Search results for "molybdenum disulfide"

Fast Polymeric Functionalization Approach for the Covalent Coating of MoS2 Layers

2021

We present the covalent coating of chemically exfoliated molybdenum disulfide (MoS2) based on the polymerization of functional acryl molecules. The method relies on the efficient diazonium anchoring reaction to provoke the in situ radical polymerization and covalent adhesion of functional coatings. In particular, we successfully implement hydrophobicity on the exfoliated MoS2 in a direct, fast, and quantitative synthetic approach. The covalent functionalization is proved by multiple techniques including X-ray photoelectron spectroscopy and TGA-MS. This approach represents a simple and general protocol to reach dense and homogeneous functional coatings on 2D materials.

Substrate impact on the thickness dependence of vibrational and optical properties of large area $MoS_2$ produced by gold-assisted exfoliation

2021

The gold-assisted exfoliation is a very effective method to produce large-area ($cm^2$-scale) membranes of molybdenum disulfide ($MoS_2$) for electronics. However, the strong $MoS_2/Au$ interaction, beneficial for the exfoliation process, has a strong impact on the vibrational and light emission properties of $MoS_2$. Here, we report an atomic force microscopy (AFM), micro-Raman ($\mu-R$) and micro-Photoluminescence ($\mu-PL$) investigation of $MoS_2$ with variable thickness exfoliated on Au and subsequently transferred on an $Al_2O_3/Si$ substrate. The $E_{2g}$ - $A_{1g}$ vibrational modes separation $\Delta\mu$ (typically used to estimate $MoS_2$ thickness) exhibits an anomalous large val…

Deterministic Modification of CVD Grown Monolayer MoS2 with Optical Pulses

2021

| openaire: EC/H2020/820423/EU//S2QUIP | openaire: EC/H2020/834742/EU//ATOP Transition metal dichalcogenide monolayers have demonstrated a number of exquisite optical and electrical properties. Here, the authors report the optical modification of topographical and optical properties of monolayer MoS2 with femtosecond pulses under an inert atmosphere. A formation of three-dimensional structures on monolayer MoS2 with tunable height up to ≈20 nm is demonstrated. In contrast to unmodified monolayer MoS2, these optically modified structures show significantly different optical properties, such as lower photoluminescence intensity and longer fluorescence lifetime. The results suggest a novel way…

Overcoming the Insolubility of Molybdenum Disulfide Nanoparticles through a High Degree of Sidewall Functionalization Using Polymeric Chelating Ligan…

2006

Ambipolar MoS2 Transistors by Nanoscale Tailoring of Schottky Barrier Using Oxygen Plasma Functionalization

2017

One of the main challenges to exploit molybdenum disulfide (MoS2) potentialities for the next-generation complementary metal oxide semiconductor (CMOS) technology is the realization of p-type or ambipolar field-effect transistors (FETs). Hole transport in MoS2 FETs is typically hampered by the high Schottky barrier height (SBH) for holes at source/drain contacts, due to the Fermi level pinning close to the conduction band. In this work, we show that the SBH of multilayer MoS2 surface can be tailored at nanoscale using soft O-2 plasma treatments. The morphological, chemical, and electrical modifications of MoS2 surface under different plasma conditions were investigated by several microscopi…

Optical Modification of Monolayer MoS 2 : Deterministic Modification of CVD Grown Monolayer MoS 2 with Optical Pulses (Adv. Mater. Interfaces 10/2021)

2021

Smart molecular/MoS2 Heterostructures Featuring Light and Thermally-Induced Strain Driven by Spin Switching

2020

In this work we exploit the ability of spin-crossover molecules to switch between two spin states, upon the application of external stimuli, to prepare smart molecular/2D heterostructures. Through the chemical design of the hybrid interface, that involves a covalent grafting between the two components, we obtain a hybrid heterostructure formed by spin-crossover nanoparticles anchored on chemically functionalized monolayers of semiconducting MoS2. In the resulting hybrid, the strain generated by the molecular system over the MoS2 layer, as a consequence of a thermal or light-induced spin switching, results in a dramatic and reversible change of its electrical and optical properties. This nov…