2H MoS2 Research Articles

Edge-enriched laminar hexagonal (2H) MoSe2-anchored sulfur vacancies-rich ReS2 nanoflowers for boosted light-to-hydrogen conversion

Developing innovative S-scheme photocatalytic systems with highly active catalysts are of huge interest in converting solar energy into hydrogen in a sustainable manner. Herein, sulfur vacancies (Sv)-rich hierarchical flower-like ReS2-hybridized laminar hexagonal (2H) MoSe2 (2H-MoSe2) were constructed for water splitting. Systematic studies show that interfacial chemical interaction of Mo–S bond and built-in electric field induce the S-scheme charge transfer mode, as verified by the generated superoxide radicals, band structures, and density functional theory calculation. With the intense cooperative effects of Mo–S bonds, S-vacancies, and internal electric field, the optimized Sv-ReS2/2H-MoSe2 heterojunction concurrently attains populated exposed active sites, superior electron-hole separation efficiency, and intensive affinity to reactant water molecules, achieving a maximum hydrogen production rate of 78.2 μmol/h with an apparent quantum yield of 9.3% at 420 nm, which is approximately 5.9-fold greater than pristine ReS2. This work paves a new avenue to engineering S-scheme catalysts for sustainable solar-to-fuel conversion.

Ex Situ Characterization of 1T/2H MoS2 and Their Carbon Composites for Energy Applications, a Review.

The growing interest in the development of next-generation net zero energy systems has led to the expansion of molybdenum disulfide (MoS2) research in this area. This activity has resulted in a wide range of manufacturing/synthesis methods, controllable morphologies, diverse carbonaceous composite structures, a multitude of applicable characterization techniques, and multiple energy applications for MoS2. To assess the literature trends, 37,347 MoS2 research articles from Web of Science were text scanned to classify articles according to energy application research and characterization techniques employed. Within the review, characterization techniques are grouped under the following categories: morphology, crystal structure, composition, and chemistry. The most common characterization techniques identified through text scanning are recommended as the base fingerprint for MoS2 samples. These include: scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Similarly, XPS and Raman spectroscopy are suggested for 2H or 1T MoS2 phase confirmation. We provide guidance on the collection and presentation of MoS2 characterization data. This includes how to effectively combine multiple characterization techniques, considering the sample area probed by each technique and their statistical significance, and the benefit of using reference samples. For ease of access for future experimental comparison, key numeric MoS2 characterization values are tabulated and major literature discrepancies or currently debated characterization disputes are highlighted.

Efficient Hydrogen Evolution via 1T-MoS2 /Chlorophyll-a Heterostructure: Way Toward Metal Free Green Catalyst.

Electrocatalytic hydrogen evolution reaction (HER) is regarded as a sustainable and green way for H2 generation, which faces a great challenge in designing highly active, stable electrocatalysts to replace the state-of-art noble metal-platinum catalysts. 1T MoS2 is highly promising in this regard, but the synthesis and stability of this is a particularly pressing task. Here, a phase engineering strategy has been proposed to achieve a stable, high-percentage (88%) 1T MoS2 /chlorophyll-a hetero-nanostructure, through a photo-induced donation of anti-bonding electrons from chlorophyll-a (CHL-a) highest occupied molecular orbital to 2H MoS2 lowest unoccupied molecular orbital. The resultant catalyst has abundant binding sites provided by the coordination of magnesium atom in the CHL-a macro-cycle, featuring higher binding strength and low Gibbs-free energy. This metal-free heterostructure exhibits excellent stability via band renormalization of Mo 4d orbital which creates the pseudogap-like structure by lifting the degeneracy of projected density of state with 4S in 1T MoS2 . It shows extremely low overpotential, toward the acidic HER (68 mV at the current density of 10mA cm-2 ), very close to the Pt/C catalyst (53mV). The high electrochemical-surface-area and electrochemical turnover frequency support enhanced active sites along with near zero Gibbs free energy. Such a surface-reconstruction strategy provides a new avenue toward the production of efficient non-noble-metal-catalysts for the HER with the aim of green-hydrogen production.

Multi-Interface polarization engineering constructed 1T-2H MoS2 QDs/Y-NaBi(MoO4)2 multiple heterostructure for high-efficient piezoelectric-photoelectrocatalysis PDE-5i degradation

The rational application of piezoelectric polarization properties in non-centrosymmetric heterojunctions to improve charge separation efficiency is a novel approach for enhancing their photoelectrocatalytic capabilities for environmental purification. Herein, a noval 1T-2H MoS2 QDs/Y-NaBi(MoO4)2 multiple heterostructures with two types S-scheme heterojunctions was formed by multi-functional materials NaBi(MoO4)2 with Y3+ ion-doping and multi-phase state (1T, 2H and 1T-2H) MoS2 quantum dots multi-interface polarization engineering. Material characterization and DFT calculations revealed that 1T-2H MoS2 QDs/Y-NaBi(MoO4)2 multiple heterostructures produce highly-efficient Bi-S-Mo(IV) and Mo(IV)-S-Mo(VI) charge-transfer channels induced by multi-interface polarization engineering. 1T-2H MoS2 QDs/Y-NaBi(MoO4)2 heterostructures were developed as photoanodes using the pressed tablet stainless-steel mesh (PT-SSM) method, and demonstrated conspicuous piezoelectric-photoelectrocatalytic (PZ-PEC) efficiency (99.88% removal within 40 min) for the degradation of organic pollutant phosphodiesterase-5 inhibitor (PDE-5i) under visible light illumination, direct-current external bias and mechanical force. This work provides new insight for synergy and mechanism between piezoelectric effect and photoelectrocatalysis for environmental clean-up.

Stable 1T –2H MoS2 heterostructures for efficient electrocatalytic hydrogen evolution

1T-phase molybdenum disulfide (1T MoS2) can efficiently facilitate the charge transfer and provide the active site, exhibiting a better hydrogen evolution reaction (HER) than 2H MoS2. However, its thermodynamic instability becomes a major drawback that hinders its practical application. We report a chemical vapor deposition (CVD) method to grow MoS2 nanosheets with high 1T content (61.5%) by introducing an appropriate amount of antimony oxide. The 1T-2H hybrid structures grown in this mode are thermodynamically stable. 1T phase of the MoS2 produces a unique charge distribution that makes the S atoms at the 1T-2H interface more favorable for H adsorption, thus enhancing the HER activity on the MoS2 basal plane. This study has provided a new idea for the 1T-phase MoS2 preparation for efficient HER.

Scalable synthesis of MoS2 nanosheets electrocatalyst towards high-efficiency nitrite reduction to ammonia

Ammonia is a vital chemical raw material for both industry and agriculture, the current ammonia synthesis process is based on the Haber-Bosch process yet faces issues of high-energy consumption and high CO2 emission. Electrochemical nitrite reduction reaction (NO2−RR) has been considered as one of the alternative paths for ammonia synthesis. Here, we develop a large-scale viable route for synthesis of 2H–MoS2 nanosheets (MoS2 NSs), which show high activity as electrocatalyst for high-efficiency conversion of NO2−RR to ammonia, the yields of NH3 production rate reaches as high as 8.99 mg cm−2 h−1 with a faradaic efficiency of 93.52%. A hybrid electrolytic cell is constructed by coupling MoS2 NSs as NO2−RR cathode in neutral electrolyte with oxygen evolution reaction (OER) in alkaline solution, which can operate stably for more than 120 h with the capability of continuously producing ammonia at the production rate of 38.79 mg cm−2 h−1.

Direct Evidence of the Role of Co or Pt, Co Single-Atom Promoters on the Performance of MoS2 Nanoclusters for the Hydrogen Evolution Reaction

Developing alternatives to platinum (Pt) and iridium (Ir) in proton-exchange membrane water electrolyzers is crucial on the way to viable energy provision schemes. However, although it seems difficult to substitute Ir, alternatives exist for Pt at the proton-exchange membrane water electrolyzer cathode. Here, we report on the synthesis and the characterization of efficient and durable hydrogen evolution reaction (HER) nanocatalysts based on MoS2 supported on high-surface-area carbon. Citric acid was used as a chelating agent to control the size of the MoS2 crystallites (1.4 nm) and thus the density of active sites (slab edges). Inspired by successful approaches in catalysis for hydrodesulfurization reactions, conventional 2H MoS2 was sequentially doped with cobalt (Co) and then with 1 wt % of Pt. Overpotentials of 188, 140, and 118 mV at 10 mA cm–2 are reported for MoS2/C, Co–MoS2/C, and Pt1%–CoMoS2/C, respectively. This result is attributed to the weakening of the Hads binding energy of the promoted MoS2-edge active sites (because the promoting atoms are mostly located at the edges). Associated with small-metal dissolution rates (monitored in situ, during the HER), our findings demonstrate that metal promotion (doping) is a promising route to replace Pt with earth-abundant elements in acidic water electrolyzers.

Massively synthesizable nickel-doped 1T-MoS2 nanosheet catalyst as an efficient tri-functional catalyst.

In this study, a nickel (Ni)-doped 1T-MoS2 catalyst, an efficient tri-functional hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) catalyst, was massively synthesized at high pressure (over 15 bar). The morphology, crystal structure, and chemical and optical properties of the Ni-doped 1T-MoS2 nanosheet catalyst were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and ring rotating disk electrodes (RRDE), and the OER/ORR properties were characterized using lithium-air cells. Our results confirmed that highly pure, uniform, monolayer Ni-doped 1T-MoS2 can be successfully prepared. The as-prepared catalysts exhibited excellent electrocatalytic activity for OER, HER, and ORR owing to the enhanced basal plane activity of Ni doping and formidable active edge sites resulting from the phase transition to a highly crystalline 1T structure from 2H and amorphous MoS2. Therefore, our study provides a massive and straightforward strategy to produce tri-functional catalysts.

Tunable biaxial strain device for low-dimensional materials.

Strain is attracting much interest as a mean to tune the properties of thin exfoliated two-dimensional materials and their heterostructures. Numerous devices to apply tunable uniaxial strain are proposed in the literature, but only few for biaxial strain, often with a trade-off between maximum strain and uniformity, reversibility, and device size. We present a compact device that allows for the controlled application of uniform in-plane biaxial strain, with maximum deformation and uniformity comparable to those found in much larger devices. Its performance and strain uniformity over the sample area are modeled using finite element analysis and demonstrated by measuring the response of exfoliated 2H-MoS2 to strain by Raman spectroscopy.

Organic interlayers boost the activity of MoS2 toward hydrogen evolution by maintaining high 1T/2H phase ratio

1T-MoS2 shows great promise for hydrogen production due to phenomenal performance in catalyzing hydrogen evolution reaction (HER) from water. However, this phase converts to low-active 2H–MoS2 on superambient heating. A series of MoS2 layered compounds (LCs) with guest organic cations was prepared to reveal the effect of cationic organics on the structure stabilization of 1T-MoS2 and thereby on the catalytic performance of this phase in HER. The results showed that LCs provide significantly higher 1T/2H ratio after heating than non-stabilized 1T phase and some of them exhibit excellent thermal durability in the capacity of HER catalysts. The effect is most pronounced for the organics remaining tightly bound to sulfide sheets in a sulfuric acid electrolyte. Cetyltrimethylammonium and bis(dimethylamino)naphthalene perfectly matched this criterion and provided a long-term maintaining of catalyst activity. The data obtained in this study are hoped to offer new approach for rational design of the efficient non-precious 1T-MoS2-based electrocatalysts for hydrogen production.

Potential and support-dependent hydrogen evolution reaction activation energies on sulfur vacancies of MoS2 from GC-DFT

We present a detailed mechanistic study of HER at the sulfur vacancy VS of 2H–MoS2. We evaluate the Volmer, Tafel, and Heyrovsky transition states for the different possible reaction steps, determining the activation energy as a function of the electrochemical potential via grand-canonical density functional theory. The results show that the Volmer and Heyrovsky steps depend on the electrochemical potential and the activation energies decrease for more negative potentials, while this is not the case for the Tafel step, for which the activation energy is constant. From the activation energies at −0.2 V vs SHE, it can be concluded that during HER on VS a first hydrogen atom is adsorbed as a spectator via a Volmer step. Then, the catalytic cycle consists of a Volmer and a Heyrovsky step, with the latter being rate determining. In addition, we investigate for the first time the effect of a conductive support on the HER activity of these sulfur vacancies. Our results show that copper, gold and graphite supports have little effects on the activation energies of all steps. Hence, we conclude that cheap, acid-stable, high-surface area carbon supports are well suited for MoS2-based HER catalysts.

Ligand-Mediated Exfoliation and Antibacterial Activity of 2H Transition-Metal Dichalcogenides.

Transition-metal dichalcogenides (TMDs) exists mainly in two polymorphs, namely, 1T (metallic) and 2H (semiconducting). To tailor the characteristics and practical utility of TMDs for different applications, functionalization is essential. In our earlier studies, we have shown that functionalized 1T and 2H MoS2 exhibit exceptionally high antibacterial activity. The functionalization and related biological applications of other 1T (chemically exfoliated) TMDs were reported, but regarding other 2H TMDs, the functionalization and antibacterial activity are not explored yet. Hence, here we prepared functionalized 2H TMDs such as WS2, WSe2, and MoSe2 other than MoS2 by using a positively charged thiolate surfactant ligand. Further, functionalized 2H TMDs were utilized for antibacterial activity against Gram-positive and Gram-negative bacteria for a comparative antibacterial analysis. Interestingly, we found disparity in activity among the functionalized 2H TMDs, that is, MoS2 shows higher activity than WS2 followed by MoSe2 and WSe2. The intracellular reactive oxygen species measurement was found to be in the order MoS2 > WS2 > MoSe2 > WSe2, which is solely responsible for variation in the activity of functionalized TMDs. These results indicate that the easy functionalization of all types TMDs by using thiol ligand and importance of core material should be considered while designing functionalized material for specific applications.

1T’ RexMo1−xS2–2H MoS2 Lateral Heterojunction for Enhanced Hydrogen Evolution Reaction Performance

AbstractThe imperfect interfaces between 2D transition metal dichalcogenides (TMDs) are suitable for boosting the hydrogen evolution reaction (HER) during water electrolysis. Here, the improved catalytic activity at the spatial heterojunction between 1T’ RexMo1−xS2 and 2H MoS2 is reported. Atomic‐scale electron microscopy confirms that the heterojunction is constructed by an in‐situ two‐step growth process through chemical vapor deposition. Electrochemical microcell measurements demonstrate that the 1T’ RexMo1−xS2–2H MoS2 lateral heterojunction exhibits the best HER catalytic performance among all TMD catalysts with an overpotential of ≈84 mV at 10 mA cm−2 current density and 58 mV dec−1 Tafel slope. Kelvin probe force microscopy shows ≈40 meV as the work function difference between 2H MoS2 and 1T’ RexMo1−xS2, facilitating the electron transfer from 2H MoS2 to 1T’ RexMo1−xS2 at the heterojunction. First‐principles calculations reveal that Mo‐rich heterojunctions with high structural stability are formed, and the HER performance is improved with the combination of increased density of states near the Fermi level and optimal ΔGH* as low as 0.07 eV. Those synergetic effects with many electrons and active sites with optimal ΔGH* improve HER performance at the heterojunction. These results provide new insights into understanding the role of the heterojunction for HER.

Environmental implication of MoS2 nanosheets: Effects on maize plant growth and soil microorganisms

Molybdenum disulfide (MoS2) nanosheets have been used extensively in a variety of fields including medical and industrial. However, little is known about their toxicity effects, especially to edible plants. In this greenhouse study, maize (Zea mays) seedlings were exposed for 4 weeks, through the soil route, to 10 and 100 mg/kg of 2H MoS2 nanosheets. Plant growth, physiological parameters (chlorophyll, antioxidants, and MDA), along with Mo and nutrient element contents were determined in plant tissues. Results showed that at both doses, the nanosheets decreased plant growth. Inductively coupled plasma–mass spectrometry data also showed that both 2H MoS2 concentrations allowed Mo absorption and translocation by maize plants. Additionally, at 100 mg/kg the nanosheets significantly reduced Ca, Mg, Mn, and Zn in leaves, and Na in roots. Gene sequencing data of 16S rRNA showed, that MoS2 nanosheets changed the soil microbial community structure, compared with the untreated control. In addition, nitrogen-fixing microorganisms such as Burkholderiales, Rhizobiales and Xanthobacteraceae were enriched. Overall, the data suggest that, even at low dose (10 mg/kg), the 2H MoS2 nanosheets perturbed both the nutrient uptake by maize plants and the soil microbial communities.

On-Chip Investigation of Electrocatalytic Oxygen Reduction Reaction of 2D Materials.

The on-chip electrocatalytic microdevice (OCEM) is an emerging platform specialized in the electrochemical investigation of single-entity nanomaterials, which is ideal for probing the intrinsic catalytic properties, optimizing performance, and exploring exotic mechanisms. However, the current catalytic applications of OCEMs are almost exclusively in electrocatalytic hydrogen/oxygen evolution reactions with minimized influence from the mass transfer. Here, an OCEM platform specially tailored to investigate the electrocatalytic oxygen reduction reaction (ORR) at a microscopic level by introducing electrolyte convection through a microfluidic flow cell is reported. The setup is established on gold microelectrodes and later successfully applied to investigate how Ar-plasma treatment affects the ORR activities of 2H MoS2 . This study finds that Ar-plasma treatment significantly enhances the ORR performance of MoS2 nanosheets owing to the introduction of surface defects. This study paves the way for highly efficient microscopic investigation of diffusion-controlled electrocatalytic reactions.

Superior Fenton-like and photo-Fenton-like activity of MoS2@TiO2/N-doped carbon nanofibers with phase-regulated and vertically grown MoS2 nanosheets

Molybdenum disulfide (MoS2) nanosheets were recently found to have great potential in heterogeneous Fenton-like reactions, but the synergistic effects of its phase and vertical structure on activating hydrogen peroxide (H2O2) remain ambiguous. Herein, a series of 1 T/2H MoS2@TiO2/NCNFs were constructed by vertically growing trigonal phase (1 T)/hexagonal phase (2H) MoS2 on self-supported titanium dioxide/nitrogen-doped carbon nanofibers (TiO2/NCNFs) for Fenton-like and photo-Fenton-like degradation of tetracycline (TC). It was found that metallic 1 T phase MoS2 favors the dark-Fenton-like reaction, but proper biphase 1 T/2H MoS2 benefit the photo-Fenton-like reaction. This depends on the high electron transport rate of 1 T MoS2 and the photocatalytic effect of 2H MoS2. Significantly, the vertical structure MoS2 nanosheets were much more effective in promoting H2O2 activation than phase regulation. In dark, the reaction rate constant for the optimized vertical 1 T/2H MoS2@TiO2/NCNFs was 0.0246 min−1, which was 16.4 times that for stacked MoS2 (0.0015 min−1). Quenching experiments indicated that •O2–, •OH and h+ were all involved in the photo-Fenton-like reaction, whereas •OH predominated the dark-Fenton-like reaction. The probable TC degradation pathways were investigated and proposed. Besides, the optimized 1 T/2H MoS2@TiO2/NCNFs demonstrated excellent stability, recyclability and adaptability. This work is instructive for designing highly efficient MoS2-based Fenton-like or photo-Fenton-like catalysts.

Metallic-phase of MoS2 as potential electrocatalyst for hydrogen production via water splitting: A brief review

Metallic polymorph of MoS 2 (1T-MoS 2 ) is an emerging and highly promising electrocatalyst owing to its high intrinsic conductivity, large interlayer spacing, hydrophilic surface, high specific surface area, faster in-plane charge transfer, and lower energy barrier for hydrogen adsorption and desorption. This article discusses a brief overview of electrocatalytic property evolutions of metallic 1T-MoS 2 for its application in electrocatalytic hydrogen production via water splitting. A summary is presented on various techniques that have been reported to date for developing the 1T-MoS 2 phase and their efficacy towards electrocatalytic hydrogen generation. This review also explains the thermodynamic parameter dependence of electrocatalytic enhancements of metallic MoS 2 with state-of-the-art theoretical reasoning and experimental details. The Gibbs free energy of adsorption/desorption of H 2 in 1T-MoS 2 is lower, and therefore outperforms electrocatalytic hydrogen production with respect to 2H–MoS 2 . The various engineering strategies, applied on the material, open avenues for systems devoted to water splitting. • Metallic polymorph (1T-MoS 2 ) of 2D-MoS 2 is an emerging and promising electrocatalyst for Hydrogen Evolution Reaction (HER). • 1T-MoS 2 exhibits lower Gibbs free energy of H 2 adsorption/desorption, thereby outperforms 2H–MoS 2 as electrocatalyst. • Various strategies are discussed for effective phase transition of 2D-MoS 2 from semiconducting (2H) to metallic (1T) MoS 2 . • Bandgap engineering, exposing active sites, and Fermi level alignment have shown extraordinary results for enhancing HER.

Enhanced photoresponse of InxMo1-xS2 (X = 0.05 and 0.1) nanosheets for PEC type photodetector

Transition metal chalcogenides (TMDCs) have great potential in the field of solid state photodetectors and photoelectrochemical (PEC) type photodetector owing to high carrier mobility and suitable energy band gap. Two dimensional MoS2, most intensively investigated member of TMDCs, has shown excellent photoresponsivity in the visible range owing to excitonic transition and suitable electronic structure. Herein, we demonstrate the PEC photodetector based on InxMo1-xS2 nanosheets. High yield liquid phase exfoliation techniques have been employed for the synthesis of InxMo1-xS2 nanosheets. InxMo1-xS2 nanosheets have hexagonal lattice structure with highly crystalline behavior and X-ray diffraction confirms the doping of indium in 2H–MoS2. PEC type detectors show 582 μA/W and 107 μA/W photoresponsivity for In0.05Mo0.95S2 and In0.1Mo0.9S2 nanosheets by optimized concentration of indium. Present investigation advocates the significant development in the field of opto-electronics and photoelectrochemical cells for generation clean energy.

Piezo-photocatalysis over phase-engineered MoSe2 modified Bi2WO6 hierarchical microspheres: Utilizing piezoelectric effect to enhance photocatalytic performance

Photocatalysis technology is regarded as a promising way to ease the energy crisis and develop the sustainability of human society. However, the photocatalytic performance still suffers from critical charge recombination due to insufficient driving force. Herein, piezocatalysis and photocatalysis are judiciously combined to enable efficient piezo-photocatalytic activity, by synthesizing novel 1T/2H MoSe2/Bi2WO6 (1T/2H MS/BWO) and 2H MoSe2/Bi2WO6 (2H MS/BWO) hierarchical microspheres. The optimal 1T/2H MS/BWO piezo-photocatalyst exhibits excellent degradation activity of diclofenac (DCF) under the combined action of sunlight and ultrasound, achieving degradation efficiency of 99.9% in 60 min, which is significantly promoted than that of 2H MS/BWO and pure BWO. Piezoresponse force microscopy and ferroelectric analyzer results demonstrate that the 1T/2H MS/BWO composite generates a strong polarization electric field, which could act as powerful driving force to accelerate carriers separation and thus improve the piezo-photocatalytic activity. Moreover, several characterizations of 1T/2H MoSe2 and 2H MoSe2 reveal that the 1T/2H MoSe2 displayed larger surface area, better light absorption, more active sites and more favorable band position than 2H MoSe2. Finally, mechanism studies including degradation pathways and possible intermediates during DCF degradation were investigated by density functional theory (DFT) calculations and liquid chromatography-mass spectrometry (LC-MS).

Rational design of selenium inserted 1T/2H mixed-phase molybdenum disulfide for energy storage and pollutant degradation applications

MoS2 based materials are recognized as the promising candidate for multifunctional applications due to its unique physicochemical properties. But presence of lower number of active sites, poor electrical conductivity, and less stability of 2H and 1T MoS2 inherits its practical applications. Herein, we synthesized the Se inserted mixed-phase 2H/1T MoS2 nanosheets with abundant defects sites to achieve improved overall electrochemical activity. Moreover, the chalcogen insertion induces the recombination of photogenerated excitons and enhances the life of carriers. The bifunctional energy storage and photocatalytic pollutant degradation studies of the prepare materials are carried out. Fabricated symmetric solid-state supercapacitor showed an exceptional capacitance of 178 mF cm−2 with an excellent energy density of 8 μWh cm−2 and power density of 137 mW cm−2, with remarkable capacitance retention of 86.34% after successive 8000 charge–discharge cycles. The photocatalytic dye degradation experiments demonstrate that the prepared Se incorporated 1T/2H MoS2 is a promising candidate for dye degradation applications. Further, the DFT studies confirmed that the Se inserted MoS2 is a promising electrode material for supercapacitor applications with higher CQ due to a larger density of states near Fermi level as compared to pristine MoS2.