Search

A new method of X-ray photoelectron spectra processing based on a target model with a stochastic surface layer is proposed. On the basis of this model, X-ray photoelectron spectra of multilayer multicomponent metallic targets with an inhomogeneous surface layer are obtained for various probing angles considering surface shading effects. A layer-by-layer phase profile of metallic samples is obtained using the advanced method of surface analysis based on angle-resolved X-ray photoelectron spectroscopy. The results are validated by atomic force microscopy. [ABSTRACT FROM AUTHOR]

This study investigated the effects of oxygen (O2) flow rates and annealing temperatures on optical, electrical, and structural properties of indium–gallium–zinc oxide (IGZO) film on glass substrates fabricated by using a co-sputtering system with two radio-frequency (RF) (In2O3 and Ga2O3) and one direct current (DC) (Zn) magnetron. The average transmittance and optical energy gap increased significantly when the oxygen flow rate was increased from 1 sccm to 3 sccm. An increased O2 flow during co-sputtering IGZO films caused the crystallinity of the InGaZn7O10 phase to increase, yielding a smoother and more uniform granular structure. The carrier mobility rose and the carrier concentration decreased with increasing O2 flow. The results of X-ray photoelectron spectra (XPS) analyses explained the impacts of the O2 flow rates and annealing temperatures on optical and electrical properties of the co-sputtered IGZO films. The optimum process conditions of the co-sputtered In2O3-Ga2O3-Zn films were revealed as an O2 flow rate of 3 sccm and an annealing temperature at 300 °C, which showed the largest average transmittance of 82.48%, a larger optical bandgap of 3.21 eV, and a larger carrier mobility of 7.01 cm2 V−1s−1. XPS results at various annealing temperatures indicated that the co-sputtered IGZO films with an O2 flow rate of 3 sccm have more stable chemical compositions among different annealing temperatures. [ABSTRACT FROM AUTHOR]

We developed PEDOT:PSS [poly (styrenesulfonate)-doped poly(3,4-ethylenedioxythiophene] and tungsten oxide (WO3) based hybrid thin films by facile hydrothermal method. The solution processed WO3–PEDOT:PSS hybrid thin films are fully characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV–Vis (UV), Raman, X-ray photoelectron spectra (XPS) and Brunauer–Emmett–Teller (BET) surface area analysis. XRD and SEM results suggest that WO3 has crystalline structure with monoclinic phase and spherical shaped nanoparticles (20–25 nm), which is uniformly decorated on the surface of PEDOT:PSS sheets. The value of Eg [calculated by linear extrapolating of (F(R ∞) hν)2 and hν] was evaluated to be 3.11 and 2.85 eV for pure WO3 and WO3/PEDOT:PSS, respectively. The PL intensity of WO3/PEDOT:PSS is maximum lower than the pristine WO3 and PEDOT:PSS, implying an improved interfacial contact quality at the WO3/PEDOT:PSS. Photovoltaic performance of WO3–PEDOT:PSS devices were measured under AM 1.5 G 1 sun light intensity of 100 mW/cm2. Organic solar cell devices with WO3–PEDOT:PSS layer give rise to a significant increase in JSC from 9.35 ± 0.03 to 16.2 ± 0.01 mA/cm2 respectively and in VOC from 0.28 V to 0.72 V respectively, resulting in a remarkable PCE increase from 0.592 ± 0.03 to 0.714 ± 0.02%. The WO3/PEDOT:PSS composite deliver a PCE of 7.81 ± 0.01%. The superior performance of WO3/PEDOT:PSS composite was attributed to the reduced current leakage, enhanced hole extraction characteristics, and less trap-assisted interfacial recombination via current density–voltage. [ABSTRACT FROM AUTHOR]

In this work, an environmentally friendly and cost-effective one-step electrodeposition technique was used to synthesize Ag-doped CuSbS2 (CAS) thin films to optimize the photoelectrochemical (PEC) properties. An experimental study was performed on undoped and doped samples by tuning the concentrations of silver chloride (AgCl), as Ag doped precursor. The impact of Ag-coating on structural, physical properties, and PEC performances of electrodeposited CAS thin films have been thoroughly characterized using X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectra (XPS), scanning electron microscopy (SEM), ultraviolet–visible spectroscopy (UV–Vis) and electrochemical impedance spectroscopy (EIS). XPS measurements corroborated the incorporation of Ag ions into the host CAS photocathodes. Under optimized Ag-coating degree (10 at.%Cu) (ACAS10), the photocurrent density of the built photocathode generates a maximum photocurrent density up to ca. − 0.52 mA cm−2 at 0 V vs. RHE (reversible hydrogen electrode), which is approximately 10 times higher than the undoped one. In addition, a considerable anodically shift in the onset potential could reach 0.48 V vs. RHE. Internal photon-to-current conversion efficiencies (IPCEs) measurements showed the spectral distribution of the photocurrent generation revealing a broad response of the CAS-based photocathode. The stability tests were investigated for all the photoelectrodes at 0 V vs. RHE and revealed that the photocurrent retention could be obtained under chopped illumination for 10 min. The flat band potential (Vfb = 0.46 V vs. RHE) and acceptor coating density NA = 1.2 1018 cm−3 were estimated by Mott Schottky measurements. The Nyquist plot displays only one well-shaped semicircular arc, which approves the good homogeneity of all found CAS photocathodes. We believe that the optimized Ag-coating process of the CAS photocathode is an effective and efficient tuning of the physical properties resulting in boosted PEC properties for generating solar fuels from water. [ABSTRACT FROM AUTHOR]

PTCDI-C8 molecules are vapor-deposited onto reconstructed Si(100)—(2 × 1) surface under ultra-high vacuum. X-ray photoelectron spectra reveal a bond formation between oxygen atoms of the molecules' carboxylic groups and Si dangling bonds of the substrate. Following PTCDI—C8 film growth, ultraviolet photoelectron spectra show a drop in the HOMO level with respect to the Fermi level from 1.8 eV to 2.0 eV and a monotonic work function increase from 2.5 eV up to 3.3 eV. For a film thickness of 6.0 nm, a difference of 1.5 eV between the HOMO level of the film and the valence band maximum of the substrate is accomplished. [ABSTRACT FROM AUTHOR]

A novel p-n heterostructural film photocatalyst of oriented NiS/TiO2 nanosheets arrays was designed and successfully fabricated via a simple spin coating technique and its photodegradation activities of hydrogen (H2) evolution were investigated in detail. The physical and chemical properties of the as-obtained NiS/TiO2 nanosheets samples were investigated by a variety of analytical techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), Raman, UV–Vis spectra, photoluminescence (PL), N2 adsorption–desorption and X-ray photoelectron spectra (XPS). Combining p-type NiS with n-type TiO2 nanosheets to construct distributed p-n heterojunctions, the absorption edge of NiS/TiO2 red-shifted to about 481 nm and its photoresponse in visible range significantly enhanced and the optical band gap in reduced from 3.14 to 2.55 eV. The 10-NiS/TiO2 composite films showed higher surface area (112.3 m2/g) than compared with pristine NiS (66.5 m2/g) and TiO2 (77.1 m2/g). The optimum NiS loading content was found to be 10 wt% and the corresponding hydrogen production rate is ca.7481.1 μmolh−1 g−1, being about 17 times higher than that of pure TiO2 (450.4 μmolh−1 g−1). Correlation analysis suggests that the excellent H2 photocatalytic activity of the NiS/TiO2 p-n heterostructures would stem from the synergy effects between the high efficient charge separation and transfer driven by the built-in electric field at interfaces of NiS/TiO2. [ABSTRACT FROM AUTHOR]

The optical properties of 5wt% Fe3O4-TiO2 thin films were evaluated in detail with the aim of proposing a mechanism for solar photocatalytic processes and highlighting the advantages over the use of bare TiO2. The results showed that the incorporation of 5wt% Fe3O4 enhanced the optical properties by a redshift to a wavelength in the visible range, reducing the anatase/rutile band gap energy from 3.2 eV to 2.8 eV. Photoluminescence studies reveal a superior separation efficiency of photoexcited electron-hole pairs when Fe3O4 nanoparticles (NPs) are present in the photocatalyst. X-ray photoelectron spectroscopy spectra confirm the presence of Fe3O4 and existence of a chemical bonding between TiO2 and Fe3O4 NPs. Moreover, in this study, a mechanism of solar photocatalytic processes involving Fe3O4-TiO2 thin films is proposed and it is supported by experimental results. Finally, solar photocatalytic experiments were carried out, indicating that the effectiveness for the removal of the selected pharmaceutical is considerably improved when the composite material is used as catalyst. Furthermore, it was demonstrated that the photocatalytic activity of the prepared Fe3O4-TiO2 thin films depends on their thickness, achieving the highest pharmaceutical removal yields using the 2 µm thick sample. The stability and reusability of the catalyst was confirmed studying the photocatalytic activity over three cycles. [ABSTRACT FROM AUTHOR]

Antimony (Sb)‐doped tin oxide (ATO), as a transparent conducting oxide, is successfully deposited through atomic layer deposition (ALD). Thin films (≈270 nm) with various dopant concentrations are fabricated by sequential mixing of Sn‐ and Sb‐containing oxide layers in each ALD supercycle. The crystal structure, chemical composition, and morphologies of different films are characterized. Increasing the dopant concentration decreases the lattice parameter along the c‐axis and the overall grain size, as observed from X‐ray diffraction patterns and scanning electron microscopy images. X‐ray photoelectron spectroscopy spectra show increasing Sb content with increasing Sb to Sn subcycle ratio. The plasmonic loss feature, which is usually observed in highly doped degenerate semiconductors, is also found. Hall measurements are carried out to determine the electrical properties of each film, and films with ≈5% dopant concentration show the optimal conductivity. The carrier concentration continues to increase with increasing dopant concentration in the range of 0–20%, while the mobility decreases, which leads to a trade‐off and results in an increase in resistance if the dopant concentration exceeds 5%. The optimized ATO ALD process is demonstrated to fabricate core–shell structured nanotube arrays, which show its potential usage for photoelectrochemical applications. [ABSTRACT FROM AUTHOR]

We report the microstructure, optical and electrical properties of Al 1.5 Ga 0.5 O 3 thin films implanted by 180 keV Fe and Co ions. The X-ray diffraction pattern confirmed rhombohedral structure with R 3 ‾ c space group for pristine and Fe-implanted films. The Co-implanted films showed amorphous structure. SRIM simulations suggested oxygen vacancy in the films. The atomic force microscopy confirmed the formation of spherical-shaped particles (17–20 nm) in Co-implanted GaAlO_Si_550 films. The RMS roughness of the GaAlO_Si_550 films increased from 19 nm to 25 nm at higher Co-ion implantation fluences. X-ray photoelectron spectroscopy supported the formation of oxygen vacancy and non-stoichiometry at surface of the films. Electrical conductivity of the films enhanced up to 10−2- 10−3 S/m by metallic Fe- and Co ion implantation. Optical band gap was found at ∼3.85 eV for GaAlO_Al_550 and ∼4.04 eV for GaAlO_Si_550 pristine films. Optical band gap was stabilized in the range of 3.75–4.52 eV for Fe- and Co-implanted films, which can be useful for opto-electronic device applications in the UV and deep blue region. • Microstructure, optical and electrical properties of Fe and Co implanted Al 1.5 Ga 0.5 O 3 films. • SRIM simulations and XPS study for implantation-induced structural formation. • The electrical conductivity of the implanted films enhanced up to 10−2 S/m. • The optical band gap of the films was found in the range of 3.77–4.52 eV. • The films can be useful for a wide range of opto-electronic applications in UV to IR regime. [ABSTRACT FROM AUTHOR]

The hybrid thin film comprising ZnO and TiO2 nanoparticles deposited on single‐walled carbon nanotube (SWCNT) was prepared by sol–gel process on aluminum‐coated silicon wafer. The spin‐coated films were further processed by heat treatment followed by hydrothermal process. The synthesized materials were characterized by X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM), and photoluminescence spectroscopy for band‐gap determination. The coated ZnO formed the nanodisk morphology on the surface of carbon nanotubes with TiO2 nanoparticles incorporated on Al/Si wafer. The FE‐SEM analysis before and after hydrothermal treatment with ZnO–TiO2–SWCNT/Al/Si was conducted. The surface properties of the prepared thin films were analyzed for Zn2p, Ti2p, C1s, and O1s of individual spectra by X‐ray photoelectron spectroscopy (XPS) analysis. Good reproducibility and quick response time were obtained for ultraviolet (UV) light‐sensing activity with ZnO/SWCNT and ZnO–TiO2/SWCNT nanocomposites exhibiting good hydrogen gas sensing activity. [ABSTRACT FROM AUTHOR]

The structural evolution of GaxGeyTe100-x-y glasses in the vicinity of GeTe4-GaTe3 pseudo-binary tie-line is determined with high-resolution X-ray photoelectron (XPS) and extended X-ray absorption fine structure (EXAFS) spectroscopies. The analysis of XPS data is complicated by similar electronegativity values for the constituent chemical elements, but then the interpretation is facilitated by information from complementary EXAFS analysis of the structure around each element independently. The results show 4/4/2 coordination for Ga/Ge/Te atoms and absence of Ga(Ge)-Ge(Ga) bonds or extended Te clusters in significant concentrations within the whole range of studied composition. The observed structural features correlate well with the measured basic physical properties of Ga-containing germanium telluride glasses. [ABSTRACT FROM AUTHOR]

This paper discusses the formation of the TiO x -SiO x nano-composite phase during annealing of ultrathin titanium oxide films (~27 nm). The amorphous titanium oxide films are deposited on silicon substrates by sputtering. These films are important for high-k dielectrics and sensing applications. Annealing of these films at 750 °C in the O 2 environment (for 15–60 min) resulted in the polycrystalline rutile phase. The films exhibit Raman peaks at 150 cm−1 (B 1g), 435 cm−1 (E g), and 615 cm−1 (A 1g) confirming the rutile phase. The signature TO (1078 cm−1) and LO (1259 cm−1) infrared active vibrational modes of Si– O –Si bond confirms the presence of silicon-oxide. The X-ray photoelectron spectra of the TiO x films show multiple peaks corresponding to Ti metal (453.8 eV); Ti4+ state (458.3 eV (Ti 2p 3/2) and 464 eV (Ti 2p 1/2)); and Ti3+ state (456.4 eV (Ti 2p 3/2) and 460.8 eV (Ti 2p 1/2)). The O1s XPS spectra peaks at 530–533 eV can be attributed to Ti–O and Si–O bonds of the TiO x -SiO x nano-composite phase in the annealed films. The depth profiling XPS study shows that the top surface of the annealed film is mainly TiO x and the amount of SiO x increases with the depth. [ABSTRACT FROM AUTHOR]

Amorphous and crystalline Zn 1 − x CoxS (x = 0. 1 , 0.3, 0.5) thin films were grown on sapphire (Al2O3) substrates by pulsed laser deposition at substrate temperature of 25∘C and 800∘C, respectively. The X-ray diffraction results show that the crystalline film has a cubic zinc blende structure and the crystalline quality decreased with increasing Co-doping concentration. The X-ray diffraction and X-ray photoelectron spectroscopy spectra reveal that the samples reached an overdoping state at Co-doping concentration of x = 0. 5. The absorbance of films increases and the absorption edge shifts to longer wave length direction with increasing Co-doping concentration. The redshift of the band gap energy depends on the Co composition associating with the Urbach energy. Furthermore, the refractive index and dielectric constant increase with increasing Co-doping concentration. The dispersion parameters, such as dispersion energy ( E d ), oscillator energy ( E o ), static refractive index ( n 0 ), static dielectric constant ( ϵ 0 ), interband transition strength moments ( M − 1 and M − 3 ), oscillator strength S o and oscillator wavelength λ o , have been analyzed by Wemple–DiDomenico single oscillator model. All these parameters were found to be dependent upon the Co-doping concentration in the Zn 1 − x CoxS thin films. [ABSTRACT FROM AUTHOR]

• Amorphous MoO 3 thin films were deposited by rf sputtering using a Mo target. • Films were grown under different values of working pressure and sputtering power. • The presence of Mo6+, Mo5+, and Mo4+ oxidation states indicates formation of several compounds. • The photocatalytic activity was evaluated by the degradation of methylene blue. • The highest photocatalytic activity corresponded to films grown at 8.0 mTorr and 40 W. The photocatalytic activity of molybdenum trioxide (MoO 3) thin films was studied. The MoO 3 thin films were deposited on Corning glass substrates by radio frequency reactive magnetron sputtering using a metallic Mo target. The dependence of the physical properties of the metal oxides on the sputtering power and working pressure was investigated. X-ray diffraction patterns of the films revealed the formation of amorphous structures. From optical absorption spectra, the band-gap energy was obtained in the range 2.8–3.0 eV for most compounds, while this parameter decreased down to 1.64 eV for samples deposited at 4.5 mTorr and 80 W. X-ray photoelectron spectra disclosed signals associated with the Mo6+, Mo5+, and Mo4+ oxidation states, which correspond to MoO 3 and other substoichiometric molybdenum oxides. The photodegradation of a methylene blue (MB) aqueous solution was chosen to evaluate the photocatalytic performance of the thin films. There was found a dependence of the photocatalytic activity on the working pressure, with the samples deposited at 8.0 mTorr and 40 W displaying the highest MB removal. [ABSTRACT FROM AUTHOR]

Pure and Dy doped WO 3 thin films have been prepared by the physical vapor deposition method of electron beam evaporation technique under a pressure of 1 × 10−5 mbar. Films start out amorphous and become crystalline when they are annealed at 350 °C. The diffraction peaks of the X-ray diffractogram are associated with mixed triclinic and monoclinic phases which is determined by performing Rietveld analysis and confirmed by Raman spectroscopy. X-ray photoelectron spectra of the prepared WO 3 thin films confirm the presence of six valent tungsten (W+6) and trivalent Dysprosium (Dy+3) in the samples. The even and homogeneous distribution of the particles is visible in SEM pictures of the prepared WO 3 thin films. The energy band gap values show a significant decrease on annealing and fall more with Dy doping as a result of the emergence of intermediate states. The annealed films have superior transmittance compared to the non-annealed films which are in amorphous state The prepared thin films' PL emission spectra at 410 nm excitation wavelength exhibit blue, green, and yellowish green emissions as a result of optical band-to-band transitions of oxygen vacancies. Due to the existence of defects like oxygen vacancies, strain, etc., amorphous system, or non-annealed films, have shown better photoluminescence at higher rare earth ion concentration than crystalline system, or annealed films. After annealing the thin films, the overall colour hue of the emitted light can be shown to change from cold white to warm white using the Commission International de l'Eclairage (CIE) diagram. These findings imply that numerous lighting applications can make use of the prepared thin films. According to magnetic experiments, Ferromagnetism (FM) increases with Dy doping due to disparity in oxygen vacancies which is consistent with the results of the Pl experiment. The BMP model was used to discuss these results. The magnetic parameters derived from the fitted data are in good accord with the literature, and the experimental results suit the BMP model well. • Pure and Dy doped WO 3 thin films are prepared by e− beam evaporation technique under a pressure of 1 × 10−5 mbar. • All the prepared thin films show mixed triclinic and monoclinic phases. Decrease in band gap is observed with Ti doping. • X-ray photoelectron spectra confirm the presence of six valent tungsten and trivalent Dysprosium in the samples. • According to magnetic experiments, Ferromagnetism (FM) increases with Dy doping due to disparity in oxygen vacancies. • Due to existence of oxygen vacancies, amorphous system have shown better photoluminescence than crystalline system. [ABSTRACT FROM AUTHOR]

Thin Sn films on Ag(111) grown at different Sn coverage and substrate temperature were characterized with low-energy electron diffraction and x-ray photoelectron spectra. The results show that surface alloying of Sn atoms on Ag(111) occurs at a temperature as low as 96 K, indicating a strong tendency to form a surface alloy between Sn and Ag. During the alloying, Sn atoms substitute Ag atoms in random locations, resulting in a disordered Sn/Ag(111) surface. The alloy surface becomes completely ordered with a (√3 × √3) R30° reconstruction (the √3 phase) only when it is annealed above 453 K, but annealing at 403 K converts all Sn atoms on Ag(111) into the alloy state; the surface coverage of Sn is no more than 1/3 monolayer with excess Sn diffusing into the Ag(111) substrate. These observations indicate that the √3 phase with the Sn-Ag surface alloy is the only ordered phase obtainable on Sn/Ag(111) once the Sn-Ag surface alloy is formed. It is consequently impracticable to grow non-alloy ordered phases, such as stanene, on Ag(111) epitaxially at a temperature above 96 K, showing evident discrepancies with the conclusions of the previous computational study. • Sn/Ag(111) thin films grown at different conditions are studied. • Sn-Ag alloying on Ag(111) occurs at a temperature as low as 96 K. • Annealing above 403 K converts all Sn atoms into alloy states. • Sn/Ag(111) has a completely ordered √3 phase only when annealed above 453 K. • Non-alloy ordered phases do not exist on Ag(111) when Sn is deposited above 96 K. [ABSTRACT FROM AUTHOR]

In this paper, x mol% Mn-doped SrTiO 3 (STM x , x = 0, 0.5, 1, 3 and 5) thin films were synthesized by a sol-gel method. The effect of Mn doping on the microstructure and electrical performance was investigated. STM x (x ≤ 1) thin films shows a single cubic perovskite phase while impurity phase appears for STM3 and STM5 thin films confirmed by X-ray diffraction. X-ray photoelectron spectra reveals that STM1 thin film has the lowest concentration of oxygen vacancy. The dielectric constant and loss of STM x (x ≤ 1) films display good frequency stability, while decrease with the frequency for STM3 and STM5 thin films. And all samples display excellent bias stability of dielectric constant; this is advantageous for applications in a high electric field. The ferroelectric test demonstrates that the electrical breakdown strength increases and leakage current decreases for Mn doped SrTiO 3 films. A great recoverable energy storage density of 23.8 J/cm3 with an efficiency of 69.8% at 2.286 MV/cm is obtained in STM1 thin film. Furthermore, STM1 thin film shows good frequency stability of energy storage properties. It indicates that Mn doping is a simple and effective method to improve the energy storage properties of dielectric capacitors. [ABSTRACT FROM AUTHOR]

The diversity of carbon materials has allowed them to be used for fundamental and applied research to date. The newest modifications of carbon, such as nanodiamonds, graphene, fullerenes, and nanotubes, are of particular interest owing to their outstanding physical and chemical properties, as well as to prospects of their practical application in various fields of industry, from medicine to nanoelectronics. At the same time, one-dimensional forms of carbon, predicted in the 1960s, were underestimated because of imperfection of experimental tools [1-3]. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A family of systematically elongated tetraphosphonate corrosion inhibitors is studied by XPS. • The tetraphosphonates stringly interact with the mild steel surfaces at pH 3. • Shorter chain lengths on the inhibitor backbone cause surface dissolution. Abstract We study the interaction of six systematically varied tetraphosphonate molecules with carbon steel surfaces by XPS at pH 3. All tetraphosphonates [EDTMP (C2), TDTMP (C4), HDTMP (C6), ODTMP (C8) and DDTMP (C12)] belong to the aminomethylene-phosphonate family, and they possess systematically elongated backbone (from two to twelve methylene groups separating the N atoms). XPS studies were performed on powdered samples and also on immersed carbon steel specimens in aqueous solutions. The XPS results also suggest that the tetraphosphonic acid molecules become significantly deprotonated upon interaction with the carbon steel surface and that the surface interaction of the tetraphosphonic acid family leads to additive adsorption on the steel surface via the phosphonate groups. The mode of corrosion inhibition was studied by potentiodynamic polarization and electrochemical impedance spectroscopy. The changes observed in the impedance parameters, like charge transfer resistance (R ct) and constant phase element (CPE) confirm the strong adsorption on the metal surface. The nature of the protective layer formed on the carbon steel surface was examined by Attenuated Total Reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy and optical microscopy. [ABSTRACT FROM AUTHOR]

Characterization of samarium thin films molecular plated from N,N-dimethylformamide solutions onto stainless steel substrates, with either mirrorlike or brushed finishes, was carried out using a Thermo Scientific K-Alpha x-ray photoelectron spectrometer. Survey scans of the two specimens showed the presence of samarium, carbon, and oxygen with minor amounts of sodium. High-resolution spectra were then taken of the Sm 3d, O 1s, and C 1s regions. The chemical compositions of the two samples were found to be very similar, with the key difference being the relative amounts of two carbon species. Spectra from the survey and narrow high-resolution scans of the Sm 3d, O 1s, and C 1s regions are reported herein. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the relationship between the micro structure and the surface charge effect resulted during XPS surface analysis of amorphous carbon nitride thin films prepared by laser ablation method. The study results show that the charge effect coefficient ( E ) is not just a correction factor. We found that the changes in this coefficient value due to incorporation of nitrogen atoms into the carbon network are related to the spatial configurations of the sp 2 bonded carbon atoms, order degree and sp 2 clusters size. In addition, results show that the curve E vs. C(sp 3 )-N is a characteristic curve of the micro structure. This means that using this curve makes it easy to sorting the samples according to the micro structure (hexagonal rings or chains). [ABSTRACT FROM AUTHOR]

The preparation and electrical properties of N-doped ZnSnO (ZTO: N) thin film transistor (TFT) with a staggered bottom-gate structure were studied in this paper. ZTO: N thin film, which served as the active layer of the prepared TFT, was deposited on SiO 2 /p-type Si substrates by radio frequency magnetron sputtering at room temperature. Secondary ion mass spectroscopy (SIMS) analysis results showed all the species (Zn, O, Sn and N) were uniformly distributed in the thin film. X-ray Diffraction (XRD) patterns and scanning electron micrograph (SEM) images indicated that the thin film transformed from amorphous to crystalline states due to annealing. X-ray photoelectron spectra (XPS) proved that the oxygen-related defects in the thin film decreased after annealing. The thin film before and after annealing both showed a good optical transmittance of over 80% in visible light region. The TFT prepared with the thin film exhibited n-channel enhancement mode behavior and showed good electrical properties with a saturation mobility of 41.8 cm 2 V −1 s −1 , a threshold voltage of 5.4 V, and an on/off current ratio of 6.5 × 10 7 . [ABSTRACT FROM AUTHOR]

A (111) air-exposed surface of UO 2 thin film (150 nm) on (111) YSZ (yttria-stabilized zirconia) before and after the Ar + etching and subsequent in situ annealing in the spectrometer analytic chamber was studied by XPS technique. The U 5f, U 4f and O 1s electron peak intensities were employed for determining the oxygen coefficient k O = 2 + x of a UO 2+ x oxide on the surface. It was found that initial surface (several nm) had k O = 2.20. A 20 s Ar + etching led to formation of oxide UO 2.12 , whose composition does not depend significantly on the etching time (up to 180 s). Ar + etching and subsequent annealing at temperatures 100–380 °C in vacuum was established to result in formation of stable well-organized structure UO 2.12 reflected in the U 4f XPS spectra as high intensity (∼28% of the basic peak) shake-up satellites 6.9 eV away from the basic peaks, and virtually did not change the oxygen coefficient of the sample surface. This agrees with the suggestion that a stable (self-assembling) phase with the oxygen coefficient k O ≈ 2.12 forms on the UO 2 surface. [ABSTRACT FROM AUTHOR]

Molybdenum oxide (MoO x, x < 3) thin films were deposited on glass and (100) silicon substrates by thermal evaporation technique. Post-annealing of the samples was performed in O 2 by rapid thermal process at 373–673 K. The surface chemical, structural，morphological and optical properties of the samples were investigated. X-ray photoelectron spectra characterization verified the growth of sub-stoichiometric MoO x films as the coexistence of oxidation states of Mo 6+ and Mo 5+ . The O/Mo ratio of MoO x films increases from 2.58 to 2.75 when the annealing temperature increases to 473 K, but this ratio rapidly decreases at higher temperatures. The work function of MoO x films is proportional to O/Mo ratio and within the range of 5.40–5.95 eV. This correlation can be ascribed to the variation of Fermi level and surface dipole with oxygen vacancy. The MoO x films are polycrystalline with nanoparticles, and both α- and β-phase MoO 3 are co-existed with the annealing temperature from 373 K to 673 K . The optical band gap of MoO x films is in the scope of 2.72–2.95 eV. The three critical properties of MoO x films, such as work function, optical band gap and transmittance, are well-correlated to the variation of chemical configuration with the annealing temperature. [ABSTRACT FROM AUTHOR]

In the present contribution, bare and composite Mn3O4 (Mn3O4-X, with X = Ag, Au, or TiO2) thin films were fabricated by a two-step vapor-phase route, consisting in: (1) chemical vapor deposition of Mn3O4 on Si(100) substrates starting from a fluorinated β-diketonate diamine Mn(II) complex; (2) introduction of silver, gold, or titania by means of radio frequency (RF)-sputtering. The obtained results evidenced the formation of phase-pure α-Mn3O4 thin films chemically modified with fluorine, which after RF-sputtering yielded Mn3O4-X nanocomposite systems with tailored properties. In this work, data obtained by x-ray photoelectron spectroscopy characterization of the surface chemical composition are presented and discussed for bare and functionalized Mn3O4 systems. In addition to wide scan spectra, particular attention is dedicated to the analysis of C 1s, O 1s, Mn 2p, Mn 3s, F 1s and, eventually, Ag 3d, Au 4d5/2, and Ti 2p core levels, as well as silver Auger signal. In the case of the Mn3O4-Au system, a quantification procedure aimed at circumventing problems arising from the overlap of Mn 2p/Au 4p1/2 and Mn 3s/Au 4f signals is proposed. [ABSTRACT FROM AUTHOR]

The nanocrystalline V 2 O 5 thin films with different thicknesses have been grown onto the glass substrates using chemical spray pyrolysis (CSP) deposition method. The XRD study shows that the films exhibit an orthorhombic crystal structure. The narrow scan X-ray photoelectron spectrum of V-2p core level doublet gives the binding energy difference of 7.3 eV, indicating that the V 5+ oxidation state of vanadium. The FE-SEM micrographs show the formation of nanorods-like morphology. The AFM micrographs show the high surface area to volume ratio of nanocrystalline V 2 O 5 thin films. The optical study gives the band gap energy values of 2.41 eV, 2.44 eV, 2.47 eV and 2.38 eV for V 2 O 5 thin films deposited with the thicknesses of 423 nm, 559 nm, 694 nm and 730 nm, respectively. The V 2 O 5 film of thickness 559 nm shows the NO 2 gas response of 41% for 100 ppm concentration at operating temperature of 200 °C with response and recovery times of 20 s and 150 s, respectively. Further, it shows the rapid response and reproducibility towards 10 ppm NO 2 gas concentration at 200 °C. Finally, NO 2 gas sensing mechanism based on chemisorption process is discussed. [ABSTRACT FROM AUTHOR]

We report the optical and transport properties of transparent conducting Ta doped SrSnO 3 (SSTO) epitaxial films grown on MgO substrate by pulsed laser deposition. The effects of Ta ions doping on the microstructure and physical properties of SSTO films were investigated. Atomic force microscopy images confirm the smooth surface and low roughness of all films. X-ray photoelectron spectrum measurement shows that Ta ions are presented in the +5 state. All films have the optical transmittance of more than 90% in a wide wavelength range from 400 nm to at least 2000 nm. The band gaps of SSTO films calculated from the optical transmittances increase gradually from 4.45 to 4.63 eV with increasing Ta content. The SSTO films at x = 0.05 exhibit the lowest room-temperature resistivity of 3.33 mΩcm, and correspondingly the mobility reaches value as high as 18.5 cm 2 /Vs at a carrier concentration of about 1.01 × 10 20 cm −3 . This mobility value is much larger than that of our previously prepared Sb doped SrSnO 3 films. The metal-insulator transition of resistivity was analyzed using the Coulomb interactions and electron-electron scattering effects. Such a transparent conductive oxide with the perovskite structure has a promising potential application in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Er-doped TiO 2 thin films have been prepared by dual-frequency magnetron co-sputtering with two targets composed of TiO 2 and Er 2 O 3 . The structural and optical properties of these thin films were investigated using various characterization techniques. X-ray photoelectron spectroscopy measurements show that the content of Er increases when the power on Er 2 O 3 target increases. X-ray diffraction patterns indicate that the anatase TiO 2 peaks become weaker with the increasing power on Er 2 O 3 target and the films tend to form amorphous structure. Scanning electron microscopy results show that the grain size decreases with the rise in Er content. UV–vis spectrophotometric analyses reveal that the values of band gap decrease from 3.35 ± 1.3% eV to 3.02 ± 1.3% eV with the increasing amount of Er from 0 at.% to 3.2 at.%. The red shift in the optical adsorption edge may contribute to a higher photocatalytic activity of TiO 2 thin films. [ABSTRACT FROM AUTHOR]

• Sputtering conditions of thin films determine which of U-hydrides (UH 2 , α-UH 3 , β-UH 3) form. • X-ray photoelectron spectra and magnetic and transport properties obtained for all phases. • All U-hydrides are ferromagnetic. • Ferromagnetism is very robust and does not depend on structure details. Formation of thin uranium hydrides films, UH 2 and UH 3 , synthesized by direct current reactive sputtering of a uranium metal in an Ar-H 2 atmosphere, was explored using variable deposition conditions. Obtained U-H films were studied by a variety of methods, both in situ (photoelectron spectroscopy) and ex situ (x-ray diffraction, transmission electron microscopy, electrical resistivity, and magnetometry). Preparation of thin films allowed us to stabilize the non-existent in bulk UH 2 phase as well as the transient α-UH 3 (as a residual phase in UH 2) and the common stable β-UH 3 phase. All types of hydrides are ferromagnetic, the Curie temperatures of UH 2 and UH 3 (both α and β) are approx. 120 and 170 K, respectively. Ferromagnetism in the thin films is robust and does not depend on structure details while electrical resistivity data reflect disorder in both types of hydrides. [ABSTRACT FROM AUTHOR]

[Display omitted] • The NiO/β-Ga 2 O 3 HJDs with different β-Ga 2 O 3 orientations have been fabricated and characterized. • The substrate orientation dependent band alignment of the HJDs were identified by the transmittance spectra and XPS measurements. • The substrate orientation dependent electrical properties of the HJDs agreed well with the band structure determined by XPS. Due to the difficulty of p-type doping in β-Ga 2 O 3 , NiO/β-Ga 2 O 3 heterojunction becomes a promising candidate for fabricating bipolar devices. In this work, we performed a comparative study on the band alignment and electrical properties of the NiO/β-Ga 2 O 3 heterojunctions with different β-Ga 2 O 3 orientations. NiO thin films were sputtered on three β-Ga 2 O 3 substrates with (−2 0 1), (0 0 1) and (0 1 0) orientations and were subsequently fabricated into NiO/β-Ga 2 O 3 heterojunction diodes. A type-Ⅱ band alignment between the NiO and β-Ga 2 O 3 was identified by the transmittance spectra and X-ray photoelectron spectroscopy (XPS) measurements. The valence band offsets (VBOs) of the NiO/β-Ga 2 O 3 heterojunctions on (−2 0 1), (0 0 1) and (0 1 0) substrates were determined to be (2.12 ± 0.06) eV, (2.44 ± 0.07) eV and (2.66 ± 0.07) eV, respectively, and their corresponding conduction band offsets (CBOs) were (1.22 ± 0.06) eV, (1.49 ± 0.07) eV and (1.86 ± 0.07) eV. In addition, the fabricated heterojunction diodes showed good rectification properties with different turn-on voltages, which was in good agreement with the XPS results. The revealed influence of substrate orientations on the properties in NiO/β-Ga 2 O 3 heterojunctions were of great importance for the design and optimization of β-Ga 2 O 3 -based heterojunction devices. [ABSTRACT FROM AUTHOR]

The ZnO thin films of different (51.72 nm, 73.93 nm, 108.20 nm) thickness have been grown on glass substrate through atomic layer deposition (ALD). The effect of thickness on the morphology, optical and chemical state shift was investigated by X-ray diffractometer (XRD), UV–vis spectrometer, X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FESEM). The transmittance found to decrease with the increase in the ZnO thin film thickness. The morphological parameter such as grain size, strain, dislocation density and texture coefficient were calculated. The XPS chemical state analysis of O1 s peak of the ZnO thin film at different thickness revealed that dissociation of oxygen vacancies increased with the films thickness. The XPS high resolution spectra of Zn 2p 3/2 indicate the increase in the Zn concentration associated with the films thickness. The XRD data confirm the improved crystallinty with films thickness. The FESEM images also validate the results of XPS and XRD at different thickness. The XPS investigation reveals that the chemical state shift in the binding energy of the surface elements is associated with thickness of the deposited ZnO thin films. [ABSTRACT FROM AUTHOR]

Survey and high-energy-resolution spectra are reported for MBE grown GaAs (001) that had been capped with As. The As cap was removed by heating in situ prior to analysis. The current data expands upon the spectral regions previously reported in Surface Science Spectra. High energy resolution spectral features reported include: 2p, 3s, 3p, 3d, and L3M4,5M4,5 peaks for As; 2p, 3s, 3p, 3d, and L3M4,5M4,5 peaks for Ga; and the valence band region. [ABSTRACT FROM AUTHOR]

Ultra-thin WO 3 /TiO 2 bilayer thin films with various amounts of WO 3 materials were deposited on glass substrates using RF reactive magnetron sputtering in an attempt to enhance the photocatalytic activity and/or photoinduced hydrophilic conversion of titania-based materials. AFM images reveal changes in surface morphology on increasing WO 3 film thickness. Core level and valence band XPS spectra suggest band gap narrowing with the increase of tungsten atomic concentration in the bilayer structure. Both hydrophilic conversion and the photocatalytic activity of the surface were quantified via contact angle measurements. The latter process involved monitoring the contact angle changes induced by the decomposition of an additional oleic acid overlayer, as an effect of UV light irradiation. All the investigated samples exhibit similar photocatalytic features and close values for the hydrophilic conversion rates. [ABSTRACT FROM AUTHOR]

Traditional Korean lacquer films, such as Otchil and Hwangchil, are natural paints extracted from Rhus vernicifera and Dendropanax morbifera trees that grow in the eastern part and on the west and south coast of the Korean Peninsula, respectively. Rhus lacquer has a black color, and Hwangchil has a transparent gold color and a rich camphoric perfume (benzoin). These lacquers have been used since ancient times. In this study, analytical techniques, such as Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (TOF-SIMS),were used to study the traditional Rhus lacquer and Hwangchil films, avoiding time-consuming and destructive extraction procedures. To compare the Rhus and Hwangchil lacquers, reference lacquer films were prepared using Rhus and Dendropanax saps. These films were then analyzed using FT-IR, XPS, and TOF-SIMS. After establishing the methodology using the reference lacquer films, surface analytical techniques were applied to two different plates painted by an artist. The results suggest that FT-IR, XPS, and TOF-SIMS are simple and complementary analytical techniques for the discrimination of old lacquer films. [ABSTRACT FROM AUTHOR]

Fe (4 at.%) doped europium (III) oxide thin film was deposited on silicon (1 0 0) substrate by pulsed laser deposition technique. Structural, spectral and magnetic properties were studied by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and magnetization measurements. XRD and Raman spectroscopy reveal that the grown film is single phased and belongs to the cubic structure of Eu 2 O 3 . XPS study of the Eu 1.92 Fe 0.08 O 3 film shows that Fe exists in Fe 3+ ionic state in the film. The film exhibits magnetic ordering at room temperature. [ABSTRACT FROM AUTHOR]

Hybrid multilayer films based onthe two molecular species pararosaniline(PR) and Keggin-type polyoxometalate K5[PMo11VO40)] (PMo11V) were prepared on differentsubstrates using the electrostatic layer-by-layer (LbL) self-assemblymethod. The film buildup, monitored by electronic spectroscopy, showeda regular stepwise growth, and X-ray photoelectron spectroscopy dataconfirmed the presence of both molecular components within the LbLfilms. Scanning electron microscopy images revealed a completely coveredsurface with a nonuniform distribution of film components, and atomicforce microscopy images confirmed a rough surface. The film electrochemicalresponses and permeability were studied by cyclic voltammetry. Filmsrevealed three Mo-based redox processes (MoVI→MoV) and one V-based redox process (VV→VIV) in the potential range between 0.8 and -0.4 V vs Ag/AgCl.Studies with the redox probes [Fe(CN)6]3-/4-and [Ru(NH3)6]3+/2+showed thatthe films maintain the permeability even after six bilayers. Furthermore,the {PR/PMo11V}nmultilayerfilms exhibit excellent Mo-based electrocatalytic activity towardreduction of iodate and V-based electrocatalytic activity toward ascorbicacid oxidation, thus acting as a versatile multielectrocatalyst. [ABSTRACT FROM AUTHOR]

Rare earth is widely used in the fields of advanced materials, however, intrinsic reasons why rare earth should be added have been scarcely explained. Influences of europium on the structure and luminescent properties of CaWO 4 thin films have been investigated in detail. The problem whether sputtering yields are the same for compounds has also been studied in this paper. Results obtained from X-ray photoelectron spectra favor that Eu element embodies as Eu3+ and Eu2+ simultaneously. What is more, sputtering yields of Ca, W and Eu are 0.77, 0.77 and 0.80, respectively. Hence, it can be concluded that compositions of deposits agree well with those of targets. Studies on X-ray diffraction reveal that only when x chemical formula Ca 1–1.5x Eu x (VCa) 0.5x WO 4 is larger than 0.05, lattice constants will increase noticeably. Furthermore, the factor indicating preferential growth along the (004) plane of CaWO 4 crystals has increased from 0.3 to 47 when x has increased from 0.05 to 0.24. This phenomenon may be correlated with significant improvement made on crystal mismatch because of the substitution of Ca2+ with Eu2+. Photoluminescence examination clearly demonstrates that the optimal excitation corresponding to WO 4 2- has shifted from 223 to 200 nm due to doping of Eu. The excitation from 230 to 240 nm is ascribed to the charge transfer transition of O2-→Eu3+. Moreover, additional excitation band situated at 260–270 nm, which has been observed for Ca 0.64 Eu 0.24 (VCa) 0.12 WO 4 thin films, is regarded as the charge transfer transition of O2-→Eu2+. In addition, intense and sharp emission peaking at 615 nm has been observed for Ca 0.64 Eu 0.24 (VCa) 0.12 WO 4 thin film under ultraviolet light (200 nm ≤ λ ≤ 270 nm). [Display omitted] • Sputtering yields of Ca, W and Eu elements in Ca 0.64 WO 4 :Eu 0.24 compound are equal. • The preferential growth along the (004) plane has been greatly improved due to the existence of Eu2+ ions. • The optimal excitation corresponding to WO 4 2- ions has shifted from 223 to 200 nm due to doping of rare earth europium. • A novel charge transfer transition referring to O2-→Eu2+ has been proved. [ABSTRACT FROM AUTHOR]

In this work, copper indium gallium selenide (CIGS) thin films were prepared by sputtering CIGS quaternary target and subsequent annealing in the 450–550 °C range. For analyses purpose, the films were peeled off from Mo-coated glass and both parts were named as ‘CIGS side’ and ‘Mo side’ respectively. Raman spectroscopy and X-Ray Photoelectron Spectroscopy (XPS) were performed to identify crystalline phases and chemical compositions. On the ‘Mo side’, a MoSe x layer was evidenced with increased thickness for higher annealing temperature. On the ‘CIGS side’, XPS highlighted a continuous Ga enrichment and a Cu content decrease with increasing temperature. Na was detected on both Mo and CIGS sides. Its concentration and distribution relied on the temperature. Finally, relationships between interface modifications and annealing temperature were discussed . [ABSTRACT FROM AUTHOR]

Highlights: [•] Single phase CZTS thin films grown using a novel procedure. [•] Structural characterization through XRD and Raman measurements. [•] Determination of elemental composition through XPS analysis. [•] Stoichiometry of S:Sn:Zn:Cu=4.07:0.97:0.95:2.03 close to that of Cu2ZnSnS4. [Copyright &y& Elsevier]

Abstract: The electrophoretic deposition (EPD) technique is an attractive approach for development of graphene and graphene oxide (GO) films for a variety of applications. However, in order to establish the influence of the EPD parameters on the properties of the deposited films, a deeper investigation of the fundamental GO-EPD kinetics is required. Previous studies have reported a simultaneous anodic reduction of GO flakes during EPD, complicating the kinetics and process control. Therefore, in this study, low voltages were used to prevent significant GO reduction during EPD, as confirmed by XPS and FTIR. Accordingly, the GO-EPD kinetics was established as a function of deposition time and voltage, accompanied by microscopic characterization of the deposited films. The experimental results show that the deposition follows a linear growth law, in good agreement with the predictions of Hamaker’s law. Comparisons of optical absorbance and profilometry provide estimates of (reduced) GO deposition rate, extinction coefficient, and density. [Copyright &y& Elsevier]

Highlights: [•] Substrate–plasma polymer film interfaces were exposed allowing the underside of the films to be examined and compared with the top side. [•] Both sides of the plasma polymer films were examined using X-ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. [•] High input power during polymerization produced plasma polymer films with chemical gradients, which contain more ether units at the initial formation stage compared with the top layer. [•] Film chemistry was dependent on the type of substrate used for the plasma polymerization deposition. [Copyright &y& Elsevier]

Highlights: [•] Structural and electronic properties of SnO2 films were determined. [•] Oxidation states of the SnO2 thin films were confirmed by XPS analysis. [•] Chemical component is non-stoichiometric and ratio of oxygen to tin was 1.85. [ABSTRACT FROM AUTHOR]

Highlights: [•] Angle-resolved XPS method for thin-film studies. [•] Deconvolution of cation depth profiles within passive films from ARXPS data. [•] Comparison of passive films obtained in sulphuric and acetic acid. [•] Strong molybdenum enrichment on the oxide side of the oxide/metal interface. [•] Passive-film formation depends on metal oxidation potentials and ion solubilities. [ABSTRACT FROM AUTHOR]

Abstract: The use of high resolution X-ray photoelectron spectroscopy to study chalcogenide glass thin films is analyzed. It is shown that the method is an effective tool to explore different chemical environments in the films and control chemical composition of the surface. Examples of the method applications such as kinetics study of induced silver dissolution in the thin films and investigation of oxidation on the surface of the thin film are presented. Limitations of the method are shown on the example of photoinduced structural transformations in chalcogenide glass thin films. [Copyright &y& Elsevier]

Highlights: [•] LaAlO3 film was grown on GaAs by PEALD. [•] The LaAlO3 film remain amorphous after 500°C annealing. [•] The GaAs/LaAlO3 interface was optimized by in situ NH3 plasma nitridation. [•] In situ NH3 plasma nitridation improved electric properties of MOS. [ABSTRACT FROM AUTHOR]

Abstract: This work addresses the functionalization of chitosan thin films and its nanoliposomes blend films by a microwave-excited Ar/N2/H2 surface-wave plasma treatment which was found an effective tool to modify surface properties. Changes in the film properties (wettability, chemical composition, morphology) induced by the plasma treatment are studied using water contact angle measurements, X-ray photoelectron spectroscopy and scanning probe microscopy. The results suggest that hydrophilicity of the films is improved by plasma treatment in a plasma condition dependency manner. Water contact angle of chitosan films before and after plasma treatment are, respectively, 101° and 27°. Besides chemical changes on the surface, the nanoliposomes incorporation and plasma treatment also induce morphological modifications. Moreover, a correlation is found between the nanoliposomes composition and size, and the effects of plasma treatment. It is shown that the plasma treatment significantly improves the chitosan film functionalization. The effect of N2 content (88% and 100%) in the plasma gas mixture on the film etching is also pointed out. [Copyright &y& Elsevier]

Abstract: Potentiodynamic polarization studies were carried out on nanocrystalline I, nanocrystalline II and nanocrystalline III states having crystallite size 35±5nm, 18±2nm and 10±2nm of the alloy Ti60Ni40 in 1M H2SO4 aqueous medium. It was observed that the nanocrystalline III state exhibits superior corrosion resistance as compared to the nanocrystalline II and nanocrystalline I states of the alloy Ti60Ni40. XPS studies were also performed after corrosion test and it was observed that nanocrystalline III state contains only Ti2+ and Ti4+ species whereas nanocrystalline I and nanocrystalline II state contains Ti2+, Ti3+and Ti4+ along with some unoxidized metallic Ti0 in the case of nanocrystalline I state. Thus the small crystallite size and the presence of only Ti2+ and Ti4+ species in the form of TiO and TiO2 leads to the formation of a protective oxide film which is adherent, stable and improves the corrosion resistance of the nanocrystalline III state of the alloy Ti60Ni40. [Copyright &y& Elsevier]