It is generally accepted that liquid-phase exfoliation (LPE) enables large-scale production of few-layer MoS flakes. In our work, we studied in detail few-layer MoS oxidation in the course of standard LPE in a water/ethanol solution. We demonstrate that an increase of the initial MoS concentration above a certain threshold triggers a pronounced oxidation and the exfoliation process starts to produce MoO nanoparticles. A subsequent decrease of the water pH along with an increased content of SO suggests an oxidation scenario of few-layer MoS oxidation towards MoO nanoparticles. Moreover, the lowered pH leads to agglomeration and sedimentation of the few-layer MoS flakes, which significantly lowers their production yield. We employed a large number of physico-chemical techniques to study the MoS-to-MoO transformation and found a threshold value of 10 mg ml of the initial MoS concentration to trigger this transformation.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/c9cp01951k | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Attoampere Level Leakage Current in Chemical Vapor Deposition-Grown Monolayer MoS Dynamic Random-Access Memory in Trap-Assisted Tunneling Limit.
ACS Nano
January 2025
BK21 Graduate Program in Intelligent Semiconductor Technology, Seoul 03722, Republic of Korea.
MoS, one of the most researched two-dimensional semiconductor materials, has great potential as the channel material in dynamic random-access memory (DRAM) due to the low leakage current inherited from the atomically thin thickness, high band gap, and heavy effective mass. In this work, we fabricate one-transistor-one-capacitor (1T1C) DRAM using chemical vapor deposition (CVD)-grown monolayer (ML) MoS in large area and confirm the ultralow leakage current of approximately 10 A/μm, significantly lower than the previous report (10 A/μm) in two-transistor-zero-capacitor (2T0C) DRAM based on a few-layer MoS flake. Through rigorous analysis of leakage current considering thermionic emission, tunneling at the source/drain, Shockley-Read-Hall recombination, and trap-assisted tunneling (TAT) current, the TAT current is identified as the primary source of leakage current.
View Article and Find Full Text PDFStacking Engineering toward Giant Second Harmonic Generation in Twisted Graphene Superstructures.
J Am Chem Soc
January 2025
Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
The nonlinear optical response in graphene is finding increasing applications in nanophotonic devices. The activation and enhancement of second harmonic generation (SHG) in graphene, which is generally forbidden in monolayer and AB-stacked bilayer graphene due to their centrosymmetry, is of urgent need for nanophotonic applications. Here, we present a comprehensive study of SHG performance of twisted multilayer graphene structures based on stacking engineering.
View Article and Find Full Text PDFCompetition between Bipolar Conduction Modes in Extrinsically -Doped MoS: Interaction with Gate Dielectric Matters.
ACS Nano
December 2024
Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.
With reduced dimensionality and a high surface area-to-volume ratio, two-dimensional (2D) semiconductors exhibit intriguing electronic properties that are exceptionally sensitive to surrounding environments, including directly interfacing gate dielectrics. These influences are tightly correlated to their inherent behavior, making it critical to examine when extrinsic charge carriers are intentionally introduced to the channel for complementary functionality. This study explores the physical origin of the competitive transition between intrinsic and extrinsic charge carrier conduction in extrinsically -doped MoS, highlighting the central role of interactions of the channel with amorphous gate dielectrics.
View Article and Find Full Text PDFDual-Gate Modulation in a Quantum Dots/MoS Thin-Film Transistor Gas Sensor.
ACS Sens
December 2024
School of Integrated Circuits, Wuhan National Laboratory for Optoelectronics, Optics Valley Laboratory, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
Mastering the surface chemistry of quantum dots (QDs) has enabled a remarkable gas-sensing response as well as impressive air stability. To overcome the intrinsic receptor-transducer mismatch of QDs, PbS QDs used as sensitive NO receptors are spin-coated on top of a few-layer MoS and incorporated into a thin-film transistor (TFT) gas sensor. This architecture enables the separation of the electron transduction function from the chemical reception function.
View Article and Find Full Text PDFA Reconfigurable Polarimetric Photodetector Based on the MoS/PdSe Heterostructure with a Charge-Trap Gate Stack.
Nanomaterials (Basel)
December 2024
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Besides the intensity and wavelength, the ability to analyze the optical polarization of detected light can provide a new degree of freedom for numerous applications, such as object recognition, biomedical applications, environmental monitoring, and remote sensing imaging. However, conventional filter-integrated polarimetric sensing systems require complex optical components and a complicated fabrication process, severely limiting their on-chip miniaturization and functionalities. Herein, the reconfigurable polarimetric photodetection with photovoltaic mode is developed based on a few-layer MoS/PdSe heterostructure channel and a charge-trap structure composed of AlO/HfO/AlO (AHA)-stacked dielectrics.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!