Roll‐to‐Roll Production of Layer‐Controlled Molybdenum Disulfide: A Platform for 2D Semiconductor‐Based Industrial Applications

Abstract

A facile methodology for the large-scale production of layer-controlled MoS layers on an inexpensive substrate involving a simple coating of single source precursor with subsequent roll-to-roll-based thermal decomposition is developed. The resulting 50 cm long MoS layers synthesized on Ni foils possess excellent long-range uniformity and optimum stoichiometry. Moreover, this methodology is promising because it enables simple control of the number of MoS layers by simply adjusting the concentration of (NH ) MoS . Additionally, the capability of the MoS for practical applications in electronic/optoelectronic devices and catalysts for hydrogen evolution reaction is verified. The MoS -based field effect transistors exhibit unipolar n-channel transistor behavior with electron mobility of 0.6 cm V s and an on-off ratio of ≈10³. The MoS -based visible-light photodetectors are fabricated in order to evaluate their photoelectrical properties, obtaining an 100% yield for active devices with significant photocurrents and extracted photoresponsivity of ≈22 mA W . Moreover, the MoS layers on Ni foils exhibit applicable catalytic activity with observed overpotential of ≈165 mV and a Tafel slope of 133 mV dec . Based on these results, it is envisaged that the cost-effective methodology will trigger actual industrial applications, as well as novel research related to 2D semiconductor-based multifaceted applications.

Solution-Based Synthesis of Few-Layer WS2 Large Area Continuous Films for Electronic Applications

“…The device field effect characteristics are dictated by the nanocrystalline nature of the film as well as ambient adsorbates. However, as it has been shown with MoS 2 films that are grown in similar ways, we expect a dramatic improvement when the device is optimized and operated in a top-gate configuration with a high-k dielectric such as HfO 2 13 or ionic liquid gate 14,18 .…”

“…Solution-based synthesis is compatible with existing nanofabrication processes, is scalable at low cost and has already been shown to produce high quality MoS 2 films using a single source precursor such as ammonium tetrathiomolybdate (NH 4 ) 2 MoS 4 through thermal decomposition for electronic devices applications 10 . Therefore, several groups have developed approaches for large area solution-based MoS 2 synthesis via two-step thermolysis of (NH 4 ) 2 MoS 4 films coated in different ways such as dip, roll to roll and spin coating [11][12][13][14][15][16][17][18] . Spin coating of (NH 4 ) 2 MoS 4 solution in particular is highly preferable among other coating techniques due to its integration with current semiconductor technology and its ability to control the initial precursor film thickness through spinning speed as well as precursor solution concentration 13,17 .…”

Multiscale computational understanding and growth of 2D materials: a review

“…Two main approaches have been employed for the synthesis of 2D materials, i.e., (i) top-down approaches such as mechanical 2 and liquid-phase exfoliation that allows scalability 3 , and (ii) bottom-up approaches such as chemical vapor deposition (CVD) and atomic layer deposition techniques 4 . The former approaches are suitable for mass production of 2D materials but with typically lower quality, whereas the latter approaches can produce high-quality 2D materials but in small amounts.…”

Precious‐Metal‐Free Electrocatalysts for Activation of Hydrogen Evolution with Nonmetallic Electron Donor: Chemical Composition Controllable Phosphorous Doped Vanadium Carbide MXene

“…Thus, replacing expensive and rare catalysts with earth‐abundant materials still attracts many scientists hoping to make hydrogen production be economically competitive . Over past few years, many possible alternatives such as 2D materials (heteroatom‐doped graphene and MoS 2 ) and transition metal nonoxides (sulfides, carbides, nitrides, and phosphides) have been synthesized to replace the Pt‐based electrocatalysts, because of their d‐band states similar to Pt . However, except for a few cases, the true electrocatalytic performance of these alternatives is still far from what is needed for industrial applications.…”