Van Der Waals Contacts Research Articles

Engineering van der Waals Contacts by Interlayer Dipoles.

Tuning the interfacial Schottky barrier with van der Waals (vdW) contacts is an important solution for two-dimensional (2D) electronics. Here we report that the interlayer dipoles of 2D vdW superlattices (vdWSLs) can be used to engineer vdW contacts to 2D semiconductors. A bipolar WSe2 with Ba6Ta11S28 (BTS) vdW contact was employed to exhibit this strategy. Strong interlayer dipoles can be formed due to charge transfer between the Ba3TaS5 and TaS2 layers. Mechanical exfoliation breaks the superlattice and produces two distinguished surfaces with TaS2 and Ba3TaS5 terminations. The surfaces thus have opposite surface dipoles and consequently different work functions. Therefore, all the devices fall into two categories in accordance with the rectifying direction, which were verified by electrical measurements and scanning photocurrent microscopy. The growing vdWSL family along with the addition surface dipoles enables prospective vdW contact designs and have practical application in nanoelectronics and nano optoelectronics.

Crystal structure of the Mycobacterium tuberculosis VirS regulator reveals its interaction with the lead compound SMARt751

Ethionamide (ETO) is a prodrug that is primarily used as a second-line agent in the treatment of tuberculosis. Among the bacterial ETO activators, the monooxygenase MymA has been recently identified, and its expression is regulated by the mycobacterial regulator VirS. The discovery of VirS ligands that can enhance mymA expression and thereby increase the antimycobacterial efficacy of ETO, has led to the development of a novel therapeutic strategy against tuberculosis. This strategy involves the selection of preclinical candidates, including SMARt751. We report the first crystal structure of the AraC-like regulator VirS, in complex with SMARt751, refined at 1.69 Å resolution. Crystals were obtained via an in situ proteolysis method in the requisite presence of SMARt751. The elucidated structure corresponds to the ligand-binding domain of VirS, adopting an α/β fold with structural similarities to H-NOX domains. Within the VirS structure, SMARt751 is situated in a completely enclosed hydrophobic cavity, where it forms hydrogen bonds with Asn11 and Asn149 as well as van der Waals contacts with various hydrophobic amino acids. Comprehensive structural comparisons within the AraC family of transcriptional regulators are conducted and analyzed to figure out the effects of the SMARt751 binding on the regulatory activity of VirS.

Molecular crystals of 2-methyl-1H-benzo[d]imidazole and pyridine-2,6-dimethanol with chloranilic, trimesic and gallic acid

Crystallization experiments of 2-methyl-1H-benzo[d]imidazole (MBI) and pyridine-2,6- dimethanol (PDM) with chloranilic (CLA), trimesic (TMA) and gallic acid (GA) yielded a total of ten multicomponent molecular crystals in salt form, i.e., MBI:CLA (1), 2MBI:CLA:2H2O (2), 2MBI:CLA:3H2O (3A), 2MBI:CLA:3H2O (3B), 2MBI:CLA:4H2O (4), MBI:TMA (5), MBI:GA:3.4H2O (6), PDM:CLA (7), PDM:CLA:H2O (8), and 2PDM:CLA (9), of which compounds 3A and 3B are polymorphs. Characteristic for the crystal structures of all compounds except for 7 is the presence of heterosynthons formed between the molecular components by charge-assisted NHMBI/PDM⋯OCLA/TMA/GA hydrogen bonds, which are mostly bifurcated. In compound 7, the positively charged NH groups are involved in the formation of PDM-PDM homodimers interacting through NHPDM⋯OPDM hydrogen bonds. The series of compounds having 2:1 MBI/PDM:CLA ratio (2, 3A, 3B, 4 and 9) comprise trimeric molecular units of the composition MBI-CLA-MBI or PDM-CLA-PDM, respectively, based on charge-assisted bifurcated NH⋯O hydrogen bonds. Despite the directionality of these interactions, the units have certain flexibility consisting in mutual bending of the aromatic ring planes and are considered interesting building blocks for crystal engineering purposes. Except for compound 9, all crystal structures exhibit π⋯π interactions involving the positively charged benzimidazolium and pyridinium rings of protonated MBI and PDM and/or the π-delocalized sections in the organic anions. The water molecules in hydrates 2, 3A, 3B, 4, 6 and 8 exercise mostly crystal lattice stabilizing functions by interconnecting the synthons established among the organic components. Hirshfeld surface and fingerprint analysis revealed that O⋯H/H⋯O interactions and van der Waals contacts are dominant in conjunct with Cl⋯H/H⋯Cl contacts in the compounds derived from CLA.

N-Benzoyl-morpholine-4-carbothioamides: Crystal structures, Hirshfeld surface analysis, and Density functional theory calculations

The current research work describes facile synthesis, single crystal X-ray structures, Hirshfeld surface (HS) analysis, and density functional theory (DFT) calculations of two N-benzoyl-morpholine-4-carbothioamides (NDMC and NMMC). Consequently, the synthesized compounds, C12H12Cl2N2O2S (NDMC) and C13H16N2O2S (NMMC) crystallized in triclinic and monoclinic crystal systems each having respective space groups of P -1 and P 21, with corresponding a = 7.8045 (3) Å, b = 12.8458 (6) Å, c = 13.4946 (7) Å, α = 97.313 (4)°, β = 94.358 (4)°, γ = 93.348 (3)°, Z = 4 and V = 1334.84 (11) Å3 for compound (NDMC). Similarly, for compound (NMMC),a = 7.3322 (2) Å, b = 5.3045 (1) Å, c = 16.3367 (5) Å, α = 90°, β = 94.285 (3)°, γ = 90°, Z = 2 and V = 633.62 (3) Å3. Subsequently, the asymmetric unit of compound (NDMC) contains two molecules, while compound (NMMC) has single molecule. Strong intermolecular NH⋯O, and weaker CH⋯Cl and CH⋯S hydrogen bonds link the molecules of (NDMC) into dimers, enclosing R22(7) and R22(9) ring motifs. Intermolecular CH⋯S, bifurcated NH⋯O and CH⋯O hydrogen bonds, as well as CH⋯π interactions in (NMMC), attach molecules, enclosing R22(7) and R22(14) ring motifs. Furthermore, HS analysis explored, visualized, and quantified the significance of hydrogen bond contacts, and revealed active contributions for the packed crystals encompasses H…H 33.6 % for (NDMC), and 46.6 % for (NMMC), H…S/S…H 17.9 % for (NDMC), and 17.0 % for (NMMC), H…C/C…H 9.0 % for (NDMC), and 19.7 % for (NMMC), H…O/O…H 14.8 % for (NDMC), and 14.3 % for (NMMC), and H…Cl/Cl…H 17.8 % for (NMMC). Hydrogen bonding and van der Waals contacts strongly influence crystal packings of the crystallized compounds. Similarly, evaluation of energy frameworks (electrostatic, dispersion and total energies) indicated stabilization is strongly dominated by dispersion energy contribution in compound (NMMC). Finally, optimum molecular structures of both the compounds (NDMC and NMMC), were related with the experimental ones employing DFT at B3LYP/6–311G**(d,p) level. The most stable optimized conformation was geometrically complementary with the crystal structure. DFT computed frontier molecular energies and isodensities predicted these compounds to exhibit better electron pair acceptance nature than electron pair donor.

Multi-Layer Palladium Diselenide as a Contact Material for Two-Dimensional Tungsten Diselenide Field-Effect Transistors.

Tungsten diselenide (WSe2) has emerged as a promising ambipolar semiconductor material for field-effect transistors (FETs) due to its unique electronic properties, including a sizeable band gap, high carrier mobility, and remarkable on-off ratio. However, engineering the contacts to WSe2 remains an issue, and high contact barriers prevent the utilization of the full performance in electronic applications. Furthermore, it could be possible to tune the contacts to WSe2 for effective electron or hole injection and consequently pin the threshold voltage to either conduction or valence band. This would be the way to achieve complementary metal-oxide-semiconductor devices without doping of the channel material.This study investigates the behaviour of two-dimensional WSe2 field-effect transistors with multi-layer palladium diselenide (PdSe2) as a contact material. We demonstrate that PdSe2 contacts favour hole injection while preserving the ambipolar nature of the channel material. This consequently yields high-performance p-type WSe2 devices with PdSe2 van der Waals contacts. Further, we explore the tunability of the contact interface by selective laser alteration of the WSe2 under the contacts, enabling pinning of the threshold voltage to the valence band of WSe2, yielding pure p-type operation of the devices.

Virtual screening of the biological activity of fatty acid amides

3D modeling of fatty acid amides was carried out in order to study their bioavailability indicators. Fatty acid amide complexes with the PPARα receptor were constructed by molecular docking. It was shown that fatty acid amides, based on Lipinsky’s rule of five, due to their low solubility in water, high lipophilicity and flexibility, have weak bioavailability, which limits their digestibility when taken orally. As a result of docking fatty acid amides with the PPARα receptor, stable complexes are formed. They are characterized by the presence of hydrogen bonds and a network of Van der Waals contacts.

Van der Waals Contact for Two-Dimensional Transition Metal Dichalcogenides.

Two-dimensional (2D) transition metal dichalcogenides (TMDs) have emerged as highly promising candidates for next-generation electronics owing to their atomically thin structures and surfaces devoid of dangling bonds. However, establishing high-quality metal contacts with TMDs presents a critical challenge, primarily attributed to their ultrathin bodies and delicate lattices. These distinctive characteristics render them susceptible to physical damage and chemical reactions when conventional metallization approaches involving "high-energy" processes are implemented. To tackle this challenge, the concept of van der Waals (vdW) contacts has recently been proposed as a "low-energy" alternative. Within the vdW geometry, metal contacts can be physically laminated or gently deposited onto the 2D channel of TMDs, ensuring the formation of atomically clean and electronically sharp contact interfaces while preserving the inherent properties of the 2D TMDs. Consequently, a considerable number of vdW contact devices have been extensively investigated, revealing unprecedented transport physics or exceptional device performance that was previously unachievable. This review presents recent advancements in vdW contacts for TMD transistors, discussing the merits, limitations, and prospects associated with each device geometry. By doing so, our purpose is to offer a comprehensive understanding of the current research landscape and provide insights into future directions within this rapidly evolving field.

Probing the interaction of an antiviral drug 8-methoxy-3-nitro-2-(4-methoxyphenyl)-2H-chromene (MNC) with DNA by experimental and computational approach

Deoxyribonucleic acid (DNA) is a major target in research pertaining to antiviral and anticancer therapies since it is the principal genetic material that controls vital biological functions. The complex relationship between calf thymus DNA (ct-DNA) and 8-Methoxy-3-nitro-2-(4-methoxyphenyl)-2H-chromene (MNC), an anticancer drug derivative of 2-aryl-3-nitro-2H-chromenes, is explored in this work. Using various spectroscopic methods such as fluorescence, circular dichroism (CD), UV–visible, isothermal titration calorimetry (ITC) experiment, and molecular docking calculations, this study elucidates the binding characteristics and affinity between MNC and ct-DNA. Through predominant groove binding and moderate intercalation, MNC demonstrates a complicated binding pattern with DNA at the minor groove, as shown by the UV–Vis spectra and emission-based dye displacement investigations. DNA undergoes a little conformational change that MNC induces, as shown by CD spectroscopy. The thermodynamics parameters such as the binding constant, binding enthalpy, and binding free energy of DNA-MNC interaction, as calculated by the ITC experiment, were approximately ∼ 104 M−1, −26 kcal mol−1, and 6 kcal/mol, respectively. The binding process is enthalpy driven implying a stabilizing contact of MNC with DNA and the entropic penalty (−TΔS = +20.1 kcal mol−1) points to a reduction in the degree of freedom of movement. The molecular docking investigation also estimates the similar interaction energy and binding locations of MNC with DNA. Interestingly, MNC attaches to the surface of the DNA via electrostatic interactions; a stronger attachment through van der Waals and hydrophobic contacts within the minor groove follows this. These studies are anticipated to provide researchers with important direction for designing new drug molecules for further biomolecular investigations.

Contacts at the Nanoscale and for Nanomaterials.

Contact scaling is a major challenge in nano complementary metal-oxide-semiconductor (CMOS) technology, as the surface roughness, contact size, film thicknesses, and undoped substrate become more problematic as the technology shrinks to the nanometer range. These factors increase the contact resistance and the nonlinearity of the current-voltage characteristics, which could limit the benefits of the further downsizing of CMOS devices. This review discusses issues related to the contact size reduction of nano CMOS technology and the validity of the Schottky junction model at the nanoscale. The difficulties, such as the limited doping level and choices of metal for band alignment, Fermi-level pinning, and van der Waals gap, in achieving transparent ohmic contacts with emerging two-dimensional materials are also examined. Finally, various methods for improving ohmic contacts' characteristics, such as two-dimensional/metal van der Waals contacts and hybrid contacts, junction doping technology, phase and bandgap modification effects, buffer layers, are highlighted.

Room Temperature Negative Differential Resistance with High Peak Current in MoS2/WSe2 Heterostructures.

Two-dimensional transition metal dichalcogenide (2D TMD) semiconductors allow facile integration of p- and n-type materials without a lattice mismatch. Here, we demonstrate gate-tunable n- and p-type junctions based on vertical heterostructures of MoS2 and WSe2 using van der Waals (vdW) contacts. The p-n junction shows negative differential resistance (NDR) due to Fowler-Nordheim (F-N) tunneling through the triangular barrier formed by applying a global back-gate bias (VGS). We also show that the integration of hexagonal boron nitride (h-BN) as an insulating tunnel barrier between MoS2 and WSe2 leads to the formation of sharp band edges and unintentional inelastic tunnelling current. The devices based on vdW contacts, global VGS, and h-BN tunnel barriers exhibit NDR with a peak current (Ipeak) of 315 μA, suggesting that the approach may be useful for applications.

Metal Films on Two-Dimensional Materials: van der Waals Contacts and Raman Enhancement.

Electronic devices based on two-dimensional (2D) materials will need ultraclean and defect-free van der Waals (vdW) contacts with three-dimensional (3D) metals. It is therefore important to understand how vdW metal films deposit on 2D surfaces. Here, we study the growth and nucleation of vdW metal films of indium (In) and non-vdW metal films of gold (Au), deposited on 2D MoS2 and graphene. In follows a 2D growth mode in contrast to Au that follows a 3D growth mode. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to image the morphology of metal clusters during growth and quantify the nucleation density. As compared to Au, In atoms exhibit nearly 50 times higher diffusivity (3.65 × 10-6 μm-2 s-1) and half the nucleation density (64.9 ± 2.46 μm-2), leading to larger grain sizes (∼60 nm for 5 nm In on monolayer MoS2). The grain size of In can be further increased by reducing the 2D surface roughness, while the grain size for Au is limited by its high nucleation density due to the creation of interface defects during deposition. The vdW gap between In and MoS2 and graphene leads to strong enhancement (>103) in their Raman signal intensity due to localized surface plasmon resonance. In the absence of a vdW gap, the plasmon-mediated enhancement in Raman does not occur.

ENDOR Spectroscopy Reveals the "Free" 5'-Deoxyadenosyl Radical in a Radical SAM Enzyme Active Site Actually is Chaperoned by Close Interaction with the Methionine-Bound [4Fe-4S]2+ Cluster.

1/2H and 13C hyperfine coupling constants to 5'-deoxyadenosyl (5'-dAdo•) radical trapped within the active site of the radical S-adenosyl-l-methionine (SAM) enzyme, pyruvate formate lyase-activating enzyme (PFL-AE), both in the absence of substrate and the presence of a reactive peptide-model of the PFL substrate, are completely characteristic of a classical organic free radical whose unpaired electron is localized in the 2pπ orbital of the sp2 C5'-carbon (J. Am. Chem. Soc. 2019, 141, 12139-12146). However, prior electron-nuclear double resonance (ENDOR) measurements had indicated that this 5'-dAdo• free radical is never truly "free": tight van der Waals contact with its target partners and active-site residues guide it in carrying out the exquisitely precise, regioselective reactions that are hallmarks of RS enzymes. Here, our understanding of how the active site chaperones 5'-dAdo• is extended through the finding that this apparently unexceptional organic free radical has an anomalous g-tensor and exhibits significant 57Fe, 13C, 15N, and 2H hyperfine couplings to the adjacent, isotopically labeled, methionine-bound [4Fe-4S]2+ cluster cogenerated with 5'-dAdo• during homolytic cleavage of cluster-bound SAM. The origin of the 57Fe couplings through nonbonded radical-cluster contact is illuminated by a formal exchange-coupling model and broken symmetry-density functional theory computations. Incorporation of ENDOR-derived distances from C5'(dAdo•) to labeled-methionine as structural constraints yields a model for active-site positioning of 5'-dAdo• with a short, nonbonded C5'-Fe distance (∼3 Å). This distance involves substantial motion of 5'-dAdo• toward the unique Fe of the [4Fe-4S]2+ cluster upon S-C(5') bond-cleavage, plausibly an initial step toward formation of the Fe-C5' bond of the organometallic complex, Ω, the central intermediate in catalysis by radical-SAM enzymes.

Switching the on-surface orientation of oxygen-functionalized helicene.

Helicenes represent an important class of chiral organic material with promising optoelectronic properties. Hence, functionalization of surfaces with helicenes is a key step toward new organic materials devices. The deposition of a heterohelicene containing two furano groups and two hydroxyl groups onto copper(111) surface in ultrahigh vacuum leads to different adsorbate modifications. At low coverage and low temperature, the molecules tend to lie on the surface in order to maximize van der Waals contact with the substrate. Thermal treatment leads to deprotonation of the hydroxyl groups and in part into a reorientation from lying into a standing adsorbate mode.

Interface thermal conductivities induced by van der Waals interactions.

The interface heat transfer of two layers induced by van der Waals (vdW) contacts is theoretically investigated, based on first-principles calculations at low temperatures. The results suggest that out-of-plane acoustic phonons with low frequencies dominate the interface thermal transport due to the vdW interaction. The interface thermal conductivity is proportional to the cubic of temperature at very low temperatures, but becomes linearly proportional to temperature as temperature increases. We show that manipulating the strain alters vdW coupling, leading to increased interfacial thermal conductivity at the interface. Our findings provide valuable insights into the interface heat transport in vdW heterostructures and support further design and optimization of electronic and optoelectronic nanodevices based on vdW contacts.

Base flipping mechanism and binding strength of methyl-damaged DNA during the interaction with AGT.

Methyl damage to DNA bases is common in the cell nucleus. O6-alkylguanine-DNA alkyl transferase (AGT) may be a promising candidate for direct damage reversal in methylated DNA (mDNA) at the O6 point of the guanine. Indeed, atomic-level investigations in the contact region of AGT-DNA complex can provide an in-depth understanding of their binding mechanism, allowing to evaluate the silico-drug nature of AGT and its utility in removing methyl damage in DNA. In this study, molecular dynamics (MD) simulation was utilized to examine the flipping of methylated nucleotide, the binding mechanism between mDNA and AGT, and the comparison of binding strength prior and post methyl transfer to AGT. The study reveals that methylation at the O6 atom of guanine weakens the hydrogen bond (H-bond) between guanine and cytosine, permitting for the flipping of such nucleotide. The formation of a H-bond between the base pair of methylated nucleotide (i.e., cytosine) and the intercalated arginine of AGT also forces the nucleotide to rotate. Following that, electrostatics and van der Waals contacts as well as hydrogen bonding contribute to form the complex of DNA and protein. The stronger binding of AGT with DNA before methyl transfer creates the suitable condition to transfer methyl adduct from DNA to AGT.

Design of ohmic contacts between Janus MoSSe and two-dimensional metals

Two-dimensional semiconductors are considered as channel materials for field-effect transistors to overcome short-channel effects and reduce the device size. As the contacts to the metallic electrodes are decisive for the device performance, we study the electronic properties of contacts between Janus MoSSe and various two-dimensional metals. We demonstrate that weak interactions at these van der Waals contacts suppress Fermi level pinning and show that ohmic contacts can be formed for both terminations of Janus MoSSe, generating favorable transport characteristics.

Truncated derivatives of amphidinol 3 reveal the functional role of polyol chain in sterol-recognition and pore formation

Here we examined the membrane binding and pore formation of amphidinol 3 (AM3) and its truncated synthetic derivatives. Importantly, both of the membrane affinity and pore formation activity were well correlated with the reported antifungal activity. Our data clearly demonstrated that the C1-C30 moiety of AM3 plays essential roles both in sterol recognition and stable pore formation. Based on the current findings, we updated the interacting model between AM3 and sterol, in which the moiety encompassing from C21 to C67 accommodates a sterol molecule with forming hydrogen bonds with the sterol hydroxy group and van der Waals contact between AM3 polyol and sterol skeleton. Although the conformation of the C1-C20 moiety of AM3 is hard to specify due to its flexibility, the region likely contributes to stabilization of pore structure.

Benzylpyrazolyl naphthoquinones as potential VEGFR-2, GPCR and PPAR inhibitors: Synthesis, anti-cancer evaluation, molecular docking and DFT studies

The present study reports the synthesis of benzylpyrazolyl naphthoquinones using nano-Fe3O4 supported Bronsted acidic ionic liquid ([nano-Fe3O4@BenzImi]SO3H) as magnetically retrievable solid acid catalyst. In vitro anti-cancer activity of the synthesized benzylpyrazolyl naphthoquinones have been evaluated against breast cancer cell line (MCF-7) and liver cancer cell line (HepG2). Compound 4h was found to be the most active compounds with IC50 values 0.0436±0.31 µM against MCF 7 cell line whereas compound 4e was displayed highest activity with IC50 values 0.0314±0.16 µM against HepG2 cell line as compared to the standard 5-fluorouracil (0.0384±0.10 and 0.0330±0.09 µM). Furthermore, in silico bioactivity studies revealed that the compounds have significant interactions with the drug targets. The molecular docking studies revealed that the compounds have significant binding affinity with potential receptors such as vascular endothelial growth factor receptor (VEGFR-2), G-protein coupled receptor (GPCR) and peroxisome proliferator-activated receptors (PPAR). The compound 4g has strong hydrogen bond interaction with VEGFR-2 as well as the lowest binding energy (-9.3 kcal/mol−1), similarly, 4c has strong hydrogen bond interaction with in GPCR as well as the lowest binding energy (-7.8 kcal/mol−1) whereas 4a and 4e show strong hydrogen bond interaction with in PPAR as well as lowest binding energy (-10.1 kcal/mol−1 and -10.1 kcal/mol−1) as compared to other compounds. The docking studies revealed that these compounds gets stabilized via hydrogen bonding interactions, van der Waals contacts and electrostatic interactions which were further supported through estimation of HOMO-LUMO energies, ionization potential, electron affinities, dipole moment etc. using density functional theory (DFT) analysis. The work highlights biological significance of benzylpyrazolyl naphthoquinones as a potential anti-cancer reagent.

A quad-core Zn (II) cluster-based microporous metal-organic framework with nonpolar cages for efficient removal of ethane from ethane/ethylene mixtures

Ethane (C2H6) and ethylene (C2H4) have similar physical and chemical properties, which are critical and difficult for the separation of C2H6/C2H4 mixtures in the petrochemical process. Traditional C2H4-selective adsorbents can separate the C2H6/C2H4 mixtures, but need further desorption treatment to obtain pure C2H4 production. On the contrary, high-pure C2H4 can be prepared in one step by C2H6-selective porous material. Herein, we present a caged metal-organic framework (GNU-2) based on Zn (II) clusters, which has advantageous adsorption sites and cavity pockets for the reverse capture of C2H6 from C2H6/C2H4 mixtures. At 298 K and 1 bar, high C2H6 uptake (5.10 mmol g−1) and C2H6/C2H4 selectivity (1.849) were attained based on the activated GNU-2 (GNU-2a), exceeding a number of top C2H6-selective adsorbents. Grand canonical Monte Carlo (GCMC) simulations exhibit that the appropriate chemical environment of nonpolar cage in GNU-2a allows it to continuously maintain closer van der Waals contacts between C2H6 molecule, saturated Zn cluster and nonpolar pore surface through multiple CH···O hydrogen interactions and CH···π hydrogen interactions. Moreover, dynamic breakthrough studies also show that GNU-2a displays the actual separation performances of C2H6.

High‐performance MoS2 Homojunction Photodiode Enabled by Facile Van der Waals Contacts with 2D Perovskite

Abstractp–n junction, as an important part of modern electronics and integrated circuits, is the basis of various functional devices. Compared with heterojunctions, 2D p–n homojunctions preclude interface problems and have greater potential in ultra‐sensitive photodetection. Here, through simple van der Waals contacts with a 2D perovskite layer, it is realized efficient p‐type doping of MoS2 and constructed a high‐performance photodiode based on MoS2 homogeneous p–n junction. The dark current is as low as 10−12 A, with an ideality factor of 1.3. Under illumination, the open circuit voltage of the device can reach up to 0.7 V. In addition, under zero bias, the device exhibits a high responsivity of 529 mA W−1 and a fast response time of 105/109 µs. This work not only provides a facile and stable method to construct the MoS2 p–n homojunction but also opens up possibilities for new‐type 2D‐based optoelectronic devices and technologies.