Search results for "INTERFACE"
showing 10 items of 2139 documents
Metal-organic chemical vapor deposition of Cr2O3 and Nd2O3 coatings. Oxide growth kinetics and characterization
2000
Thin oxide films of Cr2O3 and Nd2O3 were prepared, using Metal-Organic Chemical Vapor Deposition (MOCVD) technique, to protect stainless steels against corrosion at high temperature. The conditions of precursor volatilization were studied by thermogravimetry. Deposited film growth kinetics depended on the deposition parameters, particularly substrate temperature, gas flow rate and location of substrate in the coating reactor. The influence of the deposition parameters on the deposition rate and the uniformity of the films is discussed. The oxide films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and atomic force mi…
A combined computational and experimental study on the mild steel corrosion inhibition in hydrochloric acid by new multifunctional phosphonic acid co…
2020
Two triazole derivatives with phosphonic acid as pendent group, namely [3-(4-phenyl-[1–3]triazol-1-yl)-propyl]-phosphonicaciddiethylester (PTP) and [3-[4-(4-dimethylamino-phenyl)-[1–3]triazol-1-yl]-propyl]-phosphonic acid diethylester (DMPTP) were synthesized and fully characterized using NMR spectroscopy, Mass spectrometry, Infra-Red (FT-IR) spectroscopy and elemental analysis. The synthesized multifunctional heterocycles were investigated to inhibit the corrosion of mild steel in acidic solution HCl (1 M) by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP) and weight loss measurements. The results of the different corrosion measurement techniques are in goo…
In situ diagnostics and control of laser-induced removal of iron oxide layers
2002
The mechanism of laser-induced removal of thermally grown iron oxide layers on pure iron has been investigated by means of in situ reflectivity measurements. The experiments were carried out by irradiating the sample with λ=584 nm, τ=6 ns (FWHM) laser pulses in a buffer borate solution after a cathodic polarisation of - 1.5 V/SCE had been applied during 40 min. The removal efficiency has been studied as a function of the number of laser pulses, for several fluence values and for a few time delays after switching off the cathodic polarisation. The results demonstrate that reflectivity measurements are a suitable non-invasive in situ diagnostics tool for the assessment of the efficiency of ox…
Correlated effects of fluorine and hydrogen in fluorinated tin oxide (FTO) transparent electrodes deposited by sputtering at room temperature
2021
The optical and electrical properties of fluorinated tin oxide (FTO) films deposited at room temperature by sputtering have been investigated varying the fluorine content and the hydrogen atmosphere. The complex behavior of the obtained films is disclosed using a wide set of characterization techniques that reveals the combined effects of these two parameters on the generated defects. These defects control the electrical transport (carrier density, mobility and conductivity), the optical properties (band gap and defects-related absorption and photoluminescence) and finally promote the amorphization of the samples. H2 in the sputtering gas does not modify the H content in the films but induc…
DFT studies of OH-functionalized open-ended zigzag, armchair, and chiral single wall carbon nanotubes
2011
The functionalization of single-wall carbon nanotubes (SWCNTs) by attaching various molecules or molecular groups to the exterior walls or tips has attracted much attention, because it offers a possible way to modify their electronic, chemical, optical and mechanical properties. In this contribution the results of DFT studies of pristine and OH-modified open-ended zigzag (9,0), armchair (5,5) and chiral (8,2) nanotubes are reported. The calculations have been performed for partially and fully functionalized at one end model SWCNTs with dangling bonds saturated with hydrogen atoms and a nonadditive dependence of attachment energy on the number of substituents was observed.
The commensurate-incommensurate transition of hydrogen monolayers physisorbed on graphite
1987
We present a neutron diffraction study of the commensurate-incommensurate (C-IC) transition of hydrogen monolayers physisorbed on the basal planes of exfoliated graphite. It is shown that the solid intermediate phase detected by specific-heat measurements can be described in terms of a striped domain-wall phase with superheavy walls. Comparison with simple models with fixed domain sizes is made. The results are in agreement with recent LEED experiments of Cui and Fain and provide an experimental realization of C-IC transition theories.
Pulsed laser cleaning of oxidized metallic surfaces in electrochemically controlled liquid confinement
1997
Pulsed laser cleaning of oxidized metallic surfaces is studied. To our knowledge, for the first time, it has been demonstrated that the application of pulsed laser irradiation in a liquid confinement at controlled electrochemical potential enhances the oxide film removal from metal surfaces. Systematic studies on simulated corrosion product films using optical reflectance profile, energy dispersive X-ray spectroscopy, and piezoelectric transducer measurements, have revealed that efficient oxide film removal by laser irradiation is achieved if a basic electrolyte solution is used and a cathodic potential is imposed. The advantages of this novel technique against laser irradiation in air are …
Properties of AlN grown by plasma enhanced atomic layer deposition
2011
Abstract The influence of growth parameters on the properties of AlN films fabricated by plasma-enhanced atomic layer deposition using trimethylaluminum and ammonia precursors was investigated. The atomic concentrations, refractive index, mass density, crystallinity and surface roughness were studied from the films grown in the temperature range of 100–300 °C with plasma discharge times between 2.5 and 30 s. The AlN films were shown to be hydrogen rich having H concentrations in the range of 13–27 at.% with inverse dependence on the growth temperature. The carbon and oxygen concentrations in the films were less than 2.6% and 0.2%, respectively. The refractive index and mass density of the f…
Dual Ni/Ni-Co electrodeposited coatings for improved erosion-corrosion behaviour
2019
Abstract Industrial applications of hydrophobic metallic coatings are limited to durability of their surface structures against detrimental effects of the surrounding environments. In the present research, the life-long of the hierarchical structure of hydrophobic nickel coating in an erosive-corrosive solution was investigated. The effect of alloying with cobalt on strengthening the hierarchical structures was also investigated. In this regard, highly hydrophobic Ni/Ni, Ni-Co/Ni-Co, dual Ni/Ni-Co and dual Ni-Co/Ni coatings with rough hierarchical structures were electrodeposited. In situ electrochemical measurements were performed to investigate changes in corrosion resistance and hydropho…
Spatially resolved nanostructural transformation in graphite under femtosecond laser irradiation
2015
Abstract A polycrystalline graphite target was irradiated using infrared (800 nm) femtosecond (120 fs) laser pulses of different energies. Increase of sp 3 bonds percentage and possible diamond crystal formation were investigated ‘in-depth’ and on the irradiated surfaces. Synchrotron X-ray diffraction pattern have shown the presence of a diamond peak in one of the irradiated zones while X-ray photoelectron spectroscopy investigations have shown an increasing tendency of the sp 3 percent in the low power irradiated areas and similarly ‘in the depth’ of the higher power irradiated zones. Multiple wavelength Micro-Raman investigations have confirmed this trend along with an ‘in-depth’ (but not…