Microscopic Origin of the Apparent Activation Energy in Diffusion-Mediated Monolayer Growth of Two-Dimensional Materials

Hydrothermally synthesized one-dimensional and two-dimensional nanocrystals of VO2 undergo phase transition around 65?C, where temperature and mechanism of phase transition are dependent on dimensionality of nanocrystals. Both nanocrystalline samples exhibit depression of phase transition temperature compared to the bulk material, the magnitude of which depends on the dimensionality of the nanocrystal. One-dimensional nanoribbons exhibit lower phase transition temperature and higher values of apparent activation energy than two-dimensional nanosheets. The phase transition exhibits as a complex process with somewhat lower value of enthalpy than the phase transition in the bulk, probably due to higher proportion of surface atoms in the nanocrystals. High values of apparent activation energy indicate that individual steps of the phase transition involve simultaneous movement of large groups of atoms, as expected for single-domain nanocrystalline materials.

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Dominant contributions to the apparent activation energy in two-dimensional submonolayer growth: comparison between Cu/Ni(111) and Ni/Cu(111)

Journal of Physics Condensed Matter ◽

10.1088/1361-648x/ab9b50 ◽

2020 ◽

Vol 32 (44) ◽

pp. 445002

Author(s):

Joseba Alberdi-Rodriguez ◽

Shree Ram Acharya ◽

Talat S Rahman ◽

Andres Arnau ◽

Miguel A Gosálvez

Keyword(s):

Activation Energy ◽

Apparent Activation Energy ◽

Two Dimensional

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Influence of B2O3 on viscosity and structure of low MgO slag containing titanium

Metallurgical Research & Technology ◽

10.1051/metal/2017103 ◽

2018 ◽

Vol 115 (3) ◽

pp. 313 ◽

Cited By ~ 3

Author(s):

Xiaoyue Fan ◽

Jianliang Zhang ◽

Kexin Jiao ◽

Renze Xu ◽

Kaidi Wang

Keyword(s):

Activation Energy ◽

Raman Spectroscopy ◽

Apparent Activation Energy ◽

Turning Point ◽

Degree Of Polymerization ◽

Viscous Resistance ◽

Two Dimensional ◽

Network Modifier ◽

Low Strength

The viscous behavior of CaO–SiO2–15.2 wt% Al2O3–4.8 wt% MgO–TiO2–B2O3 slags is studied. The effect of the TiO2 and B2O3 on the viscosity and apparent activation energy, as well as the effect of B2O3 on structure is investigated through Raman spectroscopy. The viscosity and apparent activation energy of CaO–SiO2–15.2 wt% Al2O3–4.8 wt% MgO–TiO2 are decreased with increased TiO2 content, which can be explained by the network modifier role that TiO2 acts in slags. The addition of B2O3 can reduce the viscosity of CaO–SiO2–15.2 wt% Al2O3–4.8 wt% MgO–TiO2–B2O3 slags, and it brings about a turning point on apparent activation energy curves. Raman spectroscopy shows that B2O3 acts as acidic oxide and increases the degree of polymerization of slags. However, with the addition of B2O3, the appearance of two dimensional [BO3] structure units and the low strength energy of B–O bonds can reduce the viscous resistance in molten slags and decrease the viscosity.

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A probability density function for polycrystalline two-dimensional materials

10.26226/morressier.5f5f8e69aa777f8ba5bd5f8d ◽

2020 ◽

Author(s):

Christopher Samuel DiMarco

Keyword(s):

Probability Density Function ◽

Probability Density ◽

Density Function ◽

Two Dimensional ◽

Two Dimensional Materials

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Redox-Active Approach Towards New Magnetic And Conductive Two-Dimensional Materials

10.31988/scitrends.41652 ◽

2018 ◽

Author(s):

Penny Perlepe ◽

Rodolphe Clérac ◽

Itziar Oyarzabal ◽

Corine Mathonière

Keyword(s):

Two Dimensional ◽

Active Approach ◽

Redox Active ◽

Two Dimensional Materials

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Polarization-sensitive photodetectors based on three-dimensional molybdenum disulfide (MoS2) field-effect transistors

Nanophotonics ◽

10.1515/nanoph-2020-0401 ◽

2020 ◽

Vol 9 (16) ◽

pp. 4719-4728

Author(s):

Tao Deng ◽

Shasha Li ◽

Yuning Li ◽

Yang Zhang ◽

Jingye Sun ◽

...

Keyword(s):

Molybdenum Disulfide ◽

Field Effect ◽

High Performance ◽

Field Effect Transistors ◽

Three Dimensional ◽

Polarized Light ◽

Optical Field ◽

Two Dimensional ◽

Polarization Ratio ◽

Two Dimensional Materials

AbstractThe molybdenum disulfide (MoS2)-based photodetectors are facing two challenges: the insensitivity to polarized light and the low photoresponsivity. Herein, three-dimensional (3D) field-effect transistors (FETs) based on monolayer MoS2 were fabricated by applying a self–rolled-up technique. The unique microtubular structure makes 3D MoS2 FETs become polarization sensitive. Moreover, the microtubular structure not only offers a natural resonant microcavity to enhance the optical field inside but also increases the light-MoS2 interaction area, resulting in a higher photoresponsivity. Photoresponsivities as high as 23.8 and 2.9 A/W at 395 and 660 nm, respectively, and a comparable polarization ratio of 1.64 were obtained. The fabrication technique of the 3D MoS2 FET could be transferred to other two-dimensional materials, which is very promising for high-performance polarization-sensitive optical and optoelectronic applications.

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