A5008302202- 2D Materials and Applications
- MXene and MAX Phase Materials
- Graphene research and applications
- Metamaterials and Metasurfaces Applications
- Perovskite Materials and Applications
- Terahertz technology and applications
- Plasmonic and Surface Plasmon Research
- Gyrotron and Vacuum Electronics Research
- Photonic Crystals and Applications
- Advanced Antenna and Metasurface Technologies
- Advanced Sensor and Energy Harvesting Materials
- Chalcogenide Semiconductor Thin Films
- Photonic and Optical Devices
- Gas Sensing Nanomaterials and Sensors
- Molecular Junctions and Nanostructures
- Conducting polymers and applications
- Laser-Matter Interactions and Applications
- Advanced Fiber Laser Technologies
- Analytical Chemistry and Sensors
- Advanced biosensing and bioanalysis techniques
- Quantum Dots Synthesis And Properties
- Superconducting and THz Device Technology
- Antenna Design and Analysis
- Advanced Memory and Neural Computing
- Pulsed Power Technology Applications
Chang'an University
2025
Ministry of Water Resources of the People's Republic of China
2025
Suzhou Institute of Nano-tech and Nano-bionics
2020-2024
Chinese Academy of Sciences
2020-2024
University of Science and Technology of China
2024
Tsinghua–Berkeley Shenzhen Institute
2019-2022
Tsinghua University
2019-2022
Tianjin University
2018-2022
Collaborative Innovation Center of Chemical Science and Engineering Tianjin
2018-2022
Nanjing University of Posts and Telecommunications
2021
Abstract Few‐layered films of WS 2 , synthesized by chemical vapor deposition on quartz, are successfully used as light sensors. The film samples structurally characterized Raman spectroscopy, atomic force microscopy, scanning electron and high‐resolution transmission microscopy. produced consist few layered sheets possessing up to 10 layers. UV–visible absorbance spectra reveals absorption peaks at energies 1.95 2.33 eV, consistent with the A B excitons characteristic . Current–voltage ( I...
The isolation of few-layered transition metal dichalcogenides has mainly been performed by mechanical and chemical exfoliation with very low yields. In this account, a controlled thermal reduction-sulfurization method is used to synthesize large-area (~1 cm(2)) WS2 sheets thicknesses ranging from monolayers few layers. During synthesis, WOx thin films are first deposited on Si/SiO2 substrates, which then sulfurized (under vacuum) at high temperatures (750-950 °C). An efficient route transfer...
It is a challenge to fabricate graphene bulk materials with properties arising from the nature of individual sheets, and which assemble into monolithic three-dimensional structures. Here we report scalable self-assembly randomly oriented sheets additive-free, essentially homogenous sponge that provide combination both cork-like rubber-like properties. These sponges, densities similar air, display Poisson's ratios in all directions are near-zero largely strain-independent during reversible...
Although the main Raman features of semiconducting transition metal dichalcogenides are well known for monolayer and bulk, there important differences exhibited by few layered systems which have not been fully addressed. WSe2 samples were synthesized ab-initio calculations carried out. We calculated phonon dispersions Raman-active modes in systems: WSe2, MoSe2, WS2 MoS2 ranging from monolayers to five-layers bulk. First, we confirmed that as number layers increase, E′, E″ E2g shift lower...
Substitutional doping of transition metal dichalcogenides (TMDs) may provide routes to achieving tunable p-n junctions, bandgaps, chemical sensitivity, and magnetism in these materials. In this study, we demonstrate situ monolayer molybdenum disulfide (MoS2) with manganese (Mn) via vapor phase deposition techniques. Successful incorporation Mn MoS2 leads modifications the band structure as evidenced by photoluminescence X-ray photoelectron spectroscopy, but is heavily dependent on choice...
Here we report the properties of field-effect transistors based on few layers chemical vapor transport grown alpha- MoTe_2 crystals mechanically exfoliated onto SiO_2. We performed and Hall mobility measurements, as well Raman scattering transmission electron microscopy. In contrast to both MoS_2 MoSe_2, our (FETs) are observed be hole-doped, displaying on/off ratios surpassing 106 typical sub-threshold swings ~ 140 mV per decade. Both mobilities indicate maximum values approaching or 10...
Defects play a significant role in tailoring the optical properties of two-dimensional materials. Optical signatures defect-bound excitons are important tools to probe defective regions and thus interrogate quality as-grown semiconducting monolayer We have performed systematic study using photoluminescence (PL) spectroscopy combined with atomically resolved scanning electron microscopy first-principles calculations. Spatially PL at low temperatures revealed bound that were present only on...
Resonant Raman spectroscopy (RRS) is a very useful tool to study physical properties of materials since it provides information about excitons and their coupling with phonons. We present in this work RRS samples WSe2 one, two, three layers (1L, 2L, 3L), as well bulk 2H-WSe2, using up 20 different laser lines covering the visible range. The first- second-order features exhibit resonant behavior, agreement double (and triple) resonance mechanism(s). From energy dependence intensities (Raman...
Above-light-line surface plasmon polaritons can arise at the interface between a metal and epsilon-near-zero metamaterial. This unique feature induces unusual fast-wave non-radiative modes in material/metal bilayer. Excitation of this peculiar mode leads to wide-angle perfect absorption low-loss ultrathin metamaterials. The ratio wavelength thickness metamaterial be as high 10^4; electromagnetic energy confined layer thin {\lambda}/10000. Unlike conventional leaky modes, these have...
Significance The gas-sensing performance of graphene could be remarkably enhanced by incorporating dopants into its lattice based on theoretical calculations. However, to date, experimental progress boron-doped (BG) is still very scarce. Here, we achieved the controlled growth large-area, high-crystallinity BG sheets and shed light their electronic features associated with boron at atomic scale. As a proof-of-concept, it demonstrated that doping in lead much sensitivity when detecting toxic...
N-doped graphene can be used as a substrate for different molecules to effectively enhance their Raman scattering signal.
Abstract Epidermal electronics have been developed with gas/sweat permeability for long‐term wearable electrophysiological monitoring. However, the state‐of‐the‐art breathable epidermal ignore sweat accumulation and immersion at skin/device interface, resulting in serious degradation of interfacial conformality adhesion, leading to signal artifacts unstable inaccurate biopotential measurements. Here, authors present an all‐nanofiber‐based Janus electrode endowed directional transport...
Hydrogels offer tissue-like softness, stretchability, fracture toughness, ionic conductivity, and compatibility with biological tissues, which make them promising candidates for fabricating flexible bioelectronics. A soft hydrogel film offers an ideal interface to directly bridge thin-film electronics the tissues. However, it remains difficult fabricate a ultrathin configuration excellent mechanical strength. Here we report tissue-inspired ultrasoft microfiber composite (< 5 μm) film, is...
We show explicitly that the well-known Gouy phase shift of any focused beam originates from transverse spatial confinement, which, through uncertainty principle, introduces a spread in momenta and hence expectation value axial propagation constant. A general expression is given for terms values squares momenta. Our result also explains front Kirchhoff diffraction integral.
Resonant Raman spectroscopy is a powerful tool for providing information about excitons and exciton–phonon coupling in two-dimensional materials. We present here resonant experiments of single-layered WS2 WSe2 using more than 25 laser lines. The excitation profiles both materials show unexpected differences. All features monolayers are enhanced by the first-optical excitations (with an asymmetric response spin–orbit related XA XB excitons), whereas bands not at XA/B energies. Such intriguing...
Chemical vapor deposition (CVD) is a scalable method able to synthesize MoS2 and WS2 monolayers. In this work, we reduced the synthesis temperature by 200 °C only introducing tellurium (Te) into CVD process. The as-synthesized monolayers show high phase purity crystallinity. optical electrical performance of these materials comparable those synthesized at higher temperatures. We believe work will accelerate industrial semiconducting
We report on the electrochemical charge storage behavior of few-layered flakes molybdenum disulfide (MoS2) obtained by liquid phase exfoliation bulk MoS2 powder in 1-dodecyl-2-pyrrolidinone. The specific capacitances exfoliated using a 6 M KOH aqueous solution as an electrolyte were found to be order magnitude higher than those (∼0.5 and ∼2 mF cm(-2) for electrodes, respectively). also showed significant different electrolytes, such organic solvents [1 tetraethylammonium tetrafluoroborate...
We experimentally demonstrate single beam directional perfect absorption (to within experimental accuracy) of p-polarized light in the near-infrared using unpatterned, deep subwavelength films indium tin oxide (ITO) on Ag. The occurs slightly above epsilon-near-zero (ENZ) frequency ITO where permittivity is less than one. Remarkably, we obtain for whose thickness as low ~1/50th operating free-space wavelength and pass attenuation only ~ 5%. further derive simple analytical conditions...
Two-dimensional (2D) transition metal dichalcogenides (TMDCs) have attracted great attention due to their physical and chemical properties that make them promising in electronics optoelectronics. Because of the difficulties controlling concentrations solid precursors spatially nonuniform growth dynamics, it is challenging grow 2D TMDCs over large areas with good uniformity reproducibility so far, which significantly hinders practical use. Here we report a vertical vapor deposition (VCVD)...
Large-area Si-doped graphene (SiG) is controllably synthesized for the first time. A much-enhanced molecular-sensing performance achieved when SiG used as a probing surface. This will open up opportunities developing high-performance sensors that are able to detect trace amounts of organic and fluorescent molecules. Furthermore, many fascinating properties predicted by theoretical calculations can be tested based on as-synthesized SiG.
Contrary to conventional wisdom that light bends away from the normal at interface when it passes high low refractive index media, here we demonstrate an exotic phenomenon direction of electromagnetic power towards is incident arbitrary medium \epsilon-near-zero metamaterial. Moreover, transmitted beam close for all angles incidence. In other words, coming different directions in air or can be redirected almost parallel upon entering This counterintuitive behavior described by Snell's law...