bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distribution of intercalated lithium in V2O5 thin films determined by SIMS depth profiling
Authors: Alamarguy D. , Castle J. E. , Liberatore M. , Decker F. 
Published: March 2006

AbstractThe distribution of Li in the V2O5 films was determined before and after intercalation/deintercalation electrochemical cycles by time of flight secondary ion mass spectroscopy (ToF‐SIMS) depth profiling. On deintercalation most of the inserted Li is removed except in the vicinity of the interface with the fluorine‐substituted tin oxide, used as a conducting substrate. More surprisingly, Li was also found in the interface region of the part of the film that has not been immersed in the electrolyte and that had thus not been electrochemically controlled. This finding suggests that Li diffuses through the interface, in the plane of the electrode surface, during intercalation of the main body of the film. The SIMS results have been confirmed by proton beam analysis using the nuclear reaction between H and Li to produce characteristic alpha particles that reveal the distribution of Li, both inside and outside the electrochemically treated area of the electrode. The energy loss of the alpha particles on their way through the sample to the detector also reveals the Li concentration distribution inside the V2O5 films. Copyright © 2006 John Wiley & Sons, Ltd.
Recovering the past from surfaces and interfaces: experimental and cultural issues
Authors: Paparazzo E. 
Published: March 2006

AbstractSurface science studies have substantially advanced our knowledge of the physico‐chemical characteristics of archaeomaterials and of the modifications produced on them by their surroundings. In the present paper, some experimental aspects encountered in XPS and AES analyses of archaeomaterials will be reviewed, including some cases for which the surface (of Roman bronze) and the interface (of Roman lead pipes) are themselves a source of archaeological evidence. The views on surfaces, as discussed by philosophers, writers and artists, from antiquity up to this day will then be discussed. It will be shown that the account of Pliny the Elder on the surface oxidation of metal surfaces was influenced by the views of the Stoic philosopher Posidonius, and this will be discussed in the light of XPS and AES spectra recorded on relevant surfaces. Copyright © 2006 John Wiley & Sons, Ltd.
Auger parameter studies of third‐row chemical elements
Authors: Moretti Giuliano , Paparazzo Ernesto 
Published: March 2006

AbstractThe Auger parameter (AP) studies available in the literature are usually based on Auger transitions involving only core‐level electrons. In this paper, besides the usual AP − α*Z = [BE(2p)] + [KE(KL23L23)], (Z = third‐row chemical elements)—we also considered the AP involving core–valence–valence Auger transitions − γ*Z = [BE(2p)] + [KE(L23VV)]. The chemical shifts for γ* between Al0 and Al2O3 and between Si0 and SiO2 are more than twice that for α*, whereas the difference in such chemical shifts progressively decreases with increasing Z. While the inelastic mean free path (λ) associated with α* spans the range ∼2.5–4.5 nm, γ* relates to a much more surface‐specific analysis, i.e. 0.5 < λ < 2.5 nm. We discuss the diagnostic potential of γ* and outline its advantages and shortcomings in the surface and interface analysis of materials. Copyright © 2006 John Wiley & Sons, Ltd.
Influence of the metal nature (Ni, Cu, Mg) on the surface acid–base properties of mixed oxides elaborated from LDH
Authors: Dussault L. , Dupin J. C. , Martinez H. , Dumitriu E. , Auroux A. , Guimon C. 
Published: March 2006

AbstractLamellar double hydroxides with different proportions of Ni, Cu, Mg and Al were prepared and calcined at 723 K to obtain mixed oxides with acid–base and redox properties. The acidic and basic sites of the surface of these catalysts were characterized by adsorption microcalorimetry, XPS coupled with adsorption experiments and catalytic conversion of cyclohexanol. The adsorption experiments were performed with NH3 for the characterization of the acidic sites and with SO2 for that of the basic sites. The acidic sites are relatively weak and heterogeneous and of Lewis type. On the contrary, the basic sites are strong and homogeneous and of Brönsted (mainly) and Lewis type. The acidity and the basicity increase with the ratio Ni/Cu, whereas the basicity decreases with increasing Mg/Al. Copyright © 2006 John Wiley & Sons, Ltd.
Correlation between electrochemical reactivity and surface chemistry of amorphous carbon nitride films
Authors: Cachet H. , Debiemme‐Chouvy C. , Deslouis C. , Lagrini A. , Vivier V. 
Published: March 2006

AbstractAmorphous carbon nitride (a‐CNx) films prepared by RF magnetron sputtering technique display a moderate electrochemical reactivity. However, after electrochemical activation by a cathodic pretreatment in acidic solution, they exhibit a quasimetallic behavior. This behavior has been notably assessed by scanning electrochemical microscopy (SECM). The approach curves show that the a‐CNx electrode surfaces are made of active and inactive domains. These surfaces have also been characterized by atomic force microscopy (AFM) and XPS. AFM shows that the a‐CNx surface roughness remains very low after the activation treatment. XPS analyses indicate that the electrochemical activation of the a‐CNx materials is associated with a decrease in the number of superficial nitrogen atoms involved in sp3 CN bonds. Copyright © 2006 John Wiley & Sons, Ltd.
Comparative study of the corrosion behavior of zinc coatings deposited on low carbon steel substrates
Authors: Pistofidis N. , Vourlias G. , Chaliampalias D. , Pavlidou E. , Stergioudis G. , Polychroniadis E. K. 
Published: March 2006

AbstractThe corrosion behavior of zinc pack coatings was examined with X‐ray diffraction (XRD) and scanning electron microscopy (SEM) and it was compared with the performance of the zinc coatings formed with hot dipping. The examined samples were exposed in a salt spray chamber (SSC) for different periods of time starting from 24 h up to ten days. This investigation showed that the main corrosion products were Zn‐ and Fe‐hydrated chlorides and oxides, while a stress corrosion mechanism controlled the pack corrosion. By contrast, the hot‐dipped coatings are uniformly corroded, while pitting corrosion and internal oxidation are also possible. Copyright © 2006 John Wiley & Sons, Ltd.
Effect of simulated marine atmosphere on tin plasma‐sprayed coatings
Authors: Vourlias G. , Pistofidis N. , Chaliampalias D. , Pavlidou E. , Stergioudis G. , Polychroniadis E. K. , Tsipas D. 
Published: March 2006

AbstractIn the present work, strips of steel St‐37 were coated with Sn using the plasma‐spraying technique. Their corrosion behavior was examined with exposure in a salt spray chamber (SSC) at 40 °C and 100% relative humidity, while the corrosive medium was a 5 wt% NaCl aqueous solution. The exposure time of the samples ranged from 24 h up to 10 days. The as‐corroded samples were studied with optical microscopy, scanning electron microscopy (SEM) and X‐ray diffraction (XRD). Sn and Fe oxides and chlorides were detected on the coating surface along with the formation of large cavities. A possible mechanism of internal oxidation was used to explain these observations. Copyright © 2006 John Wiley & Sons, Ltd.
Surface analyses and depth profiles of oxide scales formed on alloy surface
Authors: Horita Teruhisa , Xiong Yueping , Kishimoto Haruo , Yamaji Katsuhiko , Sakai Natsuko , Brito Manuel E. , Yokokawa Harumi 
Published: March 2006

AbstractThe distributions of elements were analyzed at oxide scale surface and around the oxide scale/alloy interfaces. Glow discharge optical emission spectrometry (GDOES) depth profiles and secondary ion mass spectrometry (SIMS) imaging have been applied to analyze the oxide scales formed on FeCr alloys in CH4H2O (thickness from 100 nm to 4 µm, at 1073 K for 3 to 1050 h). The oxide scale is identified as the following phases from surface to inner oxide: MnFe oxide spinel, Cr2O3 oxide, SiO2, Al2O3 inner oxide and FeCr alloy. The concentration of Si was estimated from the quantitative analysis of Si with the GDOES depth analysis. The Si concentration increases with the oxidation duration and the highest concentration after 1050 h treatment is estimated to be 4.9 mass% from the quantitative analysis of Si. Copyright © 2006 John Wiley & Sons, Ltd.
Surface cleaning of a commercially pure Ti, Ti6Al4V and Ti3Al8V6Cr4Zr4Mo alloys by linear heating
Authors: Dhlamini M. S. , Swart H. C. , Terblans J. J. , Terblanche C. J. 
Published: March 2006

AbstractThe surfaces of Ti and its alloys are always contaminated by O and C due to the continual uptake of the background gases, even in an ultra high vacuum (UHV) chamber. The surfaces of Ti and its alloys (Ti6Al4V and Ti3Al8V6Cr4Zr4Mo) were cleaned by annealing the sample linearly to a temperature higher than 600 °C and then cooled. The segregation of S was only observed after the samples were heated to temperatures above 550 °C. The segregation of S was only measured after most of surface adsorbate elements were removed from the surface. The three samples' surfaces (Ti, Ti6Al4V and Ti3Al8V6Cr4Zr4Mo) were all almost clean or free of contamination in the temperature range 600–650 °C. The addition of the alloying elements impacts the retention of O and C on the surfaces. The linear least square (LLS) fit method was used to determine the contributions of pure Ti, Ti oxide and Ti carbide from the measured Auger peak to peak heights (APPHs). AES peak fitting was done and confirmed the formation of TiC and TiO on the surface at temperatures between 100 °C and 500 °C. The segregation of Al in the Ti6Al4V and Ti3Al8V6Cr4Zr4Mo samples was measured at higher temperatures. Copyright © 2006 John Wiley & Sons, Ltd.
Radio frequency (r.f.) plasma‐deposited polymer films: influence of external plasma parameters as viewed by comprehensive in‐situ surface chemical analysis by XAS, XPS and ToF‐SIMS
Authors: Unger W. E. S. , Swaraj S. , Oran U. , Lippitz A. 
Published: March 2006

AbstractThe formation of plasma‐deposited materials made from organic molecules is a technologically attractive way to obtain films with unique properties, e.g. adhesion, wettability, conductivity or selected chemical functionalization. A detailed chemical characterization of these films is a great challenge for the analyst because of the co‐existence of a large number of chemical species in plasma‐deposited films. We investigated these types of organic films using photoelectron spectroscopy for chemical analysis (ESCA, XPS), near edge X‐ray absorption fine structure (NEXAFS) spectroscopy at synchrotron radiation source BESSY II and time‐of‐flight secondary ion mass spectroscopy (ToF‐SIMS). A dedicated plasma preparation chamber was designed and added to the main analysis chamber of the respective spectrometers. This approach offers the possibility of studying plasma‐deposited films without exposure to air before analysis (often called in‐situ analysis) and the influence of post‐plasma reactions, i.e. the ageing process. The present investigations are aimed at finding correlations between basic chemical properties of the deposited films and the plasma deposition parameters, e.g. duty cycle in pulsed plasmas and the power of discharge. Copyright © 2006 John Wiley & Sons, Ltd.
Nanostructural studies of PVD TiAlB coatings
Authors: Monclus M. A. , Baker M. A. , Rebholz C. , Stolojan V. , Gibson P. N. , Leyland A. , Matthews A. 
Published: March 2006

AbstractTiAlB coatings with different compositions were deposited by co‐sputtering from TiAl and TiB2 targets onto AISI316 stainless steel substrates at a temperature of 170 °C. The stoichiometry and nanostructure have been studied by X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD) and transmission electron microscopy (TEM). Analysis of the XPS spectra suggests the presence of phases in agreement with the equilibrium TiAlB phase diagram. Diffraction studies (XRD and TEM) indicate that coatings with B/Al ratios <6 are amorphous, while coatings with B/Al ratios >6 exhibit a nanocomposite structure with average TiB2 grain sizes of ∼2–3 nm for the highest B/Al ratio of 16. Nanocomposite coatings show significantly improved H/E ratios that are beneficial for protecting soft steels and light alloys. Copyright © 2006 John Wiley & Sons, Ltd.
Friction induced conformational changes on large‐scale and small‐scale polyester sliding surfaces
Authors: Samyn P. , Craenenbroeck J. Van , Quintelier J. , Schoukens G. 
Published: March 2006

AbstractPure and internal PTFE‐lubricated polyesters are slid against steel and stainless steel on large‐scale and small‐scale tribological test rigs under normal loads between 8 and 150 MPa and temperatures of 80–200 °C. The polymer sliding surfaces are analysed by Raman spectra according to a two‐phase system of trans (oriented) and gauche (non‐oriented) structures. Comparing the spectra of pure and internal lubricated polyesters reveals a clear band at 713 cm−1 correlated to PTFE depositions. For small‐scale tests, the crystalline content and overall orientation is larger (40–50%) while no significant increase in the PTFE‐related band is observed. A PTFE/polyester film is transferred onto the steel counterface without back‐transfer to the polymer surface. Large‐scale polymer surfaces have a lower orientation (30–40%) and contradictory to small‐scale samples, PTFE lubricants are observed on the polymer surface. The formation of a PTFE film on the polyester sliding surface is then favourable for low friction and stabilization in wear rates. Orientation and wear effects depend on the movability of wear debris and plastification of the surface, illustrated by Raman spectroscopy. Copyright © 2006 John Wiley & Sons, Ltd.
XPS at solid–solution interface: experimental approaches
Authors: Shchukarev A. 
Published: March 2006

AbstractXPS is a very useful technique to study physicochemical phenomena at the solid–solution interface. It is essential that the interface remains unaltered during sample preparation and analysis.Experimental approaches dealing with this problem are reviewed and discussed. They include differential pumping, controlled adsorption/condensation from gas phase, fast freezing, and freeze‐drying. A recently developed fast‐freezing procedure of wet pastes that are obtained from powder suspensions by centrifuging is described. This method allows for estimating surface point‐of‐zero charge, thickness, and potential of electrical double layer from XPS data. New experimental findings on mineral–solution interfaces are presented. Copyright © 2006 John Wiley & Sons, Ltd.
Corrosion behaviour of AlN and TiAlN coatings on iron
Authors: Marco J. F. , Agudelo A. C. , Gancedo J. R. , Auger M. A. , Sánchez O. , Albella J. M. 
Published: March 2006

AbstractWe have studied the corrosion behaviour of AlN and TiAlN coatings deposited by magnetron sputtering on pure iron substrates. The samples have been subjected to two different corrosion tests: (i) a Prohesion test and (ii) an accelerated corrosion test in constantly humid SO2‐polluted atmospheres. The transformations induced in the coatings by the aggressive environments have been followed by X‐ray photoelectron spectroscopy (XPS). The results indicate that under the corrosion conditions of the Prohesion test, the TiAlN coatings confer on the substrate a more efficient protection than the AlN coatings. Under the conditions of the accelerated corrosion tests in SO2‐polluted atmospheres, the behaviour of both coatings is very similar in the initial stages since in both cases the corrosion of the underlying iron occurs just after 1 day of exposure to the aggressive conditions. However, it seems that once the corrosion has started it progresses faster under the AlN coating than under the TiAlN coating. The XPS results also show that the TiAlN coating is more chemically inert than the AlN coating, which suffers chemical transformations under the influence of the two different aggressive conditions considered. The better performance of the TiAlN coating is attributed to its denser microstructure since these AlN coatings have been observed to grow in a more open columnar structure. Copyright © 2006 John Wiley & Sons, Ltd.
Characterization of polymer thin films deposited on aluminum films by the combined optical method and atomic force microscopy
Authors: Franta Daniel , Ohlídal Ivan , Klapetek Petr , Nepustilová Růžena , Bajer Svatopluk 
Published: March 2006

AbstractIn this paper, the results of the optical characterization of polymer thin films, deposited by the plasma enhanced chemical vapor deposition on the aluminum films performed by the multisample modification of the optical method based on combination of variable angle spectroscopic ellipsometry and near‐normal spectroscopic reflectometry, are presented. Within this characterization, the existence of roughness of the boundaries of the polymer films is taken into account by means of the Rayleigh–Rice theory. The optical constants of these films are described by the dispersion model based on parameterization of the density of electronic states. It is shown that the optical constants of the polymer films depend on their thicknesses, i.e. on the deposition times. Morphology of the upper boundaries of the polymer films is also studied using atomic force microscopy. Copyright © 2006 John Wiley & Sons, Ltd.
Theoretical determination of the surface excitation parameter from X‐ray photoelectron spectroscopy
Authors: Pauly N. , Tougaard S. , Yubero F. 
Published: March 2006

AbstractThe surface excitation parameter (SEP) is determined by analysis of X‐ray photoelectron spectroscopy (XPS) model developed by Simonsen, Yubero and Tougaard (Phys. Rev. B. 1997; 56: 1612). The model includes excitation due to the static core hole as well as the effect of the surface. The only input in the model is the dielectric function of the medium. More precisely, the SEP is extracted from the theoretical spectrum by calculating the ratio between the surface loss part of the spectrum and the elastic peak intensity. The angular distributions of the SEP are calculated for aluminium and silicon for photoelectrons of 1 and 3.4 keV energy. The SEP for XPS is found to be slightly (5–10%) smaller compared to that for reflection‐electron‐energy‐loss spectroscopy (REELS) calculated within the same model, and this difference is ascribed to the effect of the static core hole. Copyright © 2006 John Wiley & Sons, Ltd.
XPS study of supported gold catalysts: the role of Au0 and Au+δ species as active sites
Authors: Casaletto M. P. , Longo A. , Martorana A. , Prestianni A. , Venezia A. M. 
Published: March 2006

AbstractGold nanoparticles supported on different oxides (SiO2, CeO2 and TiO2) were prepared by the SMAD (solvated metal atom dispersion) and deposition–precipitation (DP) techniques. The physical and chemical characterization of the catalysts was performed by X‐ray photoelectron spectroscopy (XPS) and X‐ray diffraction (XRD) and the catalytic activity was tested during the reaction of low temperature CO oxidation. The structural and surface analyses evidenced the presence of small gold crystallites (cluster size ∼2–5 nm) in all the SMAD‐prepared samples and oxidized gold species in the case of the DP catalysts. A different surface distribution of ionic gold species was found on the different supports. By comparing the catalytic activities of the samples, the presence of Au+1 species seems to be the main requisite for the achievement of the highest CO conversion at the lowest temperature. The higher activity of Au/CeO2(DP) catalysts at T ≈ 250 K can be ascribed to a better stabilization of the AuO− species by the cerium oxide. Nanosized metallic gold particles exhibit a worse catalytic performance, both on ‘reducible’ and ‘inert’ supports, being significantly active only in the temperature range: 400–600 K. Copyright © 2006 John Wiley & Sons, Ltd.
Influence of phosphorus enrichment at grain boundaries on energy of intergranular fracture in Fe–Si–P alloys
Authors: Janovec J. , Pokluda J. , Jenko M. , Lejček P. , Vlach B. , Horníková J. 
Published: March 2006

AbstractAuger electron spectroscopy (AES) of in situ fractured samples was used to determine the grain boundary concentrations of phosphorus and silicon in polycrystalline Fe–Si–P alloys annealed at 800 °C for 100 h. These measurements were supplemented by mechanical testing and evaluation of fracture surfaces to obtain values of the energy of intergranular fracture. The effect of segregated phosphorus on the energy of intergranular fracture is discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Influence of the matrix on the chemical surface bonds of ZnS and CdS nanoclusters obtained by chemical synthesis
Authors: Mirenghi Luciana , Antolini Francesco , Tapfer Leander 
Published: March 2006

AbstractCadmium sulfide (CdS) and zinc sulfide (ZnS) nanocrystals were grown following three different chemical synthesis routes. In particular, the nanocrystals were synthesized byin situthermolysis (∼300 °C) starting from a metal thiolate (i) in a solventless way, (ii) by a novel route in trioctylphosphine oxide (TOPO), and (iii) by direct synthesis in a polystyrene matrix. The formation of cadmium sulfide (zinc sulfide) nanocrystals and the chemistry of the organic/nanocrystal (polymer/nanocrystal) composites were investigated in detail by X‐ray photoelectron spectroscopy (XPS). In addition, X‐ray diffraction analyses (XRD) were performed in order to determine the crystallographic structure and the average size of the nanocrystals.The precursor powders (Cd(SR)2and Zn(SR)2) of both II–VI compounds were analysed after annealing in different atmospheres (air, nitrogen, vacuum) at 300 °C (in situthermolysis) in order to establish the starting of the nanocrystal formation process.All the three chemical routes employed and investigated here, showed the formation of CdS (and ZnS) nanocrystals. X‐ray diffraction analyses evidenced that under optimized growth conditions single crystal nanoclusters of zinc‐blende structure and of diameter between${\oslash} = 1.5$and 3.0 nm (depending on the annealing temperature and time) are formed. Very good and promising results were obtained by the novel route in TOPO that revealed that sulfur has only one component on the S 2p unresolved doublet (at about 161.6 eV ±0.2) associated to the metal‐sulfide bond, i.e. the Cd(Zn)–S nanocrystals are capped by metal‐sulfide‐TOPO chains. CdS and ZnS nanocrystals embedded in a polystyrene matrix were also successfully prepared and the XPS analyses revealed, in particular, that the sulfur doublet signal is split at least into two peaks, compatible with S in CdS structure and with S bonded to organic residues with energies of 161.66 and 166.98 eV respectively. Copyright © 2006 John Wiley & Sons, Ltd.
Thin film a‐C/Pt nanocomposite catalysts for toxic gas sensors
Authors: Baranov A. , Fanchenko S. , Calliari L. , Speranza G. , Minati L. , Kharitonov S. , Fedoseenkov D. , Shorokhov A. , Nefedov A. 
Published: March 2006

AbstractWe compare the sensitivity of electrochemical gas sensors employing either traditional working electrodes based on platinum black or new working electrodes based on a‐C/Pt films deposited by magnetron sputtering (MS). The new electrodes are shown to be five times less sensitive as compared to the traditional ones. However, their Pt content is about 25 times less as compared to traditional electrodes, which suggests a more efficient use of Pt. Morphological, compositional and structural investigations are performed to understand the electrochemical behaviour of the two electrodes. Copyright © 2006 John Wiley & Sons, Ltd.