Preparation and Optical Properties of CuS Nanofilms by a Facile Two-Step Process

CuS nanofilms were prepared by a facile two-step process including chemical bath deposition of Cu nanofilms first and the subsequent thermal sulfuration step. The composition and structure of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and Raman spectroscopy. The optical properties of CuS nanofilms were determined by Ultraviolet-visible (UV-Vis) technique. The results show that the nanofilms composed by Cu spherical nanoparticles were completely transformed to the nanofilms composed by CuS nanosheets when the sulfuration temperature was 350[Formula: see text]C. The light absorption edges of CuS nanofilms exhibit red shift when sulfuration occurred at lower temperature. A plausible growth mechanism related with gas phase reaction for formation of CuS nanofilms was also proposed.

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Chemical Vapor Functionalization of ZnO Nanocrystals

MRS Proceedings ◽

10.1557/proc-1260-t01-05 ◽

2010 ◽

Vol 1260 ◽

Cited By ~ 1

Author(s):

Moazzam Ali ◽

Marty D. Donakowski ◽

Markus Winterer

Keyword(s):

Gas Phase ◽

Diffuse Reflectance ◽

Chemical Vapor ◽

X Ray Diffraction ◽

X Ray ◽

Zno Nanocrystals ◽

In Series ◽

Lower Temperature ◽

Diffuse Reflectance Infrared

AbstractChemical Vapor Functionalization (CVF) is a method in which nanocrystals undergo in situ functionalization in the gas phase. In CVF, two reactors are used in series. The first reactor consists of a hot quartz tube (1073 K) where ZnO nanocrystals are synthesized in the gas phase from diethylzinc and oxygen. The second reactor, connected at the exit of the first one and kept at lower temperature (673 K), is used as functionalization chamber. At the connecting point of the two reactors, vapors of organic functionalizing agents are injected which react with the surface of ZnO nanocrystals. ZnO nanocrystals have been functionalized by 1-hexanol, n-hexanoic acid, n-hexanal and 1-hexylamine. Functionalized ZnO nanocrystals have been characterized by Dynamic Light Scattering, X-ray Diffraction and Diffuse Reflectance Infrared Fourier Transform Spectroscopy.

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Photodimerization of anthracene single crystals in situ in the electron microscope

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1971.0126 ◽

1971 ◽

Vol 324 (1556) ◽

pp. 37-43 ◽

Cited By ~ 10

Keyword(s):

Electron Microscope ◽

Gas Phase ◽

Mercury Vapour ◽

Phase Reaction ◽

X Ray Diffraction ◽

X Ray ◽

Mercury Vapour Lamp ◽

Diffraction Patterns ◽

Rule Out

Thin (001) plates of pure anthracene (≈ 50 nm thick in the c* direction) have been dimerized in situ in an electron microscope at approximately —100 °C by irradiating them with the 366 nm line from a mercury vapour lamp. Selected-area diffraction patterns and the corresponding bright-held micrographs show that the dianthracene forms in one of the topotactic relationships with the original anthracene encountered in X -ray diffraction studies (O’Donnell 1968), i. e. [010] A ||[010] D and [102] A ||[001] D . Crystallites of dianthracene ≈ 10 nm in diameter are formed and the photographs appear to rule out both a gas phase reaction and any kind of cooperative phenomenon involving an intermediate conversion of strings or sheets of molecules preceding final recrystallization, as found for anthracene photo-oxide (Lonsdale, Nave & Stephens 1966).

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Preparation of ZrO2 Spherical Nanoparticles Used for Photonic Crystal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.412.57 ◽

2011 ◽

Vol 412 ◽

pp. 57-60 ◽

Cited By ~ 1

Author(s):

Xiao Qiang Wang ◽

Meng Wang ◽

Xiao Yan Zhu ◽

Ming Ya Li

Keyword(s):

Photonic Crystal ◽

Sol Gel ◽

Three Dimensional ◽

Phase Reaction ◽

Size Distributions ◽

Spherical Nanoparticles ◽

X Ray Diffraction ◽

X Ray ◽

Pore Size Distributions ◽

Structure Morphology

ZrO2 spherical nanoparticles were prepared by rheological phase reaction. The crystal structure, morphology and formation mechanism were characterized with X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR) and scanning electron microscopy (SEM), etc. Then three-dimensional photonic crystal was synthesized by sol-gel method and using surfactant as template. The study showed that well-controlled spherical particle is helpful to preparation of photonic crystal with adjustable apertures. Mesoporous ZrO2 was obtained with narrow pore size distributions.

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Structural and optical properties of Tin Oxide and Indium doped SnO2 thin films deposited by thermal evaporation technique

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v12i3.45 ◽

2016 ◽

Vol 12 (3) ◽

pp. 4394-4399

Author(s):

Sura Ali Noaman ◽

Rashid Owaid Kadhim ◽

Saleem Azara Hussain

Keyword(s):

Thin Films ◽

Optical Properties ◽

Tin Oxide ◽

Thermal Evaporation ◽

Pure Sno2 ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

X Ray ◽

Evaporation Technique ◽

Sno2 Thin Films

Tin Oxide and Indium doped Tin Oxide (SnO2:In) thin films were deposited on glass and SiliconÂ substratesÂ byÂ thermal evaporation technique.Â X-ray diffraction pattern of Â pure SnO2 and SnO2:In thin films annealed at 650oC and the results showedÂ that the structure have tetragonal phase with preferred orientation in (110) plane. AFM studies showed an inhibition of grain growth with increase in indium concentration. SEM studies of pureÂ SnO2 and Â Indium doped tin oxide (SnO2:In) ) thin films showed that the films with regular distribution of particles and they have spherical shape.Â Optical properties such asÂ Transmission , optical band-gap have been measured and calculated.

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Prediction of Alkanolamine pKa Values by Combined Molecular Dynamics Free Energy Simulations and ab initio Calculations

10.26434/chemrxiv.11215025 ◽

2019 ◽

Author(s):

Javad Noroozi ◽

William Smith

Keyword(s):

Molecular Dynamics ◽

Free Energy ◽

Ab Initio Calculations ◽

Gas Phase ◽

Quantum Chemical ◽

Phase Reaction ◽

Pka Values ◽

Gas Phase Reaction ◽

Reaction Free Energy ◽

Energy Simulations

We use molecular dynamics free energy simulations in conjunction with quantum chemical calculations of gas phase reaction free energy to predict alkanolamines pka values. <br>

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Study on the Electrical, Structural, Chemical and Optical Properties of PVD Ta(N) Films Deposited with Different N2 Flow Rates

Coatings ◽

10.3390/coatings11080937 ◽

2021 ◽

Vol 11 (8) ◽

pp. 937

Author(s):

Yingying Hu ◽

Md Rasadujjaman ◽

Yanrong Wang ◽

Jing Zhang ◽

Jiang Yan ◽

...

Keyword(s):

Crystal Structure ◽

Optical Properties ◽

Photoelectron Spectroscopy ◽

Crystal Size ◽

Silicon Substrates ◽

X Ray Diffraction ◽

Dc Magnetron Sputtering ◽

Flow Rates ◽

X Ray ◽

N2 Flow Rate

By reactive DC magnetron sputtering from a pure Ta target onto silicon substrates, Ta(N) films were prepared with different N2 flow rates of 0, 12, 17, 25, 38, and 58 sccm. The effects of N2 flow rate on the electrical properties, crystal structure, elemental composition, and optical properties of Ta(N) were studied. These properties were characterized by the four-probe method, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and spectroscopic ellipsometry (SE). Results show that the deposition rate decreases with an increase of N2 flows. Furthermore, as resistivity increases, the crystal size decreases, the crystal structure transitions from β-Ta to TaN(111), and finally becomes the N-rich phase Ta3N5(130, 040). Studying the optical properties, it is found that there are differences in the refractive index (n) and extinction coefficient (k) of Ta(N) with different thicknesses and different N2 flow rates, depending on the crystal size and crystal phase structure.

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Metabolic alteration of Methylococcus capsulatus str. Bath during a microbial gas-phase reaction

Bioresource Technology ◽

10.1016/j.biortech.2021.125002 ◽

2021 ◽

Vol 330 ◽

pp. 125002

Author(s):

Yan-Yu Chen ◽

Yuki Soma ◽

Masahito Ishikawa ◽

Masatomo Takahashi ◽

Yoshihiro Izumi ◽

...

Keyword(s):

Gas Phase ◽

Phase Reaction ◽

Methylococcus Capsulatus ◽

Gas Phase Reaction ◽

Metabolic Alteration

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Transport and Dielectric Properties of Mechanosynthesized La2/3Cu3Ti4O12 Ceramics

Crystals ◽

10.3390/cryst11030313 ◽

2021 ◽

Vol 11 (3) ◽

pp. 313

Author(s):

Mohamad M. Ahmad ◽

Hicham Mahfoz Kotb ◽

Celin Joseph ◽

Shalendra Kumar ◽

Adil Alshoaibi

Keyword(s):

Dielectric Constant ◽

Sintering Temperature ◽

Cubic Phase ◽

X Ray Diffraction ◽

Boundary Conductivity ◽

X Ray ◽

Giant Dielectric ◽

Mechanochemical Milling ◽

Giant Dielectric Constant ◽

Lower Temperature

La2/3Cu3Ti4O12 (LCTO) powder has been synthesized by the mechanochemical milling technique. The pelletized powder was conventionally sintered for 10 h at a temperature range of 975–1025 °C, which is a lower temperature process compared to the standard solid-state reaction. X-ray diffraction analysis revealed a cubic phase for the current LCTO ceramics. The grain size of the sintered ceramics was found to increase from 1.5 ± 0.5 to 2.3 ± 0.5 μm with an increase in sintering temperature from 975 to 1025 °C. The impedance results show that the grain conductivity is more than three orders of magnitude larger than the grain boundary conductivity for LCTO ceramics. All the samples showed a giant dielectric constant (1.7 × 103–3.4 × 103) and dielectric loss (0.09–0.17) at 300 K and 10 kHz. The giant dielectric constant of the current samples was attributed to the effect of internal barrier layer capacitances due to their electrically inhomogeneous structure.

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