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Two-dimensional (2D) materials have garnered momentous consideration owing to their inimitable structural and physiochemical properties, enabling diverse technological applications. Tungsten disulfide (WS2), a prominent transition metal dichalcogenide, exhibits exceptional characteristics such as a tunable bandgap, large surface area, and strong biocompatibility, making it highly suitable for biosensing applications. This review explores various WS2 synthesis techniques, including mechanical exfoliation, sonication, and chemical exfoliation, highlighting their impact on nanosheet quality and scalability. Furthermore, it examines WS2’s role in biosensing, particularly in cancer biomarker detection, DNA/RNA sensing, enzyme activity monitoring, and pathogen identification. Despite its promising applications, challenges such as oxidation, long-term stability, and large-scale synthesis persist. Future advancements in hybrid nanostructures, functionalization techniques, and AI-assisted biosensing are expected to enhance WS2’s reliability and expand its practical deployment. By addressing these challenges, WS2-based technologies can drive significant innovations in diagnostics and environmental monitoring.

An ionic liquid-polyaniline/tungsten disulfide (IL-PANI/WS 2 ) composite was synthesized in 1-butyl-3-methylimidazole tetrafluoroborate (LB104) aqueous solution by in-situ polymerization and characterized by Fourier transform infrared spectroscopy. A current-carrying friction and wear tester was used to study the tribological properties of steel—steel and copper—copper friction pairs lubricated by an IL-PANI/WS 2 lithium complex grease (LCG). After the experiment, scanning electron microscope was used to observe the surface morphology of the wear scar on the steel and copper plates, and X-ray photoelectron spectrometer was used to analyze the elemental composition of the wear scar surface. The results show that compared with greases containing IL-PANI and WS 2 , greases containing IL-PANI/WS 2 exhibit better antiwear performance when lubricating steel—steel friction pairs and better tribological performance and electrical conductivity when lubricating copper—copper friction pairs. Therefore, it can be concluded that WS 2 and IL-PANI have a synergistic effect.

This study investigates the chemical and structural modifications of vertically aligned tungsten disulfide–tungsten trioxide (WS2-WO3) nanosheets decorated with silver nanoparticles (Ag(NPs)) under nitrogen plasma conditions. The synthesized vertically aligned WS2-WO3 nanosheets were functionalized through direct-current (DC) magnetron sputtering, forming silver-decorated samples. Structural changes, as well as the size and distribution of Ag(NPs), were characterized using scanning electron microscopy (SEM). Chemical state analysis was conducted via X-ray photoelectron spectroscopy (XPS), while Raman spectroscopy was employed to investigate vibrational modes. The findings confirmed the successful decoration of Ag(NPs) and identified unexpected compound transformations that were dependent on the duration of functionalization. The synthesized and functionalized samples were evaluated for their sensing capabilities towards Rhodamine B (RhB) through surface-enhanced resonance Raman scattering (SERRS). This study discusses the impact of substrate morphology and the shape and size of nanoparticles on the enhancement of SERRS mechanisms, achieving an enhancement factor (EF) of approximately 1.6 × 106 and a limit of detection (LOD) of 10−9 M.

In this paper, we propose an ultrascaled WS2 field-effect transistor equipped with a Pd/Pt sensitive gate for high-performance and low-power hydrogen gas sensing applications. The proposed nanosensor is simulated by self-consistently solving a quantum transport equation with electrostatics at the ballistic limit. The gas sensing principle is based on the gas-induced change in the metal gate work function. The hydrogen gas nanosensor leverages the high sensitivity of two-dimensional WS2 to its sur-rounding electrostatic environment. The computational investigation encompasses the nanosensor’s behavior in terms of potential profile, charge density, current spectrum, local density of states (LDOS), transfer characteristics, and sensitivity. Additionally, the downscaling-sensitivity trade-off is analyzed by considering the impact of drain-to-source voltage and the electrostatics parameters on subthreshold performance. The simulation results indicate that the downscaling-sensitivity trade-off can be optimized through enhancements in electrostatics, such as utilizing high-k dielectrics and reducing oxide thickness, as well as applying a low drain-to-source voltage, which also contributes to improved energy efficiency. The proposed nanodevice meets the prerequisites for cutting-edge gas nanosensors, offering high sensing performance, improved scaling capability, low power consumption, and complementary metal–oxide–semiconductor compatibility, making it a compelling candidate for the next generation of ultrascaled FET-based gas nanosensors.

Researchers are developing innovative electrode materials with high energy and power densities worldwide for effectual energy storage systems. Transition metal dichalcogenides (TMDs) are arranged in two dimensions (2D) and have shown great promise as materials for photoelectrochemical activity and supercapacitor batteries. This study reports on the fabrication of WS2@NiCoS and WS2@NiCoS@ZnS hybrid nano-architectures through a simple hydrothermal approach. Because of the strong interfacial contact between the two materials, the resultant hierarchical hybrids have tunable porosity nanopetal decorated morphologies, rich exposed active edge sites, and high intrinsic activity. The specific capacities of the hybrid supercapacitors built using WS2@NiCoS and WS2@NiCoS@ZnS electrodes are 784.38 C g−1 and 1211.58 C g−1 or 2019.3 F g−1, respectively, when performed at 2 A g−1 using a three-electrode setup. Furthermore, an asymmetric device (WS2@NiCoS@ZnS//AC) shows a high specific capacity of 190.5 C g−1, an energy density of 49.47 Wh kg−1, and a power density of 1212.30 W kg−1. Regarding the photoelectrochemical activity, the WS2@NiCoS@ZnS catalyst exhibits noteworthy characteristics. Our findings pave the way for further in-depth research into the use of composite materials doped with WS2 as systematic energy-generating devices of the future.

A “turn on” time-resolved fluorometric aptasensor is described for the simultaneous detection of zearalenone (ZEN), trichothecenes A (T-2), and aflatoxin B 1 (AFB 1 ). Multicolor-emissive nanoparticles doped with lanthanide ions (Dy 3+ , Tb 3+ , Eu 3+ ) were functionalized with respective aptamers and applied as a bioprobe, and tungsten disulfide (WS 2 ) nanosheets are used as a quencher of time-resolved fluorescence. The assay exploits the quenching efficiency of WS 2 and the interactions between WS 2 and the respective DNA aptamers. The simultaneous recognition of the three mycotoxins can be performed in a single solution. In the absence of targets, WS 2 is easily adsorbed by the mixed bioprobes via van der Waals forces between nucleobases and the WS 2 basal plane. This brings the bioprobe and WS 2 into close proximity and results in quenched fluorescence. In the presence of targets, the fluorescence of the bioprobes is restored because the analytes react with DNA probe and modify their molecular conformation to weaken the interaction between the DNAs and WS 2 . Under the optimum conditions and at an excitation wavelength of 273 nm, the time-resolved fluorescence intensities (peaking at 488, 544 and 618 nm and corresponding to emissions of Dy 3+ , Tb 3+ and Eu 3+ ) were used to quantify ZEN, T-2 and AFB 1 , respectively, with detection limits of 0.51, 0.33 and 0.40 pg mL −1 and a linear range from 0.001 to 100 ng mL −1 . The three mycotoxins can be detected simultaneously without mutual interference. The assay was applied to the quantification of ZEN, T-2 and AFB 1 in (spiked) maize samples. This homogeneous aptamer based assay can be performed within 1 h. Conceivably, it can become an alternative to other heterogeneous methods such as the respective enzyme-linked immunosorbent assays. Graphical abstract Schematic presentation of an aptasensor for simultaneous detection of zearalenone, trichothecenes A and aflatoxin B 1 using aptamer modified time-resolved fluorescence nanoparticles as signalling probes and tungsten disulfide as the quencher. This assay shows lower detection limit and requires no washing steps.

Water is a vital ingredient for life, but its quality is constantly deteriorating due to textile effluent carrying harmful dyes. Photodegradation is a highly effective process for breaking down dye using solar spectrum. In the current work, hydrothermal approach was used to designed pure tungsten disulfide and doped tungsten disulfide with differnet concentration (5, 10, and 15%) for photocatalytic degradation of methylene voilet. Different instrumental analyses were conducted to measure the physichemical and optical properties of the fabricated pure and doped materials. The photocatalytic behavior of the WS2, 5% doped WS2, 10% doped WS2 and 15% doped WS2 was noted after 0, 15, 30, 45, 60, and 75 min under sunlight. The removal of methyl violet (MV) by using pristine WS2, 5% doped WS2, 10% doped WS2 was about 51, 70, and 80%, respectively. The maximum degradation of methylene violet was given by 15% doped WS2 about 90% after 75 min under sunlight. The 15% doping of the Sm reduced the band gap that can effectively absorb the greater extent of the solar spectrum and degrade the methyl violet dye. The fabricated optimized doped photocatalyst can also be employed in other application such as batteries, drug delivery, and water splitting.

Two-dimensional (2D) materials, such as tungsten disulfide (WS2), have attracted considerable attention for their potential in gas sensing applications, primarily due to their distinctive electrical properties and layer-dependent characteristics. This research explores the impact of the number of WS2 layers on the ability to detect gases by examining the layer-dependent sensing performance of WS2-based gas sensors. We fabricated gas sensors based on WS2 in both monolayer and multilayer configurations and methodically evaluated their response to various gases, including NO2, CO, NH3, and CH4 at room temperature and 50 degrees Celsius. In contrast to the monolayer counterpart, the multilayer WS2 sensor exhibits enhanced gas sensing performance at higher temperatures. Furthermore, a comprehensive gas monitoring system was constructed employing these WS2-based sensors, integrated with additional electronic components. To facilitate user access to data and receive alerts, sensor data were transmitted to a cloud-based platform for processing and storage. This investigation not only advances our understanding of 2D WS2-based gas sensors but also underscores the importance of layer engineering in tailoring their sensing capabilities for diverse applications. Additionally, the development of a gas monitoring system employing 2D WS2 within this study holds significant promise for future implementation in intelligent, efficient, and cost-effective sensor technologies.

Substrates provide the necessary support for scientific explorations of numerous promising features and exciting potential applications in two-dimensional (2D) transition metal dichalcogenides (TMDs). To utilize substrate engineering to alter the properties of 2D TMDs and avoid introducing unwanted adverse effects, various experimental techniques, such as high-frequency Raman spectroscopy, have been used to understand the interactions between 2D TMDs and substrates. However, sample-substrate interaction in 2D TMDs is not yet fully understood due to the lack of systematic studies by techniques that are sensitive to 2D TMD-substrate interaction. This work systematically investigates the interaction between tungsten disulfide (WS 2 ) monolayers and substrates by low-frequency Raman spectroscopy, which is very sensitive to WS 2 -substrate interaction. Strong coupling with substrates is clearly revealed in chemical vapor deposition (CVD)-grown monolayer WS 2 by its low-wavenumber interface mode. It is demonstrated that the enhanced sample-substrate interaction leads to tensile strain on monolayer WS 2 , which is induced during the cooling process of CVD growth and could be released for monolayer WS 2 sample after transfer or fabricated by an annealing-free method such as mechanical exfoliation. These results not only suggest the effectiveness of low-frequency Raman spectroscopy for probing sample-substrate interactions in 2D TMDs, but also provide guidance for the design of high-performance devices with the desired sample-substrate coupling strength based on 2D TMDs.

Transition metal dichalcogenide (TMDs) heterostructure, particularly the lateral heterostructure of two different TMDs, is gaining attention as ultrathin photonic devices based on the charge transfer (CT) excitons generated at the junction. However, the characteristics of the interface of the lateral heterostructure, determining the electronic band structure and alignment at the heterojunction region, have rarely been studied due to the limited spatial resolution of nondestructive analysis systems. In this study, we investigated the confined phonons resulting from the phonon-disorder scattering process involving multiple disorders at the lateral heterostructure interface of MoS –WS to prove the consequences of disorder-mediated deformation in the band structure. Moreover, we directly observed variations in the metal composition of the multi-disordered nanoscale alloy Mo , consisting of atomic vacancies, crystal edges, and distinct nanocrystallites. Our findings through tip-enhanced Raman spectroscopy (TERS) imply that a tens of nanometer area of continuous TMDs alloy forms the multi-disordered interface of the lateral heterostructure. The results of this study could present the way for the evaluation of the TMDs lateral heterostructure for excitonic applications.