Atomically thin MoS2: a new direct-gap semiconductor
TLDR
The electronic properties of ultrathin crystals of molybdenum disulfide consisting of N=1,2,…,6 S-Mo-S monolayers have been investigated by optical spectroscopy and the effect of quantum confinement on the material's electronic structure is traced.Abstract:
The electronic properties of ultrathin crystals of molybdenum disulfide consisting of N=1,2,…,6 S-Mo-S monolayers have been investigated by optical spectroscopy Through characterization by absorption, photoluminescence, and photoconductivity spectroscopy, we trace the effect of quantum confinement on the material's electronic structure With decreasing thickness, the indirect band gap, which lies below the direct gap in the bulk material, shifts upwards in energy by more than 06 eV This leads to a crossover to a direct-gap material in the limit of the single monolayer Unlike the bulk material, the MoS₂ monolayer emits light strongly The freestanding monolayer exhibits an increase in luminescence quantum efficiency by more than a factor of 10⁴ compared with the bulk materialread more
Citations
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Plasma-engineered MoS2 thin-film as an efficient electrocatalyst for hydrogen evolution reaction
TL;DR: It is shown that the Ar or O2 plasma can be used to generate a large number of physical and chemical defects in 2D crystals to modify the electronic properties and increase the number of active sites in MoS2.
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Novel effects of strains in graphene and other two dimensional materials
B. Amorim,B. Amorim,Alberto Cortijo,F. de Juan,F. de Juan,Adolfo G. Grushin,Francisco Guinea,Francisco Guinea,Francisco Guinea,A. Gutierrez-Rubio,Hector Ochoa,Hector Ochoa,Vincenzo Parente,Vincenzo Parente,Rafael Roldán,Pablo San-Jose,Jürgen Schiefele,Mauricio Sturla,María A. H. Vozmediano +18 more
TL;DR: In this paper, the role of strains in the structural and electronic properties of graphene and other two-dimensional compounds is discussed. But the role is not restricted to graphene, and they are being intensively studied in other two dimensional materials, such as the metallic dichalcogenides.
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Splitting between bright and dark excitons in transition metal dichalcogenide monolayers
TL;DR: In this paper, the Bethe-Salpeter equation was solved with $G\phantom{\rule{0}{0ex}}W$ wave functions in order to determine the sign and amplitude of the splitting between bright and dark exciton states in the entire Mo{X}_{2}$ and W${X}$ monolayer family.
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One-Step Synthesis of Water-Soluble MoS2 Quantum Dots via a Hydrothermal Method as a Fluorescent Probe for Hyaluronidase Detection
TL;DR: A novel fluorescence sensor for Hyaluronidase (HAase), an endoglucosidase, can cleave HA into proangiogenic fragments and lead to the aggregation of gold nanoparticles and the electron transfer is blocked and fluorescence is recovered.
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Recent Advances in Synthesis and Biomedical Applications of Two-Dimensional Transition Metal Dichalcogenide Nanosheets.
TL;DR: A comprehensive overview of different synthetic methods of ultrathin 2D TMDC NSs and their state-of-the-art biomedical applications, especially those that have appeared in the past few years, is presented.
References
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Journal ArticleDOI
Measurement of the Elastic Properties and Intrinsic Strength of Monolayer Graphene
TL;DR: Graphene is established as the strongest material ever measured, and atomically perfect nanoscale materials can be mechanically tested to deformations well beyond the linear regime.
Journal ArticleDOI
Two-dimensional atomic crystals
Kostya S. Novoselov,Da Jiang,Fred Schedin,Timothy J. Booth,V. V. Khotkevich,Sergey V. Morozov,Andre K. Geim +6 more
TL;DR: By using micromechanical cleavage, a variety of 2D crystals including single layers of boron nitride, graphite, several dichalcogenides, and complex oxides are prepared and studied.
Journal ArticleDOI
Emerging Photoluminescence in Monolayer MoS2
Andrea Splendiani,Liang Sun,Yuanbo Zhang,Tianshu Li,Jonghwan Kim,Chi-Yung Chim,Giulia Galli,Feng Wang,Feng Wang +8 more
TL;DR: This observation shows that quantum confinement in layered d-electron materials like MoS(2), a prototypical metal dichalcogenide, provides new opportunities for engineering the electronic structure of matter at the nanoscale.
Journal ArticleDOI
Anomalous lattice vibrations of single- and few-layer MoS2.
TL;DR: This work exemplifies the evolution of structural parameters in layered materials in changing from the three-dimensional to the two-dimensional regime by characterized by Raman spectroscopy.
Journal ArticleDOI
The transition metal dichalcogenides discussion and interpretation of the observed optical, electrical and structural properties
J.A. Wilson,A.D. Yoffe +1 more
TL;DR: The transition metal dichalcogenides are about 60 in number as discussed by the authors, and two-thirds of these assume layer structures and can be cleaved down to less than 1000 A and are then transparent in the region of direct band-to-band transitions.