Transition Metal Dichalcogenides: Synthesis and Application

Dear Colleagues,

Single layered (2D) transition metal dichalcogenides (TMDCs), like MoS2, MoSe2, WS2, and WSe2, are a prominent example of new materials with unique optical and electronic properties. Such materials behave as 2D semiconductors with bandgaps lying in the visible and IR ranges. In the monolayer limit, TMDCs are of particular interest, as their bandgaps become direct, which enables an enhanced strong light–matter interaction. As a result, the resonant excitonic absorption of a single TMD monolayer can be as large as 5%–20%. Strong excitonic resonances govern the optical properties of 2D TMDCs because of their reduced dielectric screening and strong Coulomb interactions between the charged particles (electrons and holes). As a result, such excitons have large binding energies of 0.2–0.8 eV. Moreover, charged excitons (trions) and excitonic molecules have also been demonstrated at low temperatures.

Because of the monolayer nature of 2D-TMDCs, their high oscillator strength, high charge mobility, and the potential for tuning, these materials have become a unique class of 2D materials for optoelectronic applications. Today, they are used for photodetection and light harvesting, phototransistors, and light-emitting diodes. The emission quantum yield of these materials depends on many factors, including fabrication techniques (mechanical exfoliation or chemical vapor deposition), type of substrate, defects, and so on. Typically, as-prepared 2D-TMDCs have a relatively low quantum yield of ~0.1%–10%. It has been shown that such low values of the quantum yield can be significantly improved by coupling to specifically tailored resonant optical nanocavities and metasurfaces. All of this makes 2D-TMDCs up-and-coming candidates for modern optoelectronics and photonics applications.

The Special Issue of the journal of Applied Sciences, “Transition Metal Dichalcogenides: Synthesis and Application”, aims to cover the recent research progress in the areas of 2D TMDC materials fabrication, and advanced optoelectronics and photonics applications.

Prof. Dr. Alex Krasnok
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Applied Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• 2D transition metal dichalcogenides
• Excitonic resonances
• Strong light–matter interaction
• Emission quantum yield
• Strong coupling
• Purcell effect
• Nanoantennas
• Metasurfaces
• Photonics
• Optoelectronics