Transition Metal Dichalcogenides Family Research Articles

General Synthesis Strategy of 2D Transition Metal Dichalcogenide Gradient Alloys for High‐Performance Optoelectronic Synapses

Abstract2D transition metal dichalcogenide (TMD) gradient alloys hold great promise for electronic and optoelectronic applications, benefiting from their structural and compositional diversity as well as potential multifunctionalities. However, critical challenges remain in the controlled synthesis and unexplored uses of 2D TMD gradient alloys compared to single‐composition 2D TMDs. Herein, a “Face‐to‐Face” general synthesis strategy, which enables large‐area, uniform, and highly reproducible preparation of multiple types of 2D TMD gradient alloys in a single configuration through precise control on precursor supply, and the spatial confinement effect is reported. The synthesized single‐layer Mo1‐xWxS2 gradient alloy features a graded energy band and an alloyed region with moderate intrinsic sulfur vacancies, which is beneficial to achieving the high photo‐synaptic response. Optoelectronic synaptic devices utilizing the unique properties of 2D gradient alloys demonstrate various neuromorphic behaviors, such as outstanding‐index 161% paired‐pulse facilitation, stimuli‐dependent transition from short‐term plasticity to long‐term plasticity, emulation of the brain‐like learning processes, and simulation of neuromorphic vision on artificial neural network for handwritten digit recognition with over 95.6% accuracy. The present general synthesis method of 2D gradient alloys and their great potential as high‐performance optoelectronic synapses may open new frontiers for the 2D TMD family.

The transition-metal-dichalcogenide family as a superconductor tuned by charge density wave strength

In metallic transition metal dichalcogenides (TMDs), which remain superconducting down to single-layer thickness, the critical temperature Tc decreases for Nb-based, and increases for Ta-based materials. This contradicting trend is puzzling, impeding the development of a unified theory. Here we study the thickness-evolution of superconducting tunneling spectra in TaS2 heterostructures. The upper critical field Hc2 is strongly enhanced towards the single-layer limit – following Hc2∝Tc2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${H}_{c2}\\propto {T}_{c}^{2}$$\\end{document}. The same ratio holds for the entire family of intrinsically metallic 2H-TMDs, covering 4 orders of magnitude in Hc2. Using Gor’kov’s theory, we calculate the suppression of Tc by the competing charge density wave (CDW) order, which affects the quasiparticle density of states and the resulting Tc and Hc2. The latter is found to be universally enhanced by two orders of magnitude. Our results substantiate CDW as the key determinant factor limiting Tc across the TMD family.

Mo0.5W0.5S2 as saturable absorber for passively mode-locked Tm:YAP laser

In recent years, 2 μm pulsed lasers have received extensive attention from researchers due to their wide applications in materials processing and medical fields. In this work, we reported preparing Mo0.5W0.5S2 saturable absorber (SA) via liquid phase exfoliation and successfully using this SA in Tm:YAP lasers to generate passively mode-locked (PML) pulses. An average output power of 0.87 W was achieved with the injected pump power of 20.38 W in the PML Tm:YAP laser, corresponding to a slope efficiency of 4.8%. Moreover, a pulse width of 686.4 ps at 85.9 MHz was acquired with a central output wavelength of 1935 nm from the laser, and the beam quality of M2 was measured to be 1.10 and 1.12 in the X and Y directions. The potential of Mo0.5W0.5S2 material in the transition metal dichalcogenides family for saturable absorption property in the 2 μm region was demonstrated by this work.

Nanoarchstructured MoS2-based strain sensor with exceptional gauge factor

Two-dimensional (2D) MoS2, part of the transition metal dichalcogenides family, has emerged as a promising candidate for wearable strain sensors owing to its unique attributes, including mechanical flexibility, low toxicity, tunable and high electrical properties. MoS2-based sensors exhibit higher gauge factors (∼760 for monocrystalline, ∼56.5 for polycrystalline) and a lower limit of detection than conventional metal sensors. We report an advanced strain sensor with ultra-high sensitivity to minute deformations, exploiting a three-dimensional nanostructured-2D MoS2 (3DN-MoS2) with an arch-like configuration. The nanoarchstructured MoS2-based strain sensor (NaM-SS) achieves exceptional gauge factors, exceeding 1500 for tensile strain, using 3DN-MoS2 sensing material in conjunction with a poly-dimethylsiloxane support. This piezo-resistive sensor, fabricated through an eco-friendly and straightforward process, exhibits remarkable gauge factors at three levels: 1500 (ε < 0.55 %), 13,500 (0.55 %< ε ≤ 0.75 %), and 37,000 (0.75 % < ε ≤ 1.2 %). The sensor’s limit of detection stands at a subtle tensile strain ε of 0.02 %. Furthermore, its feasibility is validated by its ability to monitor various human physical motions, including eye blinking, blood pulsation, and muscle activity. Our findings indicate significant potential for precision strain sensors in applications requiring ultra-high sensitivity, such as detecting subtle biomedical signals, meticulous machinery control, and structural health monitoring.

Deposition of ReS2 Thin Films Using Aerosol-Assisted Chemical Vapor Deposition

Transition metal dichalcogenides (TMDCs) have remarkable properties, which can make these materials as a source alternative to graphene. The new member of TMDCs family ReS2 has got interest because its unique property. Synthesis ReS2 still needs a high temperature to deposit; the high deposition temperature makes ReS2 materials highly cost to produce. In this work the rhenium carbamate complex ([Re2(μ-S)2(S2CNEt2)4]) which have a high thermal stability was used to synthesis ReS2 thin films by reducing the deposition temperature to 525 °C, 25 °C less from previous study. The produced thin films were deposited using Aerosol-Assisted Chemical Vapor Deposition (AA-CVD). Films have been characterized firstly by p-XRD which confirmed that ReS2 thin films were successfully prepared, then the morphology of thin film were investigated by SEM and the results showed morphology was smooth and uniformed.

Bottom-up Synthesis of Highly Chiral 1T Molybdenum Disulfide Nanosheets.

Chirality in inorganic nanostructures has recently stimulated the attention of many researchers, both to unravel fundamental questions on the origin of chirality in inorganic and hybrid materials, as well as to introduce novel promising properties that are originated by the symmetry breaking. MoS2 is one of the most investigated among the large family of layered transition metal dichalcogenides. In particular, the metastable metallic 1T-MoS2 phase is of large interest for potential applications. However, due to thermodynamic reasons, the synthesis of 1T-MoS2 phase is quite challenging. Herein, we present the first synthesis of chiral 1T-MoS2 phase which shows remarkably high chiroptical activity with a g-factor up to 0.01. Chiral 1T-MoS2 was produced using tartaric acid as a chiral ligand to induce symmetry breaking during the material's growth under hydrothermal conditions, leading to the formation of distorted hierarchical nanosheet assemblies exhibiting chiral morphology. Thorough optimization of the synthetic conditions was carried out to maximize chiroptical activity, which is strongly related to the nanostructures' morphology. Finally, the formation mechanism of the chiral 1T-MoS2 nanosheet assemblies was investigated, focusing on the role of molecular intermediates in the growth of the nanosheets and the transfer of chirality.

Enhanced Hydrogen Evolution Reaction Activity through Bimetallic Phosphide Integration in ReS2/Re2O7 Heterostructure

AbstractDeveloping a nonprecious and sustainable electrocatalyst in clean energy generation is quite noteworthy. Transition metal chalcogenides, oxides, and phosphides have emerged as promising candidates to substitute Pt‐based catalysts. In this study, we explore the catalytic potential of ReS2, a promising member of the transition metal dichalcogenides (TMD) family, for hydrogen evolution reactions (HER). The formation of rhenium oxide during the synthesis of ReS2 and further incorporation of a bimetallic phosphide NiCuP in a sequential hydrothermal synthesis reveals an excellent HER activity, as demonstrated by photoelectrochemical and electrochemical studies. Notably, the catalyst exhibits a significantly lower overpotential of −0.10 V (corresponding to −10 mA/cm2) and achieves a high current density of approx. −271 mA/cm2 at −0.79 V versus reversible hydrogen electrode (RHE) under light irradiation. The catalyst demonstrates high stability. These findings underscore the potential of NiCuP‐integrated ReS2/Re2O7 as a highly efficient and sustainable catalyst for HER.

Janus Doping of Sulfur into Platinum Diselenide Ribbons.

2D platinum diselenide (PtSe2), a novel member of the transition metal dichalcogenides (TMDCs) family, possesses many excellent properties, including a layer-dependent bandgap, high carrier mobility, and broadband response, making it promise for applications in technologies like field-effect transistors and room-temperature photodetectors. Doping represents an effective method to modify the electrical properties of 2D TMDCs and to bestow upon them additional functions. However, to date, little research has been conducted on the successful doping of 2D PtSe2 for modification. In this study, sulfur (S) powder is utilized during the chemical vapor deposition growth process of 2D PtSe2 ribbons and successfully integrated into the PtSe2 lattice through substitutional doping. The Au substrate significantly decreases the substitution energy of Se atoms in the lower layer of PtSe2, resulting in the formation of the Janus PtSSe structure. S-doped PtSe2 ribbons demonstrate significant symmetry breaking and enhanced electrical properties, showcasing a strong nonlinear optical response and certain synaptic plasticity, further simulating some neuromorphological processes. This study not only demonstrates a viable method for controllable doping and modification of 2D PtSe2 but also establishes a platform for exploring the characteristics of Janus TMDCs.

Nanotubes and other nanostructures of VS2, WS2, and MoS2: Structural effects on the hydrogen evolution reaction

Vanadium sulfide (VS2) is a layered transition metal dichalcogenide (TMD), comparable in crystal structure to the well-known MoS2 and WS2. Theoretical predictions attribute much potential to VS2, since it is metallic-like and has an active basal plane, essential for catalytic performance. However, it is much less studied than other members of the TMD family due to the difficulties in synthesizing specific structures with controlled properties. Here we present unique structures of VS2 nanotubes and conduct a comparative study with other well-known inorganic nanotubes and nanostructures of MoS2 and WS2. We evaluate the effect of the curvature and strain, the abundance of surface defects, and the availability of surface sites in various structures by electrochemical methods. We show that MoS2 has the best intrinsic activity, which is enhanced by an extensive electrochemical surface area. The woven-like structure of the MoS2 nanotube walls provides a combined effect of strain, crystallinity, and defects. For WS2 structures, the strained surface of the nanotubes results in sites with higher intrinsic activity than the edge sites, but structures such as the nano-triangles, which provide a higher number of edge sites, exhibit competing activity. As for the VS2 structures, although theoretical calculations predict optimal active sites for the hydrogen evolution reaction (HER), they are extremely sensitive to stoichiometry variations that hamper their catalytic activity. Our findings contribute insights to the improvement and design of VS2–based nanocatalysts for the HER and shed light on the general factors that govern the activity in the unique TMD nanotubes family.

Interface engineering of tungsten disulfide by incorporating chromium nitride interfacial layer for hybrid supercapacitors

By confronting the ongoing challenges of energy storage after generation, a unique technology referred to as hybrid energy storage systems appears as a potential solution for energy storage applications. In hybrid supercapacitors, optimizing the electrode characteristics by precise interface engineering greatly improves performance, supporting the device's stability and ability to store charge. The focus of this research is on the interface engineering of tungsten disulfide from the family of transition metal dichalcogenides by the incorporation of chromium nitride interfacial layer of 100 nm on 1 cm2 substrate via magnetron sputtering. The structural characteristics of the resulting samples were acquired using SEM, XRD, Raman, and EDX. The study further employed the half-cell assembly for exploring the electrochemical performance of pure WS2 and WS2 with CrN interfacial layer. The enhanced composition of WS2/CrN was then used as a working electrode alongside activated carbon in a hybrid supercapacitor arrangement. The device reveals a specific capacity, capacitance, power and energy density of 348 C/g, 481.3 F/g, 4250 W/kg and 82.6 Wh/kg, respectively along with capacity retention of 89 % after 10,000 GCD cycles. Following this, the device's performance was evaluated using a semi-empirical approach, comparing capacitive and diffusive mechanisms from linear and quadratic models to study battery-supercapacitor hybrids.

Revealing 1T-MoS2 with 76 % purity induced by various saccharides for supercapacitor performance

The preparation of metallic phase molybdenum disulfide (1T-MoS2) through an implementable method has become a top priority in research due to its excellent electrochemical performance. In this study, 1T-MoS2 using a facile one-pot hydrothermal method is successfully synthesized by incorporating saccharides. Moreover, a comprehensive understanding of the synthesis mechanism is induced by various saccharides. Glucose, a monosaccharide, not only possesses reducibility but also plays a crucial role in preparation of sulfur vacancies. Maltose is a disaccharide that can hydrolyze into glucose and fructose, both of which exhibit reducibility. On the contrary, dextrin is difficult to break down into fructose or glucose, and faces certain challenges in promoting the formation of 1T-MoS2. Importantly, 1T-MoS2 with 76 % purity obtained in our study exhibits exceptional electrochemical performance, demonstrating a high specific capacitance of 228.4 F g−1 at 2 A g−1 and maintaining a cycling stability of 97 % after 10,000 cycles. Furthermore, an asymmetric flexible supercapacitor device is assembled by 1T-MoS2 and active carbon on carbon cloths, which shows superior flexibility, high power density, and energy density. Notably, this work not only unveils the mechanism by which saccharides influence the synthesis of 1T-MoS2 but also provides support for the preparation of other metallic members in the transition metal dichalcogenides (TMDs) family.

Nano tumbleweed-like tungsten disulfide as a viable surrogate for platinum counter electrodes in dye-sensitized solar cells

Tungsten disulfide (WS2), a notable member of the transition metal dichalcogenides family, has emerged as a promising candidate for energy storage and conversion applications. In this study, WS2 was synthesized via a hydrothermal method using sodium tungstate and thiourea as precursor materials, with hydroxylamine hydrochloride as the reducing agent and cetyl trimethyl ammonium bromide as a surfactant. The primary objective was to develop a cost-effective, easily synthesized, and scalable material capable of replacing platinum (Pt) in dye-sensitized solar cells (DSSCs), where Pt is both prohibitively expensive and scarce. Characterization of the synthesized WS2 was conducted through a range of physical analyses, including SEM, TEM, XRD, EDAX, FTIR, and Raman spectroscopy, which provided compelling evidence for the formation of a unique nano-tumbleweed-like structure of WS2. When used as a counter electrode (CE), the synthesized WS2 exhibited exceptional photocatalytic activity, resulting in a commendable power conversion efficiency (PCE) of 12.06 % when coupled with fluorine-doped tin oxide (FTO) plates coated with TiO2 as the photoanode, N719 as the dye, and Iˉ/I3ˉ as the liquid electrolyte. Additionally, the fabricated device underwent comprehensive electrical characterization, including cyclic voltammetry (CV), current-voltage (IV) measurements, electrochemical impedance spectroscopy (EIS), and Tafel analysis, revealing properties similar to those of Pt counter electrodes. Notably, WS2 demonstrated an open-circuit potential of 852 mV and a short-circuit current density of 28 mA/cm2, accompanied by a fill factor of 0.43 and a commendable lifetime of 15.92 ms.

Electronic phase transformations and energy gap variations in uniaxial and biaxial strained monolayer VS[formula omitted] TMDs: A comprehensive DFT and beyond-DFT study

In the rapidly evolving field of 2D materials, transition metal dichalcogenides (TMDs) have emerged as compelling candidates for electronic applications. This study investigates the electronic structure of the H-phase monolayer VS2 belonging to TMD family and the influence of strain on its band structure through Density Functional Theory (DFT). We employ two different pseudopotential approximations and a suite of computational methods including DFT+U, GAUPBE, G0W0, and self-GW to provide a nuanced understanding of its electronic band structure. A highlight of the study is its focus on how both uniaxial and biaxial strains, ranging from -5% to +5%, affect the electronic properties of the H-phase monolayer VS2. Our comprehensive analysis reveals that these tensile strains significantly widen the energy gap, with uniaxial strains having a more pronounced effect than their biaxial counterparts. Additionally, we identify an intriguing phase transition from a semiconducting to a metallic state under compressive strains, this transition is attributed to both symmetry breaking and bond length variation in the uniaxial case, the bond length in biaxial. These key findings not only enrich our understanding of the intricate electronic behavior of monolayer VS2 under different strains but also pave the way for the design of innovative electronic devices using strain engineering.

Study on pH dependent ON/OFF fluorescent switching behaviour of hydrothermally synthesised vanadium disulphide quantum dots (VS2-QDs)

It is fascinating to design and develop an inorganic quantum dot (QDs) which exhibit luminescence features with ion concentration, temperature, and pH sensitivity dependence. Vanadium disulphide (VS2) belongs to the family of transition metal dichalcogenides (TMDs), and is extensively studied owing to its layered characteristics features in sensing and filtrations technology, however, its fluorescence features have not been well studied so far. The current work describes a widely adopted eco-friendly hydrothermal approach for the synthesis of VS2-QDs. The average size of particles was determined to be ∼10 nm by transmission electron microscopy (TEM) and Zetasizer analysis. The synthetic approach adopted here facilitates in situ functionalization of QDs, which results in their high stability in aqueous medium and enhanced sensitivity towards their surroundings. As most of the QDs show the sensitivity towards pH, a thorough investigation of VS2 QDs for their pH dependent photoluminescence has been carried out. The VS2-QDs were discovered to exhibit a remarkable luminescence intensity that was found to be about 11 times higher in basic conditions (pH ∼ 13, QY = ∼4.80 %) as compared to that in acidic conditions (pH ∼ 1, QY = ∼1.10 %). The root cause of this ON/OFF florescence flipping may be related to the functional groups (such as −SO42−, −NH2, OH−, etc.) attached over the surface of QDs, acid etching, and protonation–deprotonation process. This paper highlights the pH dependent switching behaviour of VS2-QDs that could offer valuable information for designing a futuristic pH-based device for biomedical applications.

A comparative study on 2D materials with native high-[formula omitted] oxides for sub-10 nm transistors

Two-dimensional (2D) transition metal dichalcogenides (TMDs) with native high-κ oxides have presented a new avenue towards the development of next-generation ultra-scaled field-effect transistors (FETs). These materials have been experimentally shown to form a natively compatible oxide layer with a high dielectric constant, which can help scale down both the transistor size and the supply voltage. We present a material and device performance study into the use of several of these materials – namely HfS2, HfSe2, ZrS2, ZrSe2 – as channels in sub-10 nm FETs. All four materials exhibit isotropic transport at 10 nm channel length with ON currents over 1000 μA/μm but show anisotropic transport and degraded ON currents at 5 nm channel length. In general, the sulfide family excels in terms of subthreshold characteristics at sub-10 nm channel lengths. HfS2, in particular, surpasses all the other materials in terms of ON currents and subthreshold swing (SS), allowing it to also achieve excellent intrinsic performance. We have identified HfS2 as a superior material within this TMD family for sub-10 nm FETs.

Unveiling the orbital-selective electronic band reconstruction through the structural phase transition in TaTe2

Tantalum ditelluride (TaTe2) belongs to the family of layered transition metal dichalcogenides but exhibits a unique structural phase transition at around 170 K that accompanies the rearrangement of the Ta atomic network from a “ribbon chain” to a “butterfly-like” pattern. While multiple mechanisms including Fermi surface nesting and chemical bonding instabilities have been intensively discussed, the origin of this transition remains elusive. Here we investigate the electronic structure of single-crystalline TaTe2 with a particular focus on its modifications through the phase transition, by employing core-level and angle-resolved photoemission spectroscopy combined with first-principles calculations. Temperature-dependent core-level spectroscopy demonstrates a splitting of the Ta 4f core-level spectra through the phase transition indicative of the Ta-dominated electronic state reconstruction. Low-energy electronic state measurements further reveal an unusual kink-like band reconstruction occurring at the Brillouin zone boundary, which cannot be explained by Fermi surface nesting or band-folding effects. On the basis of the orbital-projected band calculations, this band reconstruction is mainly attributed to the modifications of specific Ta 5d states, namely, the dXY orbitals (the ones elongating along the ribbon chains) at the center Ta sites of the ribbon chains. The present results highlight the strong orbital-dependent electronic state reconstruction through the phase transition in this system and provide fundamental insights towards understanding complex electron-lattice-bond coupled phenomena. Published by the American Physical Society 2024

Room-Temperature Strong Coupling of Few-Exciton in a Monolayer WS2 with Plasmon and Dispersion Deviation.

Engineering room-temperature strong coupling of few-exciton in transition-metal dichalcogenides (TMDCs) with plasmons promises to construct compact and high-performance quantum optical devices. But it remains unimplemented due to their in-plane excitons. Here, we demonstrate the strong coupling of few-exciton within 10 in monolayer WS2 with the plasmonic mode with a large tangential component of the electric field tightly trapped around the sharp corners of an Au@Ag nanocuboid, the fewest number of excitons observed in the TMDC family so far. Furthermore, we for the first time report a significant deviation with a relative difference of up to 100.6% between the spectrum and eigenlevel splitting dispersions, which increases with decreasing coupling strength. It is also shown that the coupling strength obtained by the conventional concept of both being equal to the measured spectrum splitting is markedly overestimated. Our work enriches the understanding of strong light-matter interactions at room temperature.

A comprehensive review on MoSe2 nanostructures with an overview of machine learning techniques for supercapacitor applications.

In the past few decades, supercapacitors (SCs) have emerged as good and reliable energy storage devices due to their impressive power density, better charge-discharge rates, and high cycling stability. The main components of a supercapacitor are its electrode design and composition. Many compositions are tested for electrode preparations, which can provide good performance. Still, research is widely progressing in developing optimum high-performance electrodes. Metal chalcogenides have recently gained a lot of interest for application in supercapacitors due to their intriguing physical and chemical properties, unique crystal structures, tuneable interlayer spacings, broad oxidation states, etc. MoSe2, belonging to the family of Transition Metal Dichalcogenides (TMDs), has also been well explored recently for application in supercapacitors due to its similar properties to 2D materials. In this review, we briefly discuss supercapacitors and their classification. Various available synthesis routes for MoSe2 preparation are summarized. A detailed assessment of the electrochemical performances of different MoSe2 composites, including cyclic voltammetry (CV) analysis and galvanostatic charge-discharge (GCD) analysis, is given for symmetric and asymmetric supercapacitors. The limitations of MoSe2 and its composites are mentioned briefly. The use of machine learning methods and algorithms for supercapacitor applications is discussed for forecasting valuable details. Finally, a summary is provided, along with conclusions.

Emergence of superconductivity by intercalation of alkali metals and alkaline earth metals in Janus transition-metal dichalcogenide heterostructures.

Superconductivity in two-dimensional materials has attracted considerable attention. A new material belonging to the family of Janus transition metal dichalcogenides with out-of-plane structural asymmetry has been recently found to show interesting physical and chemical properties. Using density functional theory and density functional perturbation theory, within the generalized gradient approximation with van der Waals correction, we performed a detailed investigation of the electronic structure, phonon dispersion, Eliashberg spectral function, and electron-phonon coupling of Janus MSSe bilayers (M = Mo or W) and the Janus MoSSe/WSSe heterostructure intercalated with alkali metals (Li, Na, and K) or alkaline earth metals (Mg, Ca, and Sr). We found that the Janus MoSSe bilayer, Janus WSSe bilayer, and Janus MoSSe/WSSe heterostructure transform from a direct band gap semiconductor to a metal or semimetal due to charge transfer from intercalated atoms to the Se and S planes. We showed that all compounds are dynamically stable conventional superconductors. In addition, the Janus heterostructure MoSSe/WSSe intercalated with K exhibits the highest electron-phonon coupling of about 2.12 and the highest superconducting transition temperature of about 14.77 K. Our results indicate the potential application of the Janus materials we investigated in superconductivity.

Enhanced photocatalytic performance of SnS2 under visible light irradiation: strategies and future perspectives.

Tin(II) sulfide (SnS2) has emerged as a promising candidate for visible light photocatalytic materials. As a member of the transition metal dichalcogenides (TMDs) family, SnS2 features a band gap of approximately 2.20 eV and a layered structure, rendering it suitable for visible light activation with a high specific surface area. However, the application of SnS2 as a visible light photocatalyst still requires improvement, particularly in addressing the high recombination of electrons and holes, as well as the poor selectivity inherent in its perfect crystal structure. Therefore, ongoing research focuses on strategies to enhance the photocatalytic performance of SnS2. In this comprehensive review, we analyze recent advances and promising strategies for improving the photocatalytic performance of SnS2. Various successful approaches have been reported, including controlling the reactive facets of SnS2, inducing defects in the crystal structure, manipulating morphologies, depositing noble metals, and forming heterostructures. We provide a detailed understanding of these phenomena and the preparation techniques involved, as well as future considerations for exploring new science in SnS2 photocatalysis and optimizing performance.