Monolayer material’s electronic properties can be controlled by constructing heterostructures, such as transition metal dichalcogenides (TMDCs) heterostructures. Among them, heterostructures with a ...new direct Z-scheme electronic band structure are promising solar-driven water splitting photocatalysts. In this work, the first principle calculation based on Density functional theory (DFT) was used to study the structure, electrical properties and optical properties of MoSSe/MoSTe heterostructures. By vertically stacking MoSSe and MoSTe monolayers and via lattice relaxation, 12 different MoSTe/MoSSe heterostructure models have been constructed. Model 1 (TeMoS/SeMoS) and model 2 (SMoTe/SMoSe) are novel direct Z-scheme heterostructure and traditional type II band configurations, respectively. Compared to type II heterostructures, direct Z-scheme arrangement can achieve more efficient spatial separation of photogenerated carriers, increase the lifetime of minority carriers while retaining the redox ability of internal carriers. And compared to monolayer materials, MoSTe/MoSSe heterostructures exhibit stronger and broader optical absorption. Additionally, the conduction band edge potential of MoSTe in the heterostructure is negative to the H+/H2O electrode potential, and the valence band edge potential of MoSSe is positive to the O2/H2O electrode potential. It can be inferred that MoSTe/MoSSe heterostructure has strong reduction and oxidation capabilities, and can achieve total water-splitting reaction. Further Gibbs free energy calculation found that the MoSSe/MoSTe heterostructure can spontaneously conduct thermodynamic water splitting under the light in both acidic and neutral environments, and the theoretical hydrogen production efficiency is 16.7 %.
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•Bilayer MoSTe does not have enhanced optical absorption than single-layer MoSTe.•Single-layer MoSTe has no solar water splitting ability for lack of suitable band edges.•Bilayer MoSTe has favorable ...band edges for solar water splitting.
Single-layer and bilayer Janus transition metal dichalcogenides (TMDCs) attain great attention for possible application in solar water splitting. The crucial issues for solar water splitting are the band edge positions and optical absorption of photocatalysts. However, for this large group of Janus TMDCs materials, their optical absorption correction by the effective unit cell volume and the charge distribution of band edges, were not investigated in most previous works. To clarify these issues, we herein studied the electronic and optical properties of typical single-layer and bilayer MoSTe using first-principles calculations. Remarkably, when corrected by the effective unit cell volume, the optical absorption of bilayer MoSTe is not enhanced when compared to that of single-layer MoSTe. On the other hand, single-layer MoSTe possesses no solar water-splitting ability for lack of suitable band edges, when the charge distribution of band edges is considered. Furthermore, favorable band edges for water splitting were achieved in bilayer MoSTe. In brief, this work emphasized the optical absorption correction by the effective unit cell volume and the charge distribution of band edges when searching for 2D photocatalysts stacking by Janus monolayers.
Using first-principle calculations, we investigate the impact of strain on the electronic structures and effective masses of Janus WSTe and MoSTe monolayers. The calculations were performed using the ...QUANTUM-ESPRESSO package, employing the PBE and HSE06 functionals. Our results demonstrate that strain fundamentally changes the electronic structures of the Janus WSTe and MoSTe monolayers. We observe that deformation causes a shift in the maxima and minima of the valence and conduction bands, respectively. We find that the effective electrons and hole masses of MoSTe and WSTe can be changed by deformation. In addition, the strain’s effect on carrier mobility is also investigated in this work via the deformation potential theory.
This paper deals with a new method for determining the shading of surfaces by means of terrestrial laser scanner measurements and two specially designed computer programs, which, for any selected ...observation point, can determine the contour of the terrain, the position of the sun, and insolation over time. The method was applied to the Moste dam, where, after scanning of the area of the dam, the contours of the terrain were determined from ten observation points located along the axis of the dam's downstream surface, for azimuths of 80° to 280° at a selected horizontal angle and step of 5°. In order to exclude stray points, quantiles of 0.998 and 0.997 were selected. The results of calculations made using the two applied variants were very similar, thus indicating a minuscule number of stray points. Very reliable results were already obtained when using the quantile of 0.998. The results of the measurements and the calculations of shading at the Moste mobile automatic weather station, over a period of seven consecutive clear days in early August 2013, showed very good agreement, confirming that the described method for determining of shading is highly reliable.
Provider: - Institution: - Data provided by Europeana Collections- Inženir Vidmar (na sliki stoji) in tehnik Špiler pri montaži projektorja v novem kinu Triglav. Po Vidmarjevi originalni konstrukciji ...so v tovarni za elektrotehniko in fino mehaniko Iskra v Kranju serijsko izdelovali projektorje in ojačevalce. - All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: - Institution: - Data provided by Europeana Collections- Pogled na poslovno stavbo BTC- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 ...1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: - Institution: - Data provided by Europeana Collections- Moste pri Žirovnici – most čez potok Završnico. Razglednica je bila odposlana 7. junija 1928.- All metadata published by Europeana ...are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: - Institution: - Data provided by Europeana Collections- Růžena Celerová, Marie (Mája) Kohoutová- All metadata published by Europeana are available free of restriction under the Creative ...Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: - Institution: - Data provided by Europeana Collections- Obvestilo o investitorju in izvajalcih del na trasi PST od severne obvoznice do tirnih naprav v Mostah. - All metadata published by ...Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
•Simple reaction process employed to synthesis the MoS2@Mo2C and MoS2@W2C hybrid.•Hydrogen evolution explored the low overpotential and Tafel slope in base and acid.•High specific capacitance of 1040 ...Fg−1 @ 0.5 A.g−1 with better rate capability.•Symmetric capacitor exposed 349 F.g−1 at 0.5 A.g−1 with 97 Wh.kg−1 at 0.5 kW.kg−1.•First principle DFT calculation derived the superior catalytic behavior in MoS2@Mo2C.
Engineering the active sites is a promising approach to boost electrode enactment for various electrochemical applications. Herein, highly conductive Mo2C and W2C were interfaced with the layered MoS2 as the efficient material for symmetric supercapacitors and water splitting. For the first time, systematically fabricated MoS2@Mo2C and MoS2@W2C hybrid supercapacitor electrodes explored the excellent specific capacitance of 1040 and 681 F.g−1 at 0.5 A.g−1 current density, respectively, and robust long-term cycling in the half-cell measurements. Moreover, the customized symmetric supercapacitors using MoS2@Mo2C electrode showed a 349 F.g−1 capacitance at 0.5 A.g−1 current density with a maximum energy density of 48 Wh.kg−1 at 0.25 kW.kg−1 power density. MoS2@Mo2C hybrid hydrogen evolution catalysts produced the low overpotentials and small Tafel slopes in the acidic and alkaline media which ascertained their plentiful edges and high conductance. Density functional theory calculations disclosed that incorporation of X2C (X = Mo or W) with the layered MoS2 can be improved to acquire more ideal energy for adsorption of hydrogen at the catalyst surface. The proposed strategy of metal carbides blended layered metal chalcogenides proved their expertise by hypothetical and experimental results, could be created the new platform to extend their uses for various future energy applications.
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