scholarly journals CoCrFeNi High-Entropy Alloy Thin Films Synthesised by Magnetron Sputter Deposition from Spark Plasma Sintered Targets

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 468
Author(s):  
Holger Schwarz ◽  
Thomas Uhlig ◽  
Niels Rösch ◽  
Thomas Lindner ◽  
Fabian Ganss ◽  
...  
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Atomic Ratio ◽  
Economic Benefits ◽  
High Entropy Alloy ◽  
X Ray ◽  
High Entropy ◽  
Magnetron Sputter Deposition ◽  
Spark Plasma ◽  
Magnetron Sputter

Two magnetron sputter targets of CoCrFeNi High-Entropy Alloy (HEA), both in equal atomic ratio, were prepared by spark plasma sintering. One of the targets was fabricated from a homogeneous HEA powder produced via gas atomisation; for the second target, a mixture of pure element powders was used. Economic benefits can be achieved by mixing pure powders in the intended ratio in comparison to the gas atomisation of the specific alloy composition. In this work, thin films deposited via magnetron sputtering from both targets are analysed. The surface elemental composition is investigated by X-ray photoelectron spectroscopy, whereas the bulk stoichiometry is measured by X-ray fluorescence spectroscopy. Phase information and surface microstructure are investigated using X-ray diffraction and scanning electron microscopy, respectively. It is demonstrated that the stoichiometry, phase composition and microscopic structure of the as-deposited HEA thin films are almost identical if the same deposition parameters are used.

Stoichiometric Controlling of Spark Plasma Sintered Boron-Carbon Ceramics

2009 ◽  
Vol 66 ◽  
pp. 25-28 ◽  
Author(s):  
Song Zhang ◽  
Chuan Bin Wang ◽  
Qiang Shen ◽  
Lian Meng Zhang
Keyword(s):  
Photoelectron Spectroscopy ◽  
Measurement Data ◽  
Atomic Ratio ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Carbon Ceramic ◽  
Boron Carbon

A group of boron-carbon ceramic material was in-situ synthesized and densified simultaneously via Spark Plasma Sintering (SPS) technique from carbon and boron element powders with different molar ratio. The phase structures of samples with different B/C molar ratio were characterized by X-ray Diffraction (XRD). The B/C atomic ratio of the sintered materials was calculated from X-ray photoelectron spectroscopy (XPS) measurement data. Meanwhile, the chemical analysis (CA) method had also been taken to verify the B/C atomic ratio. Finally, the experience equation had been obtained to control the B/C atomic ratio of sintered samples.

EFFECT OF ANNEALING AND SnO2 ADDITION ON PROPERTIES OF NANOSTRUCTURED ZnO THIN FILMS

2011 ◽  
Vol 10 (04n05) ◽  
pp. 1007-1011
Author(s):  
VIPIN KUMAR JAIN ◽  
PRAVEEN KUMAR ◽  
DEEPIKA BHANDARI ◽  
Y. K. VIJAY
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
Atomic Ratio ◽  
Flash Evaporation ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Post Annealing ◽  
Zinc Tin Oxide ◽  
Evaporation Technique

In the present work, Zinc–Tin–Oxide (ZTO) thin films were deposited on glass substrate with varying concentration ( ZnO:SnO2 -100:0, 90:10, 70:30 and 50:50 wt.%) at room temperature by flash evaporation technique. These deposited ZTO film were annealed in vacuum to study the thermal stability and to see the effects on the structural and optical properties. The XRF spectra revealed the presence of Zinc and Tin with varying concentration in ZTO thin films. XRD results show the crystallinity of the ZTO films was improved with increasing the concentration of SnO2 and post annealing. The surface composition and oxidation state were analyzed by X-ray photoelectron spectroscopy. The variation of % composition shows as the concentration of SnO2 increases from 0 to 50%, the atomic ratio of Sn/Zn and O/Zn increases for both types of ZTO films and deficiency of oxygen has been appeared after annealing. The optical band gap was also found to be decreased for both types of films with increasing concentration of SnO2 .

Nanostructure evolution and properties of two-phase nc-Ti(C, N)/a-(C, CNx) nanocomposites by high-resolution transmission electron microscopy, x-ray photoelectron spectroscopy, and Raman spectroscopy

2007 ◽  
Vol 22 (9) ◽  
pp. 2460-2469 ◽  
Author(s):  
Y.H. Lu ◽  
Y.G. Shen
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Solid Solution ◽  
Transmission Electron Microscopy ◽  
Raman Spectroscopy ◽  
Photoelectron Spectroscopy ◽  
Atomic Ratio ◽  
Two Phase ◽  
X Ray ◽  
Transmission Electron

High-resolution transmission electron microscopy, x-ray photoelectron spectroscopy (XPS), and Raman spectroscopy were used to study phase configuration and nanostructure evolutions of Ti–Cx–Ny thin films with different amounts of C incorporation. It was found that the atomic ratio of (C + N)/Ti played a crucial role in phase configuration and nanostructure evolutions as well as mechanical behaviors. When the ratio was less than one unit, a nanocrystalline (nc-) Ti(C, N) solid solution was formed by way of dissolution of C into TiN lattice. When this dissolution reached saturation, precipitation of a small amount of amorphous (a-) C phase along nc-Ti(C, N) grains was followed with more C incorporation. Further increase of C content (up to ∼19 at.% C) made the amorphous phase fully wet nanocrystallites, which resulted in the formation of two-phase nanocomposite thin films with microstructures comprising of ∼5 nm nc-Ti(C,N) crystallites separated by ∼0.5 nm a-(C, CNx) phase. Thicker amorphous walls and smaller sized grains were followed when the C content was further increased, accompanying with the formation of some disorders and defects in nc-grains and amorphous matrices. When the C content was increased to ∼48 at.%, 1–3 nm nanocrystallites with an average size of ∼2 nm were embedded into amorphous matrices. Both microhardness and residual compressive stress values were increased with increase of the atomic ratio in solid solution thin films when the atomic ratio value was less than one unit. Their maximums were obtained at stiochiometry nc-Ti(C,N) solid solution. Enhancement of hardness values was attributed to solid solution effect.

scholarly journals Laser-generated high entropy metallic glass nanoparticles as bifunctional electrocatalysts

Nano Research ◽  
2021 ◽  
Author(s):  
Jacob Johny ◽  
Yao Li ◽  
Marius Kamp ◽  
Oleg Prymak ◽  
Shun-Xing Liang ◽  
...  
Keyword(s):  
Metallic Glass ◽  
Energy Conversion ◽  
Photoelectron Spectroscopy ◽  
Surface Segregation ◽  
Amorphous Structure ◽  
High Entropy Alloy ◽  
Elemental Distribution ◽  
X Ray ◽  
High Entropy ◽  
Depth Analysis

AbstractHigh entropy metallic glass nanoparticles (HEMG NPs) are very promising materials for energy conversion due to the wide tuning possibilities of electrochemical potentials offered by their multimetallic character combined with an amorphous structure. Up until now, the generation of these HEMG NPs involved tedious synthesis procedures where the generated particles were only available on highly specialized supports, which limited their widespread use. Hence, more flexible synthetic approaches to obtain colloidal HEMG NPs for applications in energy conversion and storage are highly desirable. We utilized pulsed laser ablation of bulk high entropy alloy targets in acetonitrile to generate colloidal carbon-coated CrCoFeNiMn and CrCoFeNiMnMo HEMG NPs. An in-depth analysis of the structure and elemental distribution of the obtained nanoparticles down to single-particle levels using advanced transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) methods revealed amorphous quinary and senary alloy phases with slight manganese oxide/hydroxide surface segregation, which were stabilized within graphitic shells. Studies on the catalytic activity of the corresponding carbon-HEMG NPs during oxygen evolution and oxygen reduction reactions revealed an elevated activity upon the incorporation of moderate amounts of Mo into the amorphous alloy, probably due to the defect generation by atomic size mismatch. Furthermore, we demonstrate the superiority of these carbon-HEMG NPs over their crystalline analogies and highlight the suitability of these amorphous multi-elemental NPs in electrocatalytic energy conversion.

scholarly journals Fabrication and Characterization of Transparent and Scratch-Proof Yttrium/Sialon Thin Films

Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2283
Author(s):  
Amar Kamal Mohamedkhair ◽  
Abbas Saeed Hakeem ◽  
Qasem Ahmed Drmosh ◽  
Abdul Samad Mohammed ◽  
Mirza Murtuza Ali Baig ◽  
...  
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Scratch Test ◽  
Xrd Analysis ◽  
Inert Atmosphere ◽  
X Ray ◽  
Β Phase ◽  
Plasma Sintering ◽  
Vis Spectroscopy ◽  
Spark Plasma

Transparent and amorphous yttrium (Y)/Sialon thin films were successfully fabricated using pulsed laser deposition (PLD). The thin films were fabricated in three steps. First, Y/Sialon target was synthesized using spark plasma sintering technique at 1500 °C in an inert atmosphere. Second, the surface of the fabricated target was cleaned by grinding and polishing to remove any contamination, such as graphite and characterized. Finally, thin films were grown using PLD in an inert atmosphere at various substrate temperatures (RT to 500 °C). While the X-ray diffractometer (XRD) analysis revealed that the Y/Sialon target has β phase, the XRD of the fabricated films showed no diffraction peaks and thus confirming the amorphous nature of fabricated thin films. XRD analysis displayed that the fabricated thin films were amorphous while the transparency, measured by UV-vis spectroscopy, of the films, decreased with increasing substrate temperature, which was attributed to a change in film thickness with deposition temperature. X-ray photoelectron spectroscopy (XPS) results suggested that the synthesized Y/Sialon thin films are nearly homogenous and contained all target’s elements. A scratch test revealed that both 300 and 500 °C coatings possess the tough and robust nature of the film, which can resist much harsh loads and shocks. These results pave the way to fabricate different Sialon doped materials for numerous applications.

Nanoscaled C, Ni, Pt Thin Films

2009 ◽  
Vol 6 ◽  
pp. 29-34
Author(s):  
Wan Yu Wu ◽  
Chia Wei Hsu ◽  
Jyh Ming Ting
Keyword(s):  
Thin Films ◽  
Raman Spectroscopy ◽  
Sputter Deposition ◽  
Deposition Technique ◽  
Electrical And Optical Properties ◽  
Ir Spectrometry ◽  
X Ray ◽  
Magnetron Sputter Deposition ◽  
Magnetron Sputter ◽  
Quartz Substrates

We have investigated the growth and characteristics of nanoscaled thin films of carbon, nickel, and platinum. The nanoscaled thin films were deposited on Si and quartz substrates with or without a surface layer of carbon, nickel, or platinum using a DC magnetron sputter deposition technique. The thicknesses, which were determined using ellipsometry, are all less than 10 nm. The film structures were examined using glazing angle incident x-ray diffractometry and Raman spectroscopy. The electrical and optical properties were determined using a four point probe technique and UV-VIS-IR spectrometry, respectively.

Preparation and Characterization of Cd1-xZnxS Thin Films with Chemical Bath Deposition

2015 ◽  
Vol 1088 ◽  
pp. 86-90
Author(s):  
Li Mei Zhou ◽  
Yun Long Li ◽  
Yue Jie Dong
Keyword(s):  
Thin Films ◽  
Chemical Bath Deposition ◽  
Photoelectron Spectroscopy ◽  
Measurement Instrument ◽  
Soda Lime ◽  
Atomic Ratio ◽  
Visible Range ◽  
Soda Lime Glass ◽  
Height Measurement ◽  
X Ray

Cd1-xZnxS thin films were grown on soda-lime glass substrates by chemical-bath deposition (CBD). The surface morphology, thickness, composition, state of the constituent elements and optical properties of the films were studied with X-ray diffraction (XRD), scanning electron microscopy (SEM), step height measurement instrument, X-ray photoelectron spectroscopy (XPS) and spectrophotometer, respectively. The affect of annealing for the Cd1-xZnxS thin films was studied. The Cd1-xZnxS thin films had cubic crystal structure and the average transmittance was 86.8% in the visible range with the optical band gap of 2.61eV and the films thickness was about 50nm. The atomic ratio of (Cd + Zn): S increased after annealing.

Elemental Distribution in CrNbTaTiW-C High Entropy Alloy Thin Films

2019 ◽  
Vol 25 (2) ◽  
pp. 489-500 ◽  
Author(s):  
Deodatta Shinde ◽  
Stefan Fritze ◽  
Mattias Thuvander ◽  
Paulius Malinovskis ◽  
Lars Riekehr ◽  
...  
Keyword(s):  
Thin Films ◽  
Formation Enthalpy ◽  
Amorphous Film ◽  
Atom Probe ◽  
Amorphous Structure ◽  
High Entropy Alloy ◽  
Elemental Distribution ◽  
X Ray ◽  
High Entropy ◽  
Strong Segregation

AbstractThe microstructure and distribution of the elements have been studied in thin films of a near-equimolar CrNbTaTiW high entropy alloy (HEA) and films with 8 at.% carbon added to the alloy. The films were deposited by magnetron sputtering at 300°C. X-ray diffraction shows that the near-equimolar metallic film crystallizes in a single-phase body centered cubic (bcc) structure with a strong (110) texture. However, more detailed analyses with transmission electron microscopy (TEM) and atom probe tomography (APT) show a strong segregation of Ti to the grain boundaries forming a very thin Ti–Cr rich interfacial layer. The effect can be explained by the large negative formation enthalpy of Ti–Cr compounds and shows that CrNbTaTiW is not a true HEA at lower temperatures. The addition of 8 at.% carbon leads to the formation of an amorphous structure, which can be explained by the limited solubility of carbon in bcc alloys. TEM energy-dispersive X-ray spectroscopy indicated that all metallic elements are randomly distributed in the film. The APT investigation, however, revealed that carbide-like clusters are present in the amorphous film.

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