine and understand the film-growth dynamics of 2D materials. Further, the ML-based method can pave the way for the development of advanced real-time monitoring and autonomous material synthesis techniques. [ABSTRACT FROM AUTHOR]

As down scaling of transistors continues, there is a growing interest in developing steep-slope transistors with reduced subthreshold slope (SS) below the Boltzmann limit. In this work, we successfully fabricated steep-slope MoS2 transistors by incorporating a graphene layer, inserted in the gate stack. For our comprehensive study, we have applied density functional theory to simulate and calculate the change of SS effected by different 2D quantum materials, including graphene, germanene and 2D topological insulators, inserted within the gate dielectric. This theoretical study showed that graphene/MoS2 devices had steep SS (27.2 mV/decade), validating our experimental approach (49.2 mV/decade). Furthermore, the simulations demonstrated very steep SS (8.6 mV/decade) in WTe2/MoS2 devices. We conclude that appropriate combination of various 2D quantum materials for the gate-channel stacks, leads to steep SS and is an effective method to extend the scaling of transistors with exceptional performance. [ABSTRACT FROM AUTHOR]

Gas sensors play a crucial role in fields extending from environmental to medical sciences. Modern FET‐based gas sensors have their own set of problems, so, in this work, an ultra‐small and highly sensitive TMDC material‐based gas sensor is proposed. Investigated nanowire‐based gas sensor has a radius and length of 4 nm and 20 nm respectively. Catalytic materials Molybdenum and Palladium are used as gate electrodes. MoS2, MoTe2 and WS2 are used as channel materials for the detection of Ammonia and to sense Hydrogen, MoS2 is used. The work function of catalytic materials changes due to the physical adsorption/chemisorption of gases. To include the quantum effects and to enhance the accuracy of results, along with Schrodinger‐Poisson equations, non‐equilibrium Green's function is used as a principle simulation model. Variations in characteristics of the sensor are explained on basis of transmission probability, density of states at source and drain electrode. For the detection of Ammonia, WS2 resulted in the highest ION/IOFF sensitivity of 1523 and MoS2 can detect Hydrogen at ION/IOFF sensitivity of 1137. The device investigated can be used in the future for the detection of the aforementioned gases. [ABSTRACT FROM AUTHOR]

The current need to accelerate the adoption of photovoltaic (PV) systems has increased the need to explore new nanomaterials that can harvest and convert solar energy into electricity. Transition metal dichalcogenides (TMDCs) are good candidates because of their tunable physical and chemical properties. CuCrS2 has shown good electrical and thermoelectrical properties; however, its optical and photoconductivity properties remain unexplored. In this study, we synthesized CuCrS2 nanosheets with average dimensions of 43.6 ± 6.7 nm in length and 25.6 ± 4.1 nm in width using a heat-up synthesis approach and fabricated films by the spray-coating method to probe their photoresponse. This method yielded CuCrS2 nanosheets with an optical bandgap of ~1.21 eV. The fabricated film had an average thickness of ~570 nm, exhibiting a net current conversion efficiency of ~11.3%. These results demonstrate the potential use of CuCrS2 as an absorber layer in solar cells. [ABSTRACT FROM AUTHOR]

Photonic topological insulators with robust boundary states can enable great applications for optical communication and quantum emission, such as unidirectional waveguide and single-mode laser. However, because of the diffraction limit of light, the physical insight of topological resonance remains unexplored in detail, like the dark line that exists with the crystalline symmetry-protected topological edge state. Here, we experimentally observe the dark line of the Z2 photonic topological insulator in the visible range by photoluminescence and specify its location by cathodoluminescence characterization, and elucidate its mechanism with the p-d orbital electromagnetic field distribution which calculated by numerical simulation. Our investigation provides a deeper understanding of Z2 topological edge states and may have great significance to the design of future on-chip topological devices.

Van der Waals epitaxy enables the integration of 2D transition metal dichalcogenides with other layered materials to form heterostructures with atomically sharp interfaces. However, the ability to fully utilize and understand these materials using surface science techniques such as angle resolved photoemission spectroscopy (ARPES) and scanning tunneling microscopy (STM) requires low defect, large area, epitaxial coverage with ultra-clean interfaces. We have developed a chemical vapor deposition van der Waals epitaxy growth process where the metal and chalcogen sources are separated such that growth times can be extended significantly to yield high coverage while minimizing surface contamination. We demonstrate the growth of high quality 2D WS2 over large areas on graphene. The as-grown vertical heterostructures are exceptionally clean as demonstrated by ARPES, STM and spatially resolved photoluminescence mapping. With these correlated techniques we are able to relate defect density to electronic band structure and, ultimately, optical properties. We find that our synthetic approach provides ultra-clean, low defect density (~1012 cm-2), ~10 μm large WS2 monolayer crystals, with an electronic band structure and valence band effective masses that perfectly match the theoretical prediction for pristine WS2.

Taking into account the novel layered structure and unusual electronic properties of MoS2 and WS2 on the side the lack of dangling bonds between these two components and donorâ€"acceptor linkage effects, growth of the MoS2/WS2 vertical heterojunction film on the amorphous SiO2/Si substrate have created high demand. In this study, we reported the continuous, scalable, and vertical MoS2/WS2 heterostructure film by using a sputtering without a transfer step. The WS2 film was continuously grown on MoS2 and eventually led to the formation of the MoS2/WS2 vertical heterojunction film. Dozens of FETs fabricated on MoS2/WS2 continuous heterojunction film were created on the same substrate in a single lithographic fabrication step, allowing them to be commercialized and not only used in research applications. RAMAN spectra proved the formation of the MoS2/WS2 heterostructure film. In XPS measurements, it was shown that a separate MoS2 and WS2 layer was grown instead of the alloy structure. The polarity behavior of the MoS2/WS2 heterostructure FET was found to be modulated with different drain voltages as p-type to ambipolar and finally n-type conductivity because of the transition of band structure and Schottky barrier heights at different drain voltages. Electron mobility (7.2 cm2 V.sâˆ'1) and on/off ratio (104â€"105) exhibited by the MoS2/WS2 heterostructure FETs displayed a more improved electrical performance than that of individual WS2, MoS2 devices. It was observed that the mobility value of MoS2/WS2 FET was approximately 514 times greater than WS2 FET and 800 times greater than MoS2 FET. Additionally, the MoS2/WS2 FET on/off ratio was larger than 2 order MoS2 FET and 1 order WS2 FET. The film of continuous vertical heterojunctions as in the MoS2/WS2 currents in the study would be a promising candidate for nanoelectronics fields. This work demonstrated the progress towards realizing carrier-type controlled high-performance MoS2/WS2 heterojunction-based FETs for future logic devices. [ABSTRACT FROM AUTHOR]

Significant studies haves been undertaken to improve the power conversion efficiency (PCE) of the Cu(In1−xGax)Se2 (CIGS) solar cell by varying the energy bandgap of the CIGS layer to match it with the solar spectrum and back surface field effect. In the past, a thin film CIGS solar cell with high PCE was reported with conventional CdS material as a buffer layer, which is a toxic material. In this paper, SCAPS-1D software is used to examine the performance of a single-junction solar cell as CIGS absorber with WS2 and WSSe Janus buffer materials to avoid the toxic effects of CdS material. Optimization of the CIGS energy bandgap is performed by stoichiometric variation of CIGS material composition. The impact of thickness and doping concentration of the CIGS absorber on the solar cell performance is further examined for device structures of n-ZnO:Al/n-WS2/p-CIGS and n-ZnO:Al/n-WSSe/p-CIGS. The study reveals that the WSSe Janus layer is a suitable material for fabrication of the buffer layer in CIGS solar cells. A maximum PCE of 25.81% is obtained for the CIGS solar cell with a WSSe buffer layer. Furthermore, the study analyzes effects of temperature, series/shunt resistance and work function of the metal contacts on the performance parameters of the solar cell. This simulation provides an approach to improve the efficiency of the CIGS solar device while decreasing the raw material consumption. [ABSTRACT FROM AUTHOR]

Atomically thin molybdenum disulfide (MoS2) is a promising channel material for next-generation thin-body field-effect transistors (FETs), which makes the development of methods allowing for its controllable synthesis over a large area an essential task. Currently, one of the cost-effective ways of its synthesis is the sulfurization of preliminary grown oxide- or metallic film. However, despite apparent progress in this field, the electronic quality of the obtained MoS2 is inferior to that of exfoliated samples, making the detailed investigation of the sulfurized films' properties of great interest. In this work, we synthesized continuous MoS2 films with a thickness of ≈2.2 nm via the sulfurization of an atomic-layer-deposited MoO3 layer. X-ray photoelectron spectroscopy, transmission electron microscopy, and Raman spectroscopy indicated the appropriate chemical composition and microcrystalline structure of the obtained MoS2 films. The semiconductor quality of the synthesized films was confirmed by the fabrication of a field-effect transistor (FET) with an Ion/Ioff ratio of ≈40, which was limited primarily by the high contact resistance. The Schottky barrier height at the Au/MoS2 interface was found to be ≈1.2 eV indicating the necessity of careful contact engineering. Due to its simplicity and cost-effectiveness, such a technique of MoS2 synthesis still appears to be highly attractive for its applications in next-generation microelectronics. Therefore, further research of the electronic properties of films obtained via this technique is required. [ABSTRACT FROM AUTHOR]

Reconfigurable waveguide components are promising building blocks for photonic neural networks and as an optical analogue to field-programmable gate arrays. By changing the effective index of the waveguide, reconfigurable waveguide components can achieve on-chip light routing and modulation. In this paper, we design and demonstrate an Sb2S3-reconfigurable InP membrane Machâ€"Zehnder interferometer (MZI) on a silicon substrate. Sb2S3, which has tunable refractive index and low absorption in the near-infrared spectrum, was patterned on the InP waveguide MZIs to make an optical switch in the telecoms conventional-band. By laser induced crystallisation of the Sb2S3, it was possible to control interference in the MZI and achieve 18 dB on/off switching at 1540 nm. Laser reamorphisation and reversible switching of the Sb2S3 layer resulted in damage to the waveguide structure. However, simulations show that transition metal di-chalcogenide two-dimensional crystal layers can act as efficient thermal barriers that prevent thermal damage to the waveguide during laser amorphisation. Therefore, combining Sb2S3 with InP waveguides seems to be a feasible approach to achieve low-loss reprogrammable waveguide components for on-chip photonics routing and neural networks. [ABSTRACT FROM AUTHOR]

This paper discusses the impact of the p-MoS2 transition metal dichalcogenide as an interfacial layer between the CZTS absorber and Mo back contact in the CZTS based solar cell. The study was performed using SCAPS-1D numerical simulation. The I–V characteristic demonstrated a higher slope than CZTS solar cells without considering the interfacial layer. The results verified that the p-MoS2 layer beneficially on the CZTS/Mo hetero-contact mediating an ohmic contact. Accordingly, the conversion efficiency improves from 12.14% to 16.71%. To evaluate the role of the p-MoS2 layer, various performance parameters such as open-circuit voltage (Voc), short circuit current (Jsc), fill factor FF, and efficiency η were explored versus thicknesses, bandgap energies, and the acceptor carrier concentration (NA). The results show that a thickness of the interfacial layer of less than 200 nm could cause deterioration of the overall cell performance, mainly due to created high barriers at the CZTS/p-MoS2 and p-MoS2/Mo interfaces, at low thicknesses, which impedes the drift of photogenerated holes. Additionally, increasing the NA above 1016 cm−3 improves the cell performance, owing to the favourable band alignment at the back contact. Values obtained for Voc and Jsc are 0.88 V and 25.5 mA/cm2, respectively. Moreover, the effect of series resistance Rs on CZTS solar cells was investigated. The efficiency decreases from 12.84% to 9.69% when the Rs correspondingly increases from 0 Ω to 5 Ω. [ABSTRACT FROM AUTHOR]

Enormous research and many noteworthy innovations have been done using Transition Metal Dichalcogenides (TMDCs) over the years. This class of layered semiconductor materials has found a strong foothold in the realm of device making due to theirs many versatile properties. The tunable band gap, accompanied with remarkable photonic and electronic properties, are a few of the striking features of these materials. They follow the 'MX2' type of arrangement with van der Waals forces holding the interlayers, where M (Mo, Nb, Re, Hf etc.) symbolizes a transition metal and X (Se, S or Te, etc.) is a chalcogen atom. Among the family, cobalt is used as a dopant to perk up the properties of many compounds. The focus of the work is to grow cobalt diselenide (CoSe2) by Direct Vapor Transport (DVT) method using a custom made dualzone furnace. XRD, HRTEM-SAED, SEM-EDX and UV-VIS-NIR spectroscopy are utilized to identify their structural, morphological and optical properties. XRD and SAED results confirm the polycrystalline nature of the sample prepared; also, the results are consistent with previously reported works. SEM and HRTEM depict the surface morphology and layered structure of the prepared sample. Also, EDX confirms the stoichiometry, purity and homogeneity of the prepared sample. The direct and indirect band gaps obtained using UV-VIS-NIR spectroscopy are 3.303 eV and 3.046 eV, respectively. [ABSTRACT FROM AUTHOR]

van der Waals heterostructures have emerged as an ideal platform for creating engineered artificial electronic states. While vertical heterostructures have been extensively studied, realizing high-quality lateral heterostructures with atomically sharp interfaces remains a major experimental challenge. Here, we advance a one-pot two-step molecular beam lateral epitaxy approach and successfully synthesize atomically well-defined 1T-VSe 2 ─1H-NbSe 2 lateral heterostructures. We demonstrate the formation of defect-free lateral heterostructures and characterize their electronic structure by using scanning tunneling microscopy and spectroscopy together with density functional theory calculations. We find additional electronic states at the 1D interface as well as signatures of Kondo resonances in a side-coupled geometry. Our experiments explored the full potential of lateral heterostructures for realizing exotic electronic states in low-dimensional systems for further studies of artificial designer quantum materials.

Transition metal dichalcogenide heterostructures have garnered strong interest for their robust excitonic properties, mixed light-matter states such as exciton-polaritons, and tailored properties, vital for advanced device engineering. Two-dimensional heterostructures inherit their physics from monolayers with the addition of interlayer processes that have been particularly emphasized for their electronic and optical properties. Here, we demonstrate the interlayer coupling of the MoSe 2 phonons to WSe 2 excitons in a WSe 2 /MoSe 2 heterostructure using resonant Raman scattering. The WSe 2 monolayer induces an interlayer resonance in the Raman cross-section of the MoSe 2 A 1g phonons. Frozen-phonon calculations within density functional theory reveal a strong deformation-potential coupling between the A 1g MoSe 2 phonon and the electronic states of the close-by WSe 2 layer approaching 20% of the intralayer coupling to the MoSe 2 electrons. Understanding the vibrational properties of van der Waals heterostructures requires going beyond the sum of their constituents and considering cross-material coupling.

Two-dimensional (2D) magnetic semiconductors offer an intriguing platform for investigating magneto-optoelectronic properties and hold immense potential in developing prospective devices when they are combined with valley electronic materials like 2D transition-metal dichalcogenides. Herein, we report various magneto-optoelectronic response features of the vertical hBN-FLG-CrI 3 -WSe 2 -FLG-hBN van der Waals heterostructure. Through a sensible layout and exquisite manipulation, an hBN-FLG-CrI 3 -FLG-hBN heterostructure was also fabricated on identical CrI 3 and FLGs for better comparison. Our results show that the WSe 2 -CrI 3 heterostructure, acting as a p - n heterojunction, has advantageous capability in light detection, especially in self-powered light helicity detecting. In the WSe 2 -CrI 3 heterojunction, the absolute value of photocurrent I PH exhibits obvious asymmetry with respect to the bias V , with the I PH of reversely biased WSe 2 -CrI 3 p-n heterojunction being larger. When the CrI 3 is fully spin-polarized under a 3 T magnetic field, the reversely biased WSe 2 -CrI 3 heterojunction exhibits advantageous capability in light helicity detecting. Both the short-circuit currents I SC and I PH show one-cycle fluctuation behaviors when the quarter-wave plate rotates 180°, and the corresponding photoresponsivity helicities can be as high as 18.0% and 20.1%, respectively. We attribute the spin-enhanced photovoltaic effect in the WSe 2 -CrI 3 heterojunction and its contribution to circularly polarized light detection to the coordination function of the spin-filter CrI 3 , the valley electronic monolayer WSe 2 , and the spin-dependent charge transfer between them. Our work helps us understand the interplay between the magnetic and optoelectronic properties of WSe 2 -CrI 3 heterojunctions and promotes the developing progress of prospective 2D spin optoelectronic devices.

Transition metal dichalcogenides (TMDCs) are ideal candidates to explore the manifestation of spin-valley physics under external stimuli. In this study, we investigate the influence of strain on the spin and orbital angular momenta, effective g -factors, and Berry curvatures of several monolayer TMDCs (Mo and W based) using a full ab initio approach. At the K -valleys, we find a surprising decrease of the conduction band spin expectation value for compressive strain, consequently increasing the dipole strength of the dark exciton by more than one order of magnitude (for ∼ 1 % â€" 2 % strain variation). We also predict the behavior of direct excitons g -factors under strain: tensile (compressive) strain increases (decreases) the absolute value of g -factors. Strain variations of ∼1% modify the bright (A and B) excitons g -factors by ∼0.3 (0.2) for W (Mo) based compounds and the dark exciton g -factors by ∼0.5 (0.3) for W (Mo) compounds. Our predictions could be directly visualized in magneto-optical experiments in strained samples at low temperature. Additionally, our calculations strongly suggest that strain effects are one of the possible causes of g -factor fluctuations observed experimentally. By comparing the different TMDC compounds, we reveal the role of spinâ€"orbit coupling (SOC): the stronger the SOC, the more sensitive are the spin-valley features under applied strain. Consequently, monolayer WSe2 is a formidable candidate to explore the role of strain on the spin-valley physics. We complete our analysis by considering the side valleys, Î" and Q points, and by investigating the influence of strain in the Berry curvature. In the broader context of valley- and strain-tronics, our study provides fundamental microscopic insights into the role of strain in the spin-valley physics of TMDCs, which are relevant to interpret experimental data in monolayer TMDCs as well as TMDC-based van der Waals heterostructures. [ABSTRACT FROM AUTHOR]

In this work, we investigate the performance of CIGS-based thin-film solar cells employing the SCAPS-1D simulation package. The paper is mainly devoted to the development of the ZrSxSe2−x (where 0 ≤ x ≤ 2) transition metal dichalcogenide (TMDC) as a Cd-free, nontoxic, and abundant buffer layer, the first of its kind. In the first step, we have evaluated the impact of the p-MoSe2 interfacial layer between the GIGS absorber and Mo back contact. The J–V characteristic showed a higher slope, revealing that the p-MoSe2 layer at the CIGS/Mo interfaces beneficially on the CIGS/Mo hetero-contact, mediating the quasi-ohmic contact rather than the Schottky type. For the optimized solar cell using the ZrSxSe2−x as a buffer layer, the photovoltaic parameters, such as the short-circuit current density, open-circuit voltage, Fill Factor, and efficiency, were investigated versus the thickness, carrier concentration, and bandgap values. The results reveal an optimum efficiency of ~ 25.5% at a bandgap of 1.3 eV, corresponding to ZrS0.8Se1.2 (i.e., x = 0.8) and 180 nm thicknesses, at a high carrier concentration of 1 × 1018 cm−3. Furthermore, the solar cell performance is assessed with the increment of the operating temperature from 275 to 475 K. The observed decrease in the Voc is ascribed to the rise in the reverse saturation current associated with the higher temperatures. The study concludes an excellent potential for fabricating high-performance CIGS thin solar cells using a Cd-free nontoxic buffer layer. [ABSTRACT FROM AUTHOR]

The transition-metal dichalcogenide (TMDC) in the family of MX 2 ( M = Mo , W ; X = S , Se ) and the graphene (Gr) monolayer are an atomically thin semiconductor and a semimetal, respectively. The monolayer MX 2 has been discovered as a new class of semiconductors for electronics and optoelectronics applications. Because of the hexagonal lattice structure of both materials, MX 2 and Gr are often combined with each other to generate van der Waals heterostructures. Here, the MX 2 / Gr heterostructures are investigated theoretically based on density functional theory (DFT). The electronic structure and the optical properties of four different MX 2 / Gr heterostructures are computed. We systematically compare these MX 2 / Gr heterostructures for their complex permittivity, absorption coefficient, reflectivity and refractive index. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenide (TDMCs) placed on a 3D semiconductor substrate haveleads to significant advances in the electronic industry with new opportunities based on 2D/3D heterojunction based diverse devices without any restrictions, such as lattice compatibility. In this study, magnetron sputtering technique was used to grow layered tungsten disulfide (WS2) thin films onto p-Si and thus WS2/p-Si heterojunctions were created. The structural and chemical parameters of this sputtered WS2 films were investigated using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Electrical characterization of WS2/p-Si heterojunction was also obtained to investigate Log (I)-V and linear I-V characteristics. A typical diode like I-V behavior was observed with a five-ordered rectifying ratio. It was observed that the heterojunction has a barrier height of 0.48 eV, the leakage current at -0.2 V is 2.25×10-6 A and the ideality factor is 5.7. This work show that single step magnetron sputtering WS2/p-Si heterojunction has great importance for heterojunction based future nanoelectronic devices.

A quantum system implanted with monolayer transition metal dichalcogenide (TMDC) is proposed as a valley filter based on a ballistic point contact with zigzag edges. A quantum point contact (QPC) structure is formed in the middle of scattering region and the geometrical size of the QPC is varied by electrostatic gate potentials. The energy band structures and electronic transport properties are investigated using a two-bands k ⋅ p Hamiltonian by using parameters from the density functional theory (DFT) calculations. The magnetic proximity effect from an Eu-terminated ferromagnetic substrate (EuS) generates a giant valley splitting in the energy of the monolayer WS 2 nanoribbon. The conductance is limited by reducing the width and by increasing the length of the QPC because conductance is strongly related to the number of transmission channels and the amounts of back scatterings at the QPC. The polarity of valley current can be manipulated by applying a local gate potential in the QPC region, where the manipulated polarity is limited to well defined K ′ polarization only. The lateral hetero materials on both sides of the QPC or lateral hetero ferromagnetic substrate is necessary to have desired valley and spin polarities of current by manipulating the local gate potential. The experimental realization of this quantum system will make it possible to control the valley degree of freedom in addition to controlling charge and spin degree of freedom of carriers in future electronic devices. [Display omitted] • The magnetic proximity effects of the substrate can break the spin and valley degeneracy of the system. • Using the two-band k ⋅ p Hamiltonian approximation, the band structures near the K and K' valleys are obtained. • Eu-terminated substrate can provide exchange interactions of 400 T B-field in the system. • Valley filtering device is designed as a bowtie-shaped system with a local gate in the center. • A heterojunction channel is required to have selective valley polarization. [ABSTRACT FROM AUTHOR]

Multilayered van der Waals heterostructures based on transition metal dichalcogenides are suitable platforms on which to study interlayer (dipolar) excitons, in which electrons and holes are localized in different layers. Interestingly, these excitonic complexes exhibit pronounced valley Zeeman signatures, but how their spin-valley physics can be further altered due to external parameters—such as electric field and interlayer separation—remains largely unexplored. Here, we perform a systematic analysis of the spin-valley physics in MoSe2/WSe2 heterobilayers under the influence of an external electric field and changes of the interlayer separation. In particular, we analyze the spin (Sz) and orbital (Lz) degrees of freedom, and the symmetry properties of the relevant band edges (at K, Q, and Γ points) of high-symmetry stackings at 0° (R-type) and 60° (H-type) angles—the important building blocks present in moiré or atomically reconstructed structures. We reveal distinct hybridization signatures on the spin and the orbital degrees of freedom of low-energy bands, due to the wave function mixing between the layers, which are stacking-dependent, and can be further modified by electric field and interlayer distance variation. We find that H-type stackings favor large changes in the g-factors as a function of the electric field, e.g., from −5 to 3 in the valence bands of the Hhh stacking, because of the opposite orientation of Sz and Lz of the individual monolayers. For the low-energy dipolar excitons (direct and indirect in k-space), we quantify the electric dipole moments and polarizabilities, reflecting the layer delocalization of the constituent bands. Furthermore, our results show that direct dipolar excitons carry a robust valley Zeeman effect nearly independent of the electric field, but tunable by the interlayer distance, which can be rendered experimentally accessible via applied external pressure. For the momentum-indirect dipolar excitons, our symmetry analysis indicates that phonon-mediated optical processes can easily take place. In particular, for the indirect excitons with conduction bands at the Q point for H-type stackings, we find marked variations of the valley Zeeman (∼4) as a function of the electric field, which notably stands out from the other dipolar exciton species. Our analysis suggests that stronger signatures of the coupled spin-valley physics are favored in H-type stackings, which can be experimentally investigated in samples with twist angle close to 60°. In summary, our study provides fundamental microscopic insights into the spin-valley physics of van der Waals heterostructures, which are relevant to understanding the valley Zeeman splitting of dipolar excitonic complexes, and also intralayer excitons.

In this paper, we report on the device concepts for high-gain operation of a tungsten diselenide (WSe2) complementary metal-oxide-semiconductor (CMOS) inverter at a low power supply voltage (V dd ), which was realized by developing a doping technique and gate stack technology. A spin-coating with a fluoropolymer and poly(vinyl alcohol) (PVA) results in the doping of both electrons and holes to WSe2. A hybrid self-assembled monolayer/aluminum oxide (AlO x) gate dielectric is viable for achieving high gate capacitance and superior interfacial properties. By developing the doping technique and gate stack technology, we experimentally realized a high gain of 9 at V dd of 0.5 V in the WSe2 CMOS inverter. This study paves the way for the research and development of transition metal dichalcogenides-based devices and circuits. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have been widely used in photodetectors owing to their diverse advantages in device fabrication and manipulation, such as integration flexibility, availability of optical operation through an ultrabroad wavelength band, fulfilling of photonic demands at low cost, and applicability in photodetection with high-performance. Recently, transition metal dichalcogenides (TMDCs), black phosphorus (BP), III-V materials, heterostructure materials, and graphene have emerged at the forefront as intriguing basics for optoelectronic applications in the field of photodetection. The versatility of photonic systems composed of these materials enables their wide range of applications, including facilitation of chemical reactions, speeding-up of responses, and ultrasensitive light detection in the ultraviolet (UV), visible, mid-infrared (MIR), and far-infrared (FIR) ranges. This review provides an overview, evaluation, recent advancements as well as a description of the innovations of the past few years for state-of-the-art photodetectors based on two-dimensional materials in the wavelength range from UV to IR, and on the combinations of different two-dimensional crystals with other nanomaterials that are appealing for a variety of photonic applications. The device setup, materials synthesis, operating methods, and performance metrics for currently utilized photodetectors, along with device performance enhancement factors, are summarized.

Two-dimensional (2D) transition metal chalcogenides (TMDCs) and carbide have validated boundless prospective as multi-functional constituents for high performance energy storing and/or conversion devices. However, pure TMDCs exhibit poor performance for electrochemical applications due to low electrical conductivity, scarce electrochemically active edges and inadequate cycling stability. Therefore, this paper fabricated MXene/WSe 2 hybrids with strong interfacial interactions and conductivities using a one-step chemical reaction as electrodes for supercapacitors and hydrogen evolution. Fabricated supercapacitors achieved high specific capacitance = 840 F g−1 at 2 A g−1, with symmetric capacitance = 246 F g−1 at 2 A g−1 for MXene/WSe 2 hybrids. Hydrogen evolution achieved low overpotentials = 76 and 62 mV to drive 10 mA cm−2 current with small Tafel slopes = 78 and 84 mV.dec−1 in acid and base media, respectively. 2D and 2D hybrid WSe 2 nanoparticle composite embedded MXene scaffolds achieved excellent electron/ion intercalation owing to its distinctive 2D-layered structure, increasing interlayer spacing and retaining large electrode/electrolyte contact to enhance efficiency. Two-dimensional TMDCs/MXene composites were verified as potentially efficient electrode materials for energy storing and exchange uses. [ABSTRACT FROM AUTHOR]

A Density Functional Theory based simulation study on cubic crystal orientation dependent transition metal contact with monolayer MoS2/WS2 in reference to exchange energy, density of states and thermodynamic entropy measurements are studied. Exchange energy states the stability of the interfaces between MoS2/WS2 and transition metals. The density of states calculation reveals the transport dominance with respect to charge polarity (electron or hole) and magnitude of charge flow through the interface. Entropy gives an alternative view to analyse carrier-phonon scattering at the interface. Our calculations suggest that (100) and (111) orientated transition metals from 3d group like Sc, Ti, Cr, Co, and Ni, (110) orientated transition metals from 4d group like Tc, Pd, Zr, and Ag and from 5d group (100), (110) orientated elements like Ta, W, Os, Ir, Pt are better suited for elemental contact applications in MoS2 and WS2 channel-based CMOS logic FETs. [ABSTRACT FROM AUTHOR]

Heterostructures (HSs) formed by the transition-metal dichalcogenide materials have shown great promise in next-generation (opto)electronic applications. An artificially twisted HS allows us to manipulate the optical and electronic properties. In this work, we introduce the understanding of the energy transfer (ET) process governed by the dipolar interaction in a twisted molybdenum diselenide (MoSe 2 ) homobilayer without any charge-blocking interlayer. We fabricated an unconventional homobilayer (i.e., HS) with a large twist angle (∼57°) by combining the chemical vapor deposition (CVD) and mechanical exfoliation (Exf.) techniques to fully exploit the lattice parameter mismatch and indirect/direct (CVD/Exf.) bandgap nature. These effectively weaken the interlayer charge transfer and allow the ET to control the carrier recombination channels. Our experimental and theoretical results explain a massive HS photoluminescence enhancement due to an efficient ET process. This work shows that the electronically decoupled MoSe 2 homobilayer is coupled by the ET process, mimicking a "true" heterobilayer nature.

Using a computational approach based on the driven diffusion equation for dipolariton wave packets, we simulate the diffusive dynamics of dipolaritons in an optical microcavity embedded with a transition metal dichalcogenide (TMDC) heterogeneous bilayer encompassing a Ψ -shaped channel. By considering exciton-dipolaritons, which are a three-way superposition of direct excitons, indirect excitons and cavity photons, we are able to drive the dipolaritons in our system by the use of an electric voltage and investigate their diffusive properties. More precisely, we study the propagation of dipolaritons present in a MoSe2-WS2 heterostructure, where the dipolariton propagation is guided by a Ψ -shaped channel. We also consider the propagation of dipolaritons in the presence of a buffer in the Ψ -shaped channel and study resulting changes in efficiency. We introduce designs for optical routers at room-temperature as well as show that system parameters including driving forces of ≈ 2. 0 eV/mm and electric field angles of 6 0 ∘ optimize the dipolariton redistribution efficiencies in our channel guide. [ABSTRACT FROM AUTHOR]

Atomically thin molybdenum disulfide (MoS2) is a promising channel material for next-generation thin-body field-effect transistors (FETs), which makes the development of methods allowing for its controllable synthesis over a large area an essential task. Currently, one of the cost-effective ways of its synthesis is the sulfurization of preliminary grown oxide- or metallic film. However, despite apparent progress in this field, the electronic quality of the obtained MoS2 is inferior to that of exfoliated samples, making the detailed investigation of the sulfurized films’ properties of great interest. In this work, we synthesized continuous MoS2 films with a thickness of ≈2.2 nm via the sulfurization of an atomic-layer-deposited MoO3 layer. X-ray photoelectron spectroscopy, transmission electron microscopy, and Raman spectroscopy indicated the appropriate chemical composition and microcrystalline structure of the obtained MoS2 films. The semiconductor quality of the synthesized films was confirmed by the fabrication of a field-effect transistor (FET) with an Ion/Ioff ratio of ≈40, which was limited primarily by the high contact resistance. The Schottky barrier height at the Au/MoS2 interface was found to be ≈1.2 eV indicating the necessity of careful contact engineering. Due to its simplicity and cost-effectiveness, such a technique of MoS2 synthesis still appears to be highly attractive for its applications in next-generation microelectronics. Therefore, further research of the electronic properties of films obtained via this technique is required.