MoS2-based Heterostructures Research Articles

Significant promotion of interlayer ion diffusion for MoS2 /MoBS heterostructure as high performance Li/Na ion batteries anode material

As a member of the new two-dimensional materials family, functionalized MoB (MBene) attracts great interest as energy storage materials due to their excellent mechanical properties and metallicity. Here, we aim to leverage the superior properties of MBene to develop new promising electron materials for Li/Na-ion batteries by designing the MoS2 /MoBS heterostructure. Our investigation focuses on the structural stability, mechanical and electrochemical properties by first-principles calculation. The high Young's modulus, robust structural stability and metallicity prevent the electrode pulverization and guarantee cycle stability of battery. Impressively, the interlayer diffusion barriers of Li and Na atoms are only 0.26 and 0.16 eV, outperforming other MoS2-based heterostructures. With calculated open circuit voltage of 0.01–1.83 V for Li atoms and 0.02–1.28 V for Na atoms, the heterostructure is suitable for deployment as an anode material. Besides, the reversible specific capacity (376 mAh/g) of Li atoms is improved by the electron transfer caused by the formation of heterostructure compared to that of monolayer MoS2 (335 mAh/g) and MoBS(193 mAh/g). These findings fully underline the potential of MoS2/MoBS heterostructure as anode material of Li/Na-ion batteries.

Optimally arranged TiO2@MoS2 heterostructures with effectively induced built-in electric field for high-performance lithium-sulfur batteries

To overcome the serious technological issues affecting lithium-sulfur (Li-S) batteries, such as sluggish sulfur redox kinetics and the detrimental shuttle effect, heterostructure engineering has been investigated as a strategy to effectively capture soluble lithium polysulfide intermediates and promote their conversion reaction by integrating highly polar metal oxides with catalytically active metals sulfides. However, to fully exploit the outstanding properties of heterostructure-based composites, their detailed structure and interfacial contacts should be designed rationally. Herein, optimally arranged TiO2 and MoS2-based heterostructures (TiO2@MoS2) are fabricated on carbon cloth as a multifunctional interlayer to efficiently trap polysulfide intermediates and accelerate their redox kinetics. Owing to the synergistic effects between TiO2 and MoS2 and the uniform heterointerface distribution that induces the ideally oriented built-in electric field, Li-S batteries with TiO2@MoS2 interlayers exhibit high rate capability (601 mA h g−1 at 5 C), good cycling stability (capacity-fade rate of 0.067% per cycle over 500 cycles at 2 C), and satisfactory areal capacity (5.2 mA h cm−2) under an increased sulfur loading of 5.2 mg cm−2. Moreover, by comparing with a MoS2@TiO2 interlayer composed of reversely arranged heterostructures, the effect of the built-in electric field’s direction on the electrocatalytic reactions of polysulfide intermediates is thoroughly investigated for the first time. The superior electrocatalytic activities of the rationally arranged TiO2@MoS2 interlayer demonstrate the importance of optimizing the built-in electric field of heterostructures for producing high-performance Li-S batteries.

Broadband photodetection using one-step CVD-fabricated MoS2/MoO2 microflower/microfiber heterostructures

Molybdenum disulfide (MoS2) has been combined so far with other photodetecting semiconductors as an enhancing agent owing to its optical and electronic properties. Existing approaches demonstrated MoS2-incorporated photodetector devices using complex and costly fabrication processes. Here, we report on simplified one-step on the chemical vapor deposition (CVD) based synthesis of a unique microfiber/microflower MoS2-based heterostructure formed by capturing MoO2 intermediate material during the CVD process. This particular morphology engenders a material chemical and electronic interplay exalting the heterostructure absorption up to ~ 98% over a large spectral range between 200 and 1500 nm. An arsenal of characterization methods were used to elucidate the properties of these novel heterostructures including Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectrometry, high-resolution transmission and scanning electron microscopies, and Kelvin probe force microscopy. Our findings revealed that the MoS2 and the MoO2 crystallize in the hexagonal and monoclinic lattices, respectively. The integration of the MoS2/MoO2 heterostructures into functional photodetectors revealed a strong photoresponse under both standard sun illumination AM1.5G and blue light excitation at 450 nm. Responsivity and detectivity values as high as 0.75 mA W−1 and 1.45 × 107 Jones, respectively, were obtained with the lowest light intensity of 20 mW cm−2 at only 1 V bias. These results demonstrate the high performances achieved by the unique MoS2/MoO2 heterostructure for broadband light harvesting and pave the way for their adoption in photodetection applications.

Carbothermal-reduction-assisted CVD synthesis of layered MoS2 nanosheets on activated carbon support: Implication for photocatalysis

The photocatalytic activity of MoS2-based heterostructures largely depends on the thickness and orientation of the MoS2 components. We report a new facile two-step carbothermal-reduction-assisted CVD synthesis protocol to produce horizontally and vertically aligned MoS2 nanosheets (NSs) on activated carbon (AC) granules. MoO3/AC pellets were first prepared by sonicating MoO3 and AC powders and then used as a substrate and Mo source to obtain MoS2/AC composites. A feature of the process is that MoO3 particles, prior to interaction with sulfur, undergo carbothermal reduction with the formation of Mo suboxides favorable for MoS2 growth. The thickness and orientation of MoS2 NSs strongly depend on the synthesis temperature. At 600 °C, horizontally oriented triangular MoS2 NSs are formed on the surface of molybdenum oxide particles, and at 700 °C, thin vertically oriented MoS2 NSs with a high aspect ratio (with a thickness and a lateral size of 20 × 5000 nm2) are grown. The high photocatalytic activity of MoS2/AC composites during the decompositions of organic dyes under UV radiation is associated with the thickness and orientation of MoS2 NSs. The vertical arrangement of the active edges intensifies the chemical interaction with the reagents, and the small NS thickness prevents the recombination of charge carriers and facilitates their transfer to the surface. The obtained results open up new possibilities for the development of cost-effective and scalable MoS2-based photocatalysts with tunable thickness and orientation of MoS2 NSs on commercially available AC substrates using a carbothermal-reduction-assisted CVD approach.

MoS2-based multiple surface plasmonic coupling for enhanced surface-enhanced Raman scattering and photoelectrocatalytic performance utilizing the size effect.

MoS2-based heterostructures have received increasing attention for not only surface-enhanced Raman scattering (SERS) but also for enhanced photoelectrocatalytic (PEC) performance. This study presents a hydrothermal method for preparing vertical MoS2 nanosheets composed of in situ grown AuNPs with small size and chemically reduced AgNPs with large size to achieve the synergistic enhancement of SERS and PEC properties owing to the size effect of the plasmonic structure. Compared with pristine MoS2 nanosheets and unitary AuNPs or AgNPs composited with MoS2 nanosheets, the ternary heterostructure exhibited the strongest electromagnetic field and surface plasmon coupling, which was confirmed by finite-difference time-domain (FDTD) simulation and absorption spectra. In addition, the experimental results confirmed the outstanding SERS enhancement with an EF of 1.1×109, and the most efficient hydrogen evolution reaction (HER) activity with a sensitive photocurrent response, attributing to the multiple surface plasmonic coupling effects of the Au-Ag bimetal and efficient charge-transfer process between MoS2 and the bimetal. That is, it provides a robust method for developing multi-size bimetal-semiconductor complex nanocomposites for high-performance SERS sensors and PEC applications.

Facile synthesis of MoS2/Ni2V3O8 nanosheets for pH-universal efficient hydrogen evolution catalysis

MoS2 presents an attractive performance for the hydrogen evolution reaction (HER) in acidic environment. However, its worse catalytic performance in neutral and alkaline media is problematic for practical application. Herein, stable MoS2/Ni2V3O8 nanosheets are synthesized by a facile hydrothermal method, which exhibit enhanced HER activities in all pH solutions as opposed to the pristine MoS2 and Ni2V3O8. The overpotentials are 48, 52, and 68 mV at 10 mA cm−2 with small Tafel slopes of 46, 54, and 55 mV dec−1 in alkaline, acidic and neutral media, respectively, which are competitive to that of Pt/C. The superior HER activity is due to the defective lattices, suitable interface band alignment, as well as the synergistic effect between MoS2 and Ni2V3O8. First-principles calculations show that the electronic coupling at the interface results in enhanced electronic conductivity, optimal hydrogen adsorption and water dissociation free energies. This work demonstrates that rational design of unique MoS2-based heterostructures can effectively improve their HER activities, which holds great potential for practical applications in pH-universal overall water splitting.

Theoretical Study on Tuning Band Gap and Electronic Properties of Atomically Thin Nanostructured MoS2/Metal Cluster Heterostructures.

Nano-heterostructures have attracted immense attention recently due to their remarkable interfacial properties determined by the heterointerface of different nanostructures. Here, using first-principles density functional theory (DFT) calculations, we examine what range the variable electronic properties such as the electronic band gap can be tuned by combining two dissimilar nanostructures consisting of atomically thin nanostructured MoS2 clusters with small silver and gold nanoparticles (Ag/Au NPs). Most interestingly, our calculations show that the electronic band gap of the nanostructured MoS2 cluster can be tuned from 2.48 to 1.58 and 1.61 eV, by the formation of heterostructures with silver and gold metal nanoclusters, respectively. This band gap is ideal for various applications ranging from flexible nanoelectronics to nanophotonics applications. Furthermore, the adsorption of H2 molecules on both nano-heterostructures is investigated, and the computed binding energies are found to be within the desirable range. The reported theoretical results provide inspiration for engineering various optoelectronic applications for nanostructured MoS2-based heterostructures.

Nanocrystalline NiSe2/MoS2 heterostructures for electrochemical hydrogen evolution reaction

Although it suffers from a heavy dependence on the noble platinum catalyst, the electrochemical hydrogen evolution reaction (HER) is one of the most promising methods for the production of hydrogen. After numerous efforts, it is found that MoS2-based heterostructure may replace platinum as the electrochemical HER catalyst. In this work, the nanocrystalline NiSe2/MoS2 heterostructures were successfully prepared on the carbon fiber paper (CFP) substrate through electrochemical deposition and hydrothermal process. According to a series of electrochemical HER tests and a comparison with other MoS2-based heterostructure catalysts, the CFP/NiSe2/MoS2 catalyst with an overpotential η 10 of 143 mV and a Tafel slope of 45 mV dec−1 exhibited an excellent electrochemical HER catalytic performance and durability. In addition, CFP/NiSe2/MoS2 catalyst was treated by plasma to further improve the catalytic performance of the catalyst.

Novel molybdenum disulfide heterostructure nanohybrids with enhanced visible-light-induced photocatalytic activity towards organic dyes

The present investigation reports on research of pure molybdenum disulfide (MoS2) and MoS2 doped CoO@meso-CN nanohybrids with various concentration. The photocatalytic action of MoS2 doped CoO@meso-CN nanohybrids was established by photodegrading methylene red (MR), methylene orange (MO) and congo red (CR) under visible light irradiation. The efficient visible light driven photocatalytic action was owing to a larger specific surface area of MoS2, which enhanced the close interfacial contact between pollutants and photocatalysts. Thus, when employed as photocatalyst for organic pollutants photodegradation, the developed nanohybrid exhibits a degradation rate of 0.072 min−1, which is high increasing compared with that of pure CoO/meso-CN and MoS2 (0.014 min−1 and 0.032 min−1). In addition, the nanohybrids indicates excellent stability and remarkable organic dyes removal capability, which could provide as a potential photocatalyst for water remediation under visible light. The resultant MoS2 doped CoO@meso-CN nanohybrids exhibit excellent photocatalytic capacity for MR, MO and CR (average removal rate was 94% at pH values of 3) within 60 min. The following demonstrated that synthesized MoS2 doped 1 wt% CoO@meso-CN nanohybrids retained a great photocatalytic as compared to pure MoS2 and CoO/meso-CN photocatalysts for degradation of organic dyes. The cases were described using XRD, FESEM, FTIR, HRTEM, XPS, TGA, UV–vis, Raman and EPR spectroscopy analyses. Our results serve a pathway for the fabrication of a MoS2-based heterostructure nanohybrids which can be applied for environmental management and reusability regions.

(Invited) Controlling Defects and Oxidation at Molybdenum Disulfide Electrodes and the Impact on Capacitive Charging

Supercapacitors based on 1T-molybdenum disulfide (MoS2) have achieved record high volumetric capacitance due to a combination of high surface area, bulk density and the ability for ions to easily penetrate between restacked layers. While many promising MoS2-based devices have been demonstrated, few works have examined capacitive charging mechanisms at the MoS2/electrolyte interface and how defects and oxidation play a role. In fact, unlike similar materials like graphene and graphite, no fundamental studies on double-charging have ever been reported for this promising material. In this talk, I will first discuss recent work from my group which examines degradation mechanisms which act to rapidly and significantly oxidize MoS2 during aqueous processing. Light, oxygen and pH are found to play significant roles in the degradation mechanism and rate. In the second part of my talk, I will describe a model study of charging mechanisms at flat electrodes composed of various ratios of 2H and 1T MoS2 produced by chemical exfoliation and with various degrees of oxidation. Using this system we attempt to identify the intrinsic capacitance of the 1T and 2H phase, the mechanism of charging and the impact of defects and oxidation on double-layer charging and pseudocapacitance and relate these to the known theories of charging at the interface of semi-metals and semi-conductors. The intrinsic capacitance and theoretical surface area are used to discuss theoretical capacitance limits for MoS2 and MoS2-based heterostructures.

Optoelectronic Properties of MoS2/g-ZnO van der Waals Heterostructure Investigated by First-Principles Calculations

The structural and optoelectronic properties of a MoS2-based heterostructure with a MoS2 monolayer stacked on a ZnO monolayer (g-ZnO) are calculated by first-principle simulations. MoS2/g-ZnO is a typical type II, indirect-bandgap van der Waals heterostructure. With the coupling interaction in the MoS2/g-ZnO heterostructure, the bandgap reduces with respect to both individual sheets, resulting in broadening of the absorption edges towards visible and near-infrared regions. For application in water splitting, the energy levels of the conduction-band minimum and valence-band maximum of the heterostructure are respectively high enough for water reduction and low enough for water oxidation, making this a promising functional material. For the MoS2 monolayer, the photocatalyst efficiency is limited by the high recombination rate of photogenerated electron–hole pairs. On the contrary, for the MoS2/g-ZnO van der Waals heterostructure, a large built-in electric field is formed at the interface, effectively facilitating separation of photogenerated electron–hole pairs and promoting its photocatalytic efficiency. This indicates that such MoS2/g-ZnO van der Waals heterostructures possess great prospects for application in photocatalytic and photovoltaic devices.

Strong interactions in molybdenum disulfide heterostructures boosting the catalytic performance of water splitting: A short review

Two-dimensional materials (2DMs) have attracted substantial attention due to their abundant active sites and their ultrahigh surface area for different catalytic applications due to the high lateral-longitudinal ratio. Transition metal dichalcogenides (TMDs), especially MoS2, as one of the 2DMs most often studied, have shown superior activity in electrochemical applications. Recently, combinations of different 2DMs have been widely studied, and they appear to be the most promising strategy available to develop state of the art catalysts for different reactions. In this article, we review the interactions between MoS2 and other materials as well as the novel assembly induced phase transitions of TMDs and their underlying mechanisms. Several methods for inducing the phase transition of TMDs by building MoS2-based heterostructures have been introduced. The electronic coupling between these counterparts has significantly enhanced their conductivity and optimized the energy states of the materials, thus introducing enhanced activity as compared to their original counterparts. The ideas summarized in this article may shed new light on and help to develop next-generation green energy materials by designing and constructing highly active two-dimensional catalysts for efficient water splitting.

Improving compactness and reaction kinetics of MoS2@C anodes by introducing Fe9S10 core for superior volumetric sodium/potassium storage

Molybdenum disulfides (MoS2) are presently attracting immense research interest as high gravimetric capacity anode materials in next-generation electrochemical batteries. However, achieving outstanding rate capability with high volumetric capacity in a single electrode remains highly challenging. Here, MoS2-based heterostructure materials including a conductive Fe9S10 core and carbon coating (Fe9S10@MoS2@C) are developed with a dense spatial geometry architecture and demonstrated as an advanced anode for simultaneously achieving high volumetric capacity and enhanced the reaction kinetics in both sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). The introduced Fe9S10 core plays crucial roles in significantly improving the electronic conductivity, facilitating the densifying of MoS2 particles, and constructing abundant heterogeneous interfaces with a strong electric field. Experimental studies and density functional theory calculation reveal that the formed heterointerfaces help to improve fast charging capability and cycle stability by decreasing the ion diffusion energy barrier and reinforcing geometry architecture. As a result, the Fe9S10@MoS2@C anode delivers a high volumetric capacity of 662 mAh cm−3, stable cycling performance (a capacity retention of 93.4% for 1000 cycles) and outstanding rate capability (high gravimetric capacities of 197 and 132 mA h g−1 at a large current densities of 30 and 50 A g−1, respectively) for SIBs, meanwhile, a high volumetric capacity of 408 mAh cm−3 with 95.4% capacity retention is achieved after 50 cycles for PIBs. The present work could guide the future designing protocol of heterostructure architectures by integrating suitable components for potential applications as high-performance alkali ion batteries electrode.

Investigation on photocatalytic mechanism of graphitic SiC (g-SiC)/MoS2 van der Waals heterostructured photocatalysts for overall water splitting.

Two-dimensional MoS2-based heterostructures have been given great attention due to their excellent properties. In this work, using first-principles calculations, the photocatalytic performances for overall water splitting and the photocatalytic mechanism of graphitic SiC (g-SiC)/MoS2 van der Waals heterostructures (vdWHs) have been deeply studied compared with the previous report. We align common type-II band edges for the g-SiC/MoS2 vdWH in different configurations, which demonstrates that the reduction and oxidation reactions are conducted on different parts in the g-SiC/MoS2 vdWHs. Besides, the built-in electric field induced by the charge transfer at the interface region can be used to hinder photogenerated e-/h+ from recombining, which is advantageous to the availably enhanced carrier mobility and extended lifetimes. More meaningfully, the g-SiC/MoS2 vdWHs all have considerable optical absorption as high as 105 cm-1 in the visible zone and enhanced absorption capacity in contrast to the separate g-SiC and MoS2 monolayers. Furthermore, owing to the contribution of built-in electric field, the g-SiC/MoS2 vdWH in diverse patterns can be used as an outstanding photocatalyst even under near-infrared light with high efficiency. Overall, these findings predict a promising application prospective for the g-SiC/MoS2 vdWHs as extraordinary photocatalysts for overall water splitting reactions, suggesting the valuable significance in the fields of hydrogen production and energy conversion.

Simultaneous dispersive and covalent monolayer MoS2/TiO2 cluster heterostructures: Insights into their enhanced photocatalytic activity

Tuning electron transfer at interface, largely depending upon interfacial interaction, is paramount to rationally designing nanoscale heterostructures with desirable performance for future electronics, optoelectronics, and solar energy conversion. Here, we explore the interfacial interaction between monolayer MoS2 and TiO2 cluster to elucidate the mechanism of the enhanced photocatalytic activity of their hybrids. It is firstly revealed that both dispersive (van der Waals forces) and covalent interactions can simultaneously exist in the monolayer MoS2/TiO2 cluster heterostructures, which depends on their relative orientations. The Ti-S and O=S bonds in covalently bonded heterostructures and flat bands in noncovalent heterostructures lead to an effective separation of photoexcited charge carriers between two constituents, therefore enhanced photocatalytic activity. The small band gap enables the MoS2/TiO2 cluster heterostructures having strong optical absorption in the whole visible light. Moreover, the Mo and S atoms at basal plane, which are catalytically inert, turn into catalytic active sites, making the monolayer MoS2 to be a highly active co-catalyst. These findings disclose the elusive microscopic mechanism behind the enhanced photocatalytic activity of MoS2/TiO2 hybrids, and provide a systematic step towards a better understanding of interfacial interaction in layered MoS2-based heterostructures.

Synthesis, properties, and optoelectronic applications of two-dimensional MoS2 and MoS2-based heterostructures.

As a two-dimensional (2D) material, molybdenum disulfide (MoS2) exhibits unique electronic and optical properties useful for a variety of optoelectronic applications including light harvesting. In this article, we review recent progress in the synthesis, properties and applications of MoS2 and related heterostructures. Heterostructured materials are developed to add more functionality or flexibility compared to single component materials. Our focus is on their novel properties and functionalities as well as emerging applications, especially in the areas of light energy harvesting or conversion. We highlight the correlation between structural properties and other properties including electronic, optical, and dynamic. Whenever appropriate, we also try to provide fundamental insight gained from experimental as well as theoretical studies. Finally, we discuss some current challenges and opportunities in technological applications of MoS2.

Basal-Plane Ligand Functionalization on Semiconducting 2H-MoS2 Monolayers.

Molybdenum disulfide (MoS2) is a two-dimensional material promising for electronic, optical, and catalytic applications. To fully harness its potential, functionalization is essential to controlling its properties. However, MoS2 functionalization has been mostly limited to either 1T-phase MoS2 or the edges of 2H-phase MoS2, and the chemistry of covalent functionalization on the basal plane of 2H-MoS2 is poorly understood. Here, we report a facile approach to covalently functionalize chemical vapor deposition (CVD) grown 2H-MoS2 monolayers (MLs), as well as mechanically exfoliated MoS2, via thiol conjugation at sulfur vacancies on the basal plane. Thorough characterization confirmed the functionalization by thiol molecules on MoS2 MLs, and we experimentally proved that sulfur vacancies in MoS2 MLs play a key role in the functionalization of basal planes. By the controlling of the amount of sulfur vacancies via sulfur annealing, the degree of MoS2 functionalization was effectively tuned. Because thiol conjugation partially repairs or passivates sulfur vacancies, enhanced photoluminescence response and decreased active sites for hydrogen evolution catalysis were observed for functionalized MoS2. Moreover, such functionalization can be utilized for making MoS2-based heterostructures, an example of which was demonstrated using a dithiol molecule to link MoS2 layers and PbSe quantum dots. These results provide new understanding and insights on the surface chemistry of MoS2 and open up more opportunities for MoS2 MLs with well-controlled properties and broader applications.

Multimodal Nonlinear Optical Imaging of MoS₂ and MoS₂-Based van der Waals Heterostructures.

van der Waals layered structures, notably the transitional metal dichalcogenides (TMDs) and TMD-based heterostructures, have recently attracted immense interest due to their unique physical properties and potential applications in electronics, optoelectronics, and energy harvesting. Despite the recent progress, it is still a challenge to perform comprehensive characterizations of critical properties of these layered structures, including crystal structures, chemical dynamics, and interlayer coupling, using a single characterization platform. In this study, we successfully developed a multimodal nonlinear optical imaging method to characterize these critical properties of molybdenum disulfide (MoS2) and MoS2-based heterostructures. Our results demonstrate that MoS2 layers exhibit strong four-wave mixing (FWM), sum-frequency generation (SFG), and second-harmonic generation (SHG) nonlinear optical characteristics. We believe this is the first observation of FWM and SFG from TMD layers. All three kinds of optical nonlinearities are sensitive to layer numbers, crystal orientation, and interlayer coupling. The combined and simultaneous SHG/SFG-FWM imaging not only is capable of rapid evaluation of crystal quality and precise determination of odd-even layers but also provides in situ monitoring of the chemical dynamics of thermal oxidation in MoS2 and interlayer coupling in MoS2-graphene heterostructures. This method has the advantages of versatility, high fidelity, easy operation, and fast imaging, enabling comprehensive characterization of van der Waals layered structures for fundamental research and practical applications.

Direct Growth of MoS₂/h-BN Heterostructures via a Sulfide-Resistant Alloy.

Improved properties arise in transition metal dichalcogenide (TMDC) materials when they are stacked onto insulating hexagonal boron nitride (h-BN). Therefore, the scalable fabrication of TMDCs/h-BN heterostructures by direct chemical vapor deposition (CVD) growth is highly desirable. Unfortunately, to achieve this experimentally is challenging. Ideal substrates for h-BN growth, such as Ni, become sulfides during the synthesis process. This leads to the decomposition of the pregrown h-BN film, and thus no TMDCs/h-BN heterostructure forms. Here, we report a thoroughly direct CVD approach to obtain TMDCs/h-BN vertical heterostructures without any intermediate transfer steps. This is attributed to the use of a nickel-based alloy with excellent sulfide-resistant properties and a high catalytic activity for h-BN growth. The strategy enables the direct growth of single-crystal MoS2 grains of up to 200 μm(2) on h-BN, which is approximately 1 order of magnitude larger than that in previous reports. The direct band gap of our grown single-layer MoS2 on h-BN is 1.85 eV, which is quite close to that for free-standing exfoliated equivalents. This strategy is not limited to MoS2-based heterostructures and so allows the fabrication of a variety of TMDCs/h-BN heterostructures, suggesting the technique has promise for nanoelectronics and optoelectronic applications.