Variations In Surface Morphology Research Articles

Dependence of Plant Uptake and Diffusion of Polycyclic Aromatic Hydrocarbons on the Leaf Surface Morphology and Micro-structures of Cuticular Waxes

The uptake of organic chemicals by plants is considered of great significance as it impacts their environmental transport and fate and threatens crop growth and food safety. Herein, the dependence of the uptake, penetration, and distribution of sixteen polycyclic aromatic hydrocarbons (PAHs) on the morphology and micro-structures of cuticular waxes on leaf surfaces was investigated. Plant surface morphologies and wax micro-structures were examined by scanning emission microscopy, and hydrophobicities of plant surfaces were monitored through contact angle measurements. PAHs in the cuticles and inner tissues were distinguished by sequential extraction, and the cuticle was verified to be the dominant reservoir for the accumulation of lipophilic pollutants. The interspecies differences in PAH concentrations cannot be explained by normalizing them to the plant lipid content. PAHs in the inner tissues became concentrated with the increase of tissue lipid content, while a generally negative correlation between the PAH concentration in cuticles and the epicuticular wax content was found. PAHs on the adaxial and abaxial sides of a leaf were differentiated for the first time, and the divergence between these two sides can be ascribed to the variations in surface morphologies. The role of leaf lipids was redefined and differentiated.

Deposition rate dependant formation and properties of Sn2S3 and SnS thin films by co-evaporation

We report the effect of deposition rate on the formation and properties of tin sulfide (Sn2S3 and SnS) thin films prepared by co-evaporation technique. The structural, morphological and optical properties of these films have been investigated as the function of deposition rate. X-ray photoelectron spectroscopy analysis confirmed the transformation of Sn2S3 phase to SnS phase with the increase in deposition rate of tin. The structural analysis by XRD and Raman showed the formation of Sn2S3 and SnS phases. The variation in surface morphology and roughness of the as- deposited films have been examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). UV–Vis–NIR spectrometer was employed to record the transmission spectra of the samples in the wavelength range of 200–3000 nm. Film thickness (d), optical band gap (Eg), refractive index (n) and extinction coefficient (k) of the deposited thin films are estimated from the optical data. Photo conductivity of the as-deposited films has been studied using two probe method. Hall effect measurements show an n-type to p-type conversion in electrical conductivity with increase in deposition rate.

Electric field induced slanting growth of silicon nanowires with enhanced hydrophobic property

The etching process of Si nanowires under DC electric field was studied in this work. Interestingly, the growth direction of silicon nanowires became slanting when applied with DC electric intensity of 600V/m, which greatly influenced the surface wettability ascribed to the variation of surface morphologies. The contact angle of slant Si nanowire was enhanced compared with vertical growth Si nanowire (132.4° vs. 86.8°).

Influence of O2 pressure on structural, morphological and optical properties of TiO2-SiO2 composite thin films prepared by pulsed laser deposition

In this work, TiO2-SiO2 composite films were grown on amorphous quartz substrate at different oxygen partial pressure by pulsed laser deposition technique. The influence of oxygen partial pressure on structural, optical and surface properties of films was examined. Grazing incidence X-ray diffraction showed the formation of TiO2 rutile phase and degree of crystallinity decreased with the increase of oxygen pressure. Energy band gap of the films increased from 3.3 to 3.6 eV with the increase of oxygen pressure from 13.33×10−3Pa to 20.00Pa. Variation of surface morphology of films with increasing oxygen partial pressure was studied by Atomic Force Microscopy (AFM). AFM images are showing that grain size of deposited films is increasing with increasing oxygen pressure. Field effect scanning electron microscopy images also shows the similar surface morphology. X-ray Photoelectron Spectroscopy shows the evidence of oxygen defect and related Ti3+ states in composite films. Composite films showed blue photoluminescence (PL) emission by the excitation of 350nm wavelength. Deconvoluted PL peaks showed emission originated from Ti3+ defect level associated with an oxygen vacancy. Oxygen vacancy decreased with increasing oxygen pressure. Intense blue emission with high luminous efficacy of radiation and maximum flux was achieved for 13.33×10−3Pa oxygen pressure. Deposited films might be used in the field of blue light emitting diode application.

Effects of anodization parameters on the corrosion resistance of 6061 Al alloy using the Taguchi method

Anodizing 6061 aluminum alloy (AA6061) in a H2SO4 electrolyte solution is a crucial process in the formation of anodic aluminum oxide (AAO) film for enhancing the material’s corrosion resistance. In this work, the effects of electrolyte concentration, current density, and anodization time parameters on the evolution of corrosion resistance in AA6061 alloy were investigated using the Taguchi method. Each anodization parameter had three levels using an experimental set of L9 orthogonal arrays. Variation in the bias voltage was recorded during the AAO process, and an energy-dispersive spectrometer was used to analyze the variations in the composition of the oxidized films. Variations in surface morphology and cross-sections of the AAO were examined using a scanning electron microscope. Finally, the potentiostatic polarization method was used to judge the relative corrosion resistance of the oxidized films. The oxidized film with the best corrosion resistance (Icorr = 8.516 × 10−11 A/cm2) was obtained by anodizing at a current density of 1 A/dm2 in 1 M sulfuric acid for 20 min.

Modeling the wear process of the ring/liner conjunction considering the evaluation of asperity height distribution

This paper presents a combined mixed lubrication and wear model to study the running-in process of the ring/liner system. In this model, the elastic-plastic asperity deformation is considered, as well as the evolution of asperity height distribution due to the asperity plastic deformation and wear. Meanwhile, the wear is computed with the Archard’s wear law based on the asperity contact load. In this way, variations of friction loss, wear depth and surface morphology are obtained for the whole rubbing process. It is found that in the initial stage of running-in process, the effect of the asperity height distribution induced by asperity plastic deformation on the mixed lubrication performance is significant and even exceeds the contribution of wear.

Evaluation of Cr(VI) reduction mechanism and removal by Cellulosimicrobium funkei strain AR8, a novel haloalkaliphilic bacterium

The present study, a novel haloalkaliphilic Cr(VI) tolerant bacterial strain, Cellulosimicrobium funkei AR8, was isolated and characterized for its high Cr(VI) reduction. In batch experiments, Cr(VI) reduction was evaluated under different parametric conditions which include different pH (5–9), temperature (25–45°C), NaCl (0–3%) and Cr(VI) concentrations (100–250μg/ml). Variations in the cell surface functional groups and morphology of the bacterial cells after Cr(VI) reduction were characterized by FT-IR and SEM–EDX. FT–IR analysis revealed that cell surface functional groups such as alkanes, amide and amines are involved in chromium biosorption and SEM–EDX results showed that biosorption and immobilization of chromium species on the cell surface. Bioconversion of Cr(VI) into Cr(III) by strain AR8 was confirmed by XRD and Raman spectroscopy analysis. Intracellular localization of reduced product (Cr(III)) was visualized by TEM analysis. Various instrumentation analysis verified that Cr(VI) removal mechanism of C. funkei AR8 strain was achieved by both extra and intracellular reducing machinery. Toxicity study revealed that the bacterially reduced product exerted less toxic effects on phenotypic, survival (91.31%), hatching (84.04%) and heart function (115±1.03 beats/min) of zebrafish (Danio rerio) embryos. Higher Cr(VI) reducing ability of the strain under haloalkaliphilic condition suggests the C. funkei AR8 as a novel and efficient strain for remediating Cr(VI) contaminated industrial effluents with high salinity and alkalinity.

Characterization of Alkali-Induced Quartz Dissolution Rates and Morphologies

A number of studies have investigated the impact of alkali cations on quartz dissolution to increase the understanding of natural rock weathering and enhance the predictability of silica behaviour in reservoir systems. However, there are few evidences for how alkali cations approach the quartz surface. Thus, this study is an attempt to provide empirical evidence on the interaction of electrolytes (\(\hbox {Na}^{+}, \hbox {K}^{+}, \hbox {Ca}^{2+})\) with quartz surface. Bulk quartz grains and clean-faced single quartz crystals were dissolved/etched in varying pH solutions of acidic, near-neutral/neutral and alkali solutions (KOH, NaOH, KCl, NaCl, \(\hbox {CaCl}_{2}, \hbox {CH}_{3}\hbox {COOH}\), HCl). The amount of dissolved silica was measured with molybdate spectrophotometry method, while variations in quartz surface morphology were studied using scanning electron microscopy attached with EDX. Quartz dissolution rates varied with pH, hydrated radius and hydrolysis constants of alkali cations in the order: \(\hbox {Ca}^{2+}<\hbox {Na}^{+}<\hbox {K}^{+}\). Relatively deeper triangular etch pits were observed in quartz dissolved in KOH and NaOH solutions, while shallower pits formed in neutral solutions, and exsolution faces and lamellae were formed in quartz dissolved in low-pH solutions. The results also showed that interfacial secondary phases of cationic silicates play a key role in quartz dissolution.

Influence of overlapped sustain waveform on panel-aging characteristics based on MgO surface morphology variation in alternating-current plasma display panel

ABSTRACTThis paper has been investigated the changes in the discharge characteristics and surface morphology of the MgO surface on both the indium thin oxide (ITO) and bus electrodes when the conventional (non-overlapped) and overlapped sustain waveforms are applied during the panel-aging process in alternating-current plasma display panel. For conventional sustain waveform, the strong surface discharge is confined within the ITO electrode, whereas for overlapped sustain waveform, the strong surface discharge is produced and spread toward the end of the bus electrode as well as the ITO electrode. It is demonstrated that the overlapped sustain waveform is a very effective aging waveform that can obtain the uniform surface morphology of the MgO thin film on both the ITO and bus electrodes.

Flexible-Blade Coating of Small Molecule Organic Semiconductor for Low Voltage Organic Field Effect Transistor

A flexible-blade coating (FBC) approach, using a simple thin and flexible steel sheet as the meniscus guide, is developed to deposit the blended small molecule organic semiconductor (OSC) solution on substrate surface with pre-fabricated electrode patterns. During coating, the bottom edge of the used flexible steel film touches the substrate surface, but can bend up adapting to the surface morphology variation without causing any damages to the bottom electrodes. With this approach, little amount of very dilute ink solution can be used to coat the channel film, resulting in the greatest material saving among all reported methods. It is shown that, by using the FBC at a moving speed of 12 mm/s to deposit the OSC layer, all solution processed low-voltage organic field effect transistor composed of another polymer gate dielectric layer and inkjet printed metal electrodes were achieved over relatively large area with high performance and good uniformity.

Prediction of Interfacial Surface Energy and Effective Fracture Energy From Contaminant Concentration in Polymer-Based Interfaces

The principals of interfacial fracture mechanics and modified Gibbs adsorption equation are utilized to provide a predictive correlation for the macroscopic (effective) fracture toughness of polymer-based adhesive interfaces, exposed to varying level of contaminant concentration. The macroscopic fracture toughness measurement by double cantilever beam test exhibits a progressive deterioration with the increase of the contaminant surface concentration. The associated variation of fracture surface morphology exhibits ductile-to-brittle failure transition, caused by the contamination-induced suppression of plastic deformation within the adhesive layer. The corresponding intrinsic interfacial surface energy is extracted by finite-element simulation, employing surface-based cohesive elements. The modified Gibbs adsorption equation is utilized to correlate the contamination-induced degradation of the interfacial surface energy as a function of contaminant surface concentration. Interfacial fracture mechanics principals are applied to extend the correlation to the macroscopic fracture toughness of the interface. With additional examination of other systems, the proposed correlation may provide the basis for nondestructive evaluation of bond line integrity, exposed to different levels of contaminant.

Study of variation in surface morphology, chemical composition, crystallinity and hardness of laser irradiated silver in dry and wet environments

Variation in surface morphology, chemical composition, crystallinity and hardness of laser irradiated silver in dry and wet ambient environments has been investigated. For this purpose, the silver targets were exposed for various number of laser pulses in ambient environment of air, ethanol and de-ionized water for various number of laser pulses i.e. 500, 1000, 1500 and 2000. Scanning Electron Microscope (SEM) was employed to investigate the surface morphology of irradiated silver. SEM analysis reveals significant surface variations for both dry and wet ambient environments. For lower number of pulses, in air environment significant mass removal is observed but in case of ethanol no significant change in surface morphology is observed. In case of de-ionized water small sized cavities are observed with formation of protrusions with spherical top ends. For higher number of laser pulses, refilling of cavities by shock liquefied material, globules and protrusions are observed in case of dry ablation. For ablation in ethanol porous and coarse periodic ripples are observed whereas, for de-ionized water increasing density of protrusions is observed for higher number of pulses. EDS analysis exhibits the variation in chemical composition along with an enhanced diffusion of oxygen under both ambient conditions. The crystal structure of the exposed targets were explored by X-ray Diffraction (XRD) technique. XRD results support the EDS results. Formation of Ag2O in case of air and ethanol whereas, Ag2O and Ag3O in case of de-ionized water confirms the diffusion of oxygen into the silver surface after irradiation. Vickers Hardness tester was employed to measure the hardness of laser treated targets. Enhanced hardness is observed after irradiation in both dry and wet ambient environments. Initial decrease and then increase in hardness is observed with increase in number of laser pulses in air environment. In case of ethanol, increase in number of laser pulses results in continuous decrease in hardness. Whereas, in case of de-ionized water hardness increases with increase in number of laser pulses.

Incorporation of Copper Enhances the Anti-Ageing Property of Flame-Sprayed High-Density Polyethylene Coatings

High-density polyethylene (HDPE)-copper (Cu) composite coatings were prepared through depositing HDPE-Cu core-shell particles by flame spraying. The HDPE-Cu composite coatings and the HDPE coatings were aged in xenon lamp ageing testing chamber. The variations of chemical compositions and surface morphology of the coatings before and after the ageing testing were analyzed using infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry and ultraviolet-visible spectrophotometer. Results show that there is no chemical composition variation in the HDPE-Cu coatings. Cracks were found on the surfaces of the HDPE coatings, while the HDPE-Cu coating shows almost intact surface morphology. These results suggest that the HDPE-Cu coatings present better anti-ageing performances than the HDPE coatings. Further assessment of the function of Cu shells on the anti-ageing property reveals that Cu shells not only enhanced the absorption of the coatings to ultraviolet, but also increased their reflectivity to visible light. Additionally, the Cu shells enhanced the decomposition temperature and thermal stability of HDPE in the composite coatings. These results give bright insight into potential anti-ageing applications of the polymer-based structures.

Wettability assessment of plasma-treated PBO fibers based on thermogravimetric analysis

Changes in the surface wettability of poly(p-phenylene benzobisoxazole) (PBO) fibers were investigated by thermogravimetric analysis (TGA) following an air dielectric barrier discharge (DBD) plasma treatment. The results were then supplemented and confirmed by scanning electron microscopy (SEM), dynamic contact angle analysis (DCAA), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) measurements. After exposure to the DBD plasma at a pre-determined power level, TGA analysis showed that the residual rates retained by the PBO composites decreased, which meant an increase in the amount of resin coating the PBO fibers in the composites. Observations by SEM confirmed that there was more resin adhering to the treated PBO fibers and the wetting behavior of resin on the fibers was greatly improved. Meanwhile, DCAA for the treated fibers showed a significant enhancement in fiber surface free energy. XPS and AFM were performed in order to reveal any variations in fiber surface activity and surface morphology resulting from the surface treatment. The resulting data showed that increases in oxygen-containing polar groups and surface roughness on the plasma-treated PBO fibers contributed to the above improved wetting behavior. With comprehensive analyses, it was concluded that TGA could be used as a supporting method assessing the surface wettability of PBO fibers before and after air DBD plasma treatment.

Fractal and pore dispositions of coal seams with significance to coalbed methane plays of East Bokaro, Jharkhand, India

In India, much attention has been paid to the Gondwana coals of Permian age of Damodar valley, which comprises the major CBM producing blocks. East Bokaro Coalfield is part of Damodar valley and one of the promising potential CBM plays. In this study, the technological properties, TOC content, thermal maturity (Ro%), low pressure N2 sorption isotherm and SEM analyses were performed to find out the significance of fractal dimension, pore dispositions and associated geological influence on pore structure and fractal dimensions for better understanding of gas adsorption capacities of coal seams of East Bokaro. The micropore and mesopore specific surface area obtained through DR and multi-point BET ranges from 0.18 to 8.86 m2/g and 0.42–7.41 m2/g respectively, signifying dominance of micro and mesopores involvement in specific surface area. The BJH and DFT pore volume varying from 0.002 to 0.007 and 0.001–0.007 cc/g respectively. It is observed that the considerable pore volume contributed by mesopores of the range 3–50 nm and least fractions of macropores ranges from 50 to 278 nm. There is a tremendous increase in pore volume, when the pore size in between 4 and 16 nm, these pores are particularly more suitable for gas storage and associated with carbon rich vitrinite maceral. The pore size distribution obtained through BJH, DFT, DA, DR and average pore diameter values ranges from 2.99 to 10.20, 1.77–3.17, 1.42–2.48, 0.46–3.28 and 4.48–16.43 nm respectively. The opening of the hysteresis loop at lower pressure ∼0.2 (P/P0) and closing of hysteresis loop between 0.6 and 0.8 (P/P0) acutely connects to the adsorption branch is revealing of cavitation and irregularities in pore structures, consequently rapid decline in desorption curve due to the condensation and evaporation characteristics of micro and mesopores, often associated with combined slit and bottle neck pores and bottle-neck open ended shaped mesopores. The variations in correlation coefficients of two separate linear segments of fractal dimensions (D1 and D2), summarizes the suitability of D1, for pore structure analysis. Nevertheless, the low values of fractal dimensions (D1 = 1.1600–2.5450 and D2 = 1.5580–2.8730), signifies the pore surfaces are controlled by heterogeneity of coal composition. However, the correlations of D2 with ash, average pore diameter, specific surface area, Ro%, pore volume and depth accentuated that D2 may be considered for CBM reservoir characterization of East Bokaro Coalfield. The very good correlations between depth with D2, total pore volume and thermal maturity (Ro%) signifies the intensification of fractal dimensions as a function of reduction and variations in pore diameter with increasing degree of coalification. The effects of rank upon fractal dimensions are mainly due to structured variety of micropore and mesopore of coals. SEM studies supports the variations in surface morphology, pore structure and fractal dimension controlled by complex coal compositional parameters like carbon content, volatile matter, thermal maturity and pore size distribution.

Oxygen partial pressure induced effects on the microstructure and the luminescence properties of pulsed laser deposited TiO2 thin films

In this work, the influence of oxygen partial pressure on structural, morphological, and optical properties of TiO2 thin films grown on fused quartz substrate at different oxygen partial pressure by pulsed laser deposition were examined. X-Ray diffraction (XRD) patterns show the formation of TiO2 anatase phase deposited at high oxygen pressure. Atomic Force Microscopy (AFM) reveals that surface roughness of the films increases with oxygen pressure. Variation of surface morphology of films with increasing oxygen partial pressure was studied by AFM. It is observed that energy band gap of the films increases from 3.27 eV to 3.52 eV with the increase of oxygen pressure and is attributed to the decrease of oxygen defects. TiO2 thin films exhibited blue emission under the excitation of 320 nm wavelength. De-convoluted photoluminescence (PL) peaks showed that defect states are responsible for visible emission in TiO2 thin films. The intensity of PL emission associated with oxygen vacancies decreases with increasing oxygen pressure. Photometric characteristic analysis shows that the films deposited 1x10-4 mbar oxygen pressure exhibited intense blue emission with high luminescence efficacy of radiation.

Estimation of Heat Transfer Coefficients for Biomass Particles by Direct Numerical Simulation Using Microstructured Particle Models in the Laminar Regime

Direct numerical simulation of convective heat transfer from hot gas to isolated biomass particle models with realistic morphology and explicit microstructure was performed over a range of conditions in the laminar regime. Steady-state results demonstrated that convective interfacial heat transfer is dependent on the wood species. The computed heat transfer coefficients were shown to vary between the pine and aspen models by nearly 20%. These differences are attributed to the species-specific variations in the exterior surface morphology of the biomass particles. We also quantify variations in heat transfer experienced by the particle when positioned in different orientations with respect to the direction of fluid flow. These results are compared to previously reported heat transfer coefficient correlations in the range of 0.1 < Pr < 1.5 and 10 < Re < 500. Comparison of these simulation results to correlations commonly used in the literature (Gunn, Ranz–Marshall, and Bird–Stewart–Lightfoot) shows that the...

Topography evolution and friction coefficient of gray and nodular cast irons with duplex plasma nitrided + DLC coating

In the present study, the main critical factors affecting the production of high tribological performance coatings on substrates containing near surface graphite were evaluated. Plasma nitriding followed by deposition of a hydrogenated diamond like carbon film (a-C:H) on gray cast iron (GCI) and nodular cast iron (NCI) substrates were carried out using a single thermal cycle. The surface topography evolution was evaluated via Scanning Electron Microscopy (SEM) and White Light Interferometry (WLI). As expected, there is a huge variation in surface topography and morphology according to graphite shape. An intense modification on the topography of GCI was observed, in particular wedges formation after nitriding. In order to enable a more in-depth understanding, the surface evolution after plasma nitriding of cast irons was carefully investigated and discussed in light of EDS linescans and XRD. Micro Raman spectroscopy and TEM analysis indicated that the DLC has an average amount of clustered sp2 bonding in the structure. Additionally, the tribological performance of multifunctional coatings was evaluated via durability tests in ambient air, which revealed friction coefficients as low as 0.06 during steady-state lubrication regime for gray cast iron substrates, whereas the values were of 0.14 for nodular cast iron substrates. Crucial differences were found between friction coefficient behaviours: the GCI presented lubricious tribolayers covering most part of wear track whereas NCI presented topographic factors inhibiting tribolayers formation, a key factor that might explain the friction coefficient variation.

Enhancing Long-Range Ordering of P3HT by Incorporating Thermotropic Biphenyl Mesogens via ATRP

The methoxybiphenyl liquid crystalline mesogen 6-((4′-methoxy-[1,1′-biphenyl]-4-yl)oxy)hexyl methacrylate (MeOBP) was incorporated into block copolymers with regioregular poly(3-hexylthiophene) (P3HT) by a combination of Grignard metathesis (GRIM) and atom transfer radical polymerization (ATRP) techniques. Side chain engineering with a thermotropic liquid crystalline segment produced an improved morphology resulting in field-effect mobilities of ∼10–2 cm2/(V s) measured in organic thin film transistors (OTFTs). It was observed that improved π–π stacking distances between edge-on oriented polythiophene segments upon annealing facilitated charge transport which was accomplished with π–π stacked biphenyl mesogens with P3HT block. Variation of surface morphology of polymer thin films upon annealing was investigated by tapping mode atomic force microscopy (TMAFM). A combined study of differential scanning calorimetry (DSC) and polarized optical microscopy (POM) was also performed to identify liquid crystalline...

Synthesis of MoS2 on Homogeneous Single Layer Epitaxial Graphene on 6H-SiC(0001)

Molybdenum Disulfide (MoS2 ) is a semiconducting transition metal dichalcogenide (TMD) formed when Mo is sandwiched between S atoms to form either a trigonal prismatic or octahedral atomic structure. Theoretical studies using different first principles calculations show exceptional optical band structure dependence on layer thickness, a property that makes the nanomaterial system a promising candidate for high performance, low cost tunable materials for flexible electronics, high electron mobility transistors and field tunneling transistors. The 2D heterostructure materials reported in the literature have been primarily investigated from sub-micron size flakes produced by mechanical exfoliation process followed by transfer onto SiO2/Si substrate. This technique is only useful for laboratory-based, proof-of-concept studies that cannot be scaled for industrial production. In addition, device structures fabricated from flakes are known to have interface impurities that degrade the device performance. It is therefore prudent that a direct approach for the formation of integrated 2D heterostructure with tunable properties be studied. This presentation will highlight synthesis of nucleation structures of MoS2 , effects of underlying Epitaxial Graphene (EG) layer on MoS2 lateral growth and corresponding optical as well as composition variation across the step-bunched terrace widths of the templated layers of EG/6H-SiC(0001). µ-Raman spectroscopy, AFM and Photoluminescence (PL) will be used to extract composition, presence, layer thickness, surface morphology variations and optical band structures of the heterostructure. The synthesis process of MoS2 on a template of monolayer EG/6H-SiC(0001) was carried out in horizontal CVD reactor at 800°C – 950˚C for 10 - 30 min in a flowing UHP Ar/H2 ambient of 80/20 sccm and 10 - 100 mbar. The initial Raman Spectroscopy characterization of MoS2/EG/6H-SiC heterostructure shows planar (E2) and axial (A1) acoustic active modes of underlying 6H-SiC at 250 and 501 wave numbers, respectively. In addition, the out-of-plane vibrations of S atoms (A1) and in-plane vibrational modes of Mo and S atoms (E1 1g) were located at 402 and 378 wave numbers, respectively (refer to Figure 1). The Raman spectrum also show EG Raman 2D mode post MoS2 synthesis, suggesting preservation of underlying EG. The successful synthesis of wafer-scale formation of MoS2 /EG/SiC heterostructures offers the opportunity for a number of applications with significant advantages over the conventional top-down exfoliation and transfer process. For instance, direct growth of MoS2 on n-type 6H-SiC(0001) eliminates the need to transfer the TMD to another substrate, consequently allowing no impurities to be pinned at the interfaces thereby mitigation against the short channel effects in device structures, enabling tunneling devices and variations of hot electron transistor devices. Figure 1