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The atomic environment of 20MnO · 80(xBi₂O_{3 · y}PbO) glass samples having the ratio of bismuth to lead atoms of 8:1 and 3:1 was investigated with respect to the thermal induced structural changes, cationic field strength and electronic structure of the compound. The position and full width at half maximum of X-ray photoelectron peaks were estimated using spectra simulation based on the summation of Lorentzian and Gaussian functions. Data obtained from XPS core-level spectra Bi 4f, Pb 4f, Mn 2p, and O 1s indicate a reduction of glass disorder both by heat treatment and by increasing the PbO content in the samples. The cations behave essentially as network formers that could be correlated with an intermediate range structure.

Experimental formation of LPO (liquid phase oxidation)-grown InGaP native oxide near room temperature (~60°C) is demonstrated. A high oxidation rate is obtained and checked by SEM and AES. The native oxide is determined to be composed of InPO₄ and Ga₂O₃, analyzed by the results of XPS measurement. Due to the presence of the excellent quality of InGaP native oxide, high hydrogen (H₂) sensitivity in output current of a Pd/oxide/InGaP MOS Schottky diode is observed. Under the applied voltage of -1 V and 50 ppm H₂/air, a high sensitivity of 1090 is obtained. An obvious variation of output current and a short response time due to the exposure to different H₂ concentration are also achieved. For example, the adsorption (τ_a) and desorption (τ_b) time constants under 50 ppm H₂/air are 2.3 s and 2.7 s, respectively.

In this paper, Nitinol, an equiatomic binary alloy of nickel and titanium, was surface modified for its potential biomedical applications by chemical and electrochemical etching. The main objective of the surface modification is to reduce the nickel content on the surface of Nitinol and simultaneously to a rough surface microstructure. As a result, better biocompatibility and better cell attachment would be achieved. The effect of the etching parameters was investigated, using scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectrometry (EDX) and X-ray photoelectron spectrometry (XPS). The corrosion property of modified Nitinol surfaces was investigated by electrochemical work station. After etching, the Ni content in the surface layer has been reduced and the oxidation of Ti has been enhanced.

In this paper, we report the effect of etching time on the morphological, structural and electrical properties of porous silicon (PSi) synthesized by electrochemical anodization of low resistivity p-type crystalline silicon at current density of 15 mA/cm². Atomic force microscopy (AFM) measurements showed that the square root of roughness is increased with etching time. Scanning electron microscopy (SEM) investigations revealed that the microstructure of porous silicon is varying with etching time and pores from nano-size to micro-size were formed. Energy dispersive X-ray (EDX) analysis confirmed that the amount of oxygen increases with etching time. Porosity and thickness estimated gravimetrically showed a dependence on the anodization time. The room temperature dark electrical resistivity of porous silicon has observed to be increased with etching time. X-ray photoelectron spectroscopy (XPS) analysis of synthesized porous silicon has shown peaks of C 1s, Si 2p, O 1s, F 1s and N 1s. Current–voltage (I–V) characteristics of synthesized Al/PSi/c-Si junctions prepared at different etching times are investigated and analyzed. The ideality factor, barrier height and built-in potential of porous silicon junctions were strongly found to be dependent on the etching time.

Ball milling technique has been extensively used to prepare different metastable states with nanocrystalline microstructures from intermetallic compounds. The present study was made on the identification of the changes in magnetic and electronic properties as a result of high-energy ball milling of Fe-50 at.%Al alloy samples. The phase formation and physical properties of the alloys were determined as a function of milling time by means of Mössbauer and X-ray photoelectron spectroscopy (XPS). The Mössbauer results show the formation of nanostructured body-centered cubic (BCC) FeAl alloy only after 5 h of mechanical milling and the same is also confirmed by Scanning electron microscope (SEM) and Transmission electron microscopy (TEM) studies. Mössbauer studies further confirm that there is magnetic behavior retention in the FeAl alloy samples even after 5 h of milling but magnetization decreases as the milling time increases. The reason for the same is due to the shocks and fracturing of the Al atoms embedded in the sites of Fe and as a result of which Fe–Fe nearest neighbors decreases. Secondly, with the increase in milling time, the particle size and the number density of equiatomic BCC Fe₅₀Al₅₀ grains decrease while the volume of grain boundary containing a solid solution of BCC FeAl and concentration of Al in a solid solution of BCC FeAl at the grain boundary increases as a result of which magnetization decreases. The shift in the binding energy of Fe_2p and Al_2p core level towards higher binding energy also supports the alloy formation after milling.

Titanium dioxide (TiO₂) film was deposited by the direct current pulse magnetron sputtering technique. Then the surface of TiO₂ film was implanted by the N ion beam at room temperature. Through this way, N-doped TiO₂ (N–TiO₂) film was obtained and the band gap of N–TiO₂ film was decreased to 2.97 eV. XPS result revealed that N ion was doped into TiO₂ film as Ti–N and Ti–NO bonds. N ion was substitutionally/interstitially doped into TiO₂ crystal lattice and Ti–N bond was formed. N ion was doped into amorphous TiO₂ and Ti–ON bond was formed. The polycrystal TiO₂ film could result in that more N ion was substitutionally/interstitially doped into TiO₂ crystal lattice, which could effectively narrow the band gap of N–TiO₂ film. This work provides a potential N doping method which could be applied commercially.

In this study, a leaf-like ${\mathrm{\text{Cu}}}_2\mathrm{\text{O}}/\mathrm{\text{CuO}}$ mixed phase nanosheets array was successfully prepared by anodization. XRD, EDS, and XPS analysis confirmed the formation of ${\mathrm{\text{Cu}}}_2\mathrm{\text{O}}/\mathrm{\text{CuO}}$ mixed phase nanostructures. SEM images indicate that the fabricated ${\mathrm{\text{Cu}}}_2\mathrm{\text{O}}/\mathrm{\text{CuO}}$ mixed phase nanosheets almost grow vertically on the substrate. The average height of nanosheets is approximately 500 nm. The optical absorption of the mixed phase covers the entire wavelength region of visible light and a little part of the near-infrared region of short wavelength.

An investigation was made on the electronic structure of 4d transition metal layered oxide material of Li₂RuO₃ using X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). The intensity of O $K$ pre-edge peak increased for Li ion extracted samples, suggesting increased ligand holes. The Ru 3d XPS spectrum suggested the variation of local structure around Ru ions by extraction of Li ions. We conclude that the delithiation from Li₂RuO₃ is charge compensated by O anions, and that the creation of the ligand holes reorganizes electronic structures composed of highly hybridized Ru 4d and O 2p orbitals.

The XPS 3d core level spectra of Ba in the oxygen annealed high T_c superconducting YBa₂Cu₃O_7−δ (δ~0.07) sample at 295 K and ~77 K show asymmetry. An attempt has been made to see the effects on the Ba 3d spectra due to air and nitrogen annealing as well as the substitution of magnetic Gd ions for Y ions. Our XPS results show that the observed asymmetry in the Ba 3d peaks is not associated with the superconducting behavior.

Experimental evidence for understanding the transport and electrical properties of the 10.4 K organic superconductor κ-(BEDT-TTF)₂Cu(NCS)₂ (where BEDT-TTF represents bis(ethylenedithio)tetrathiafulvalene) has been achieved by X-ray and ultraviolet photoelectron spectroscopic (XPS and UPS) measurements. Chemical environment of the atoms in this organic superconductor is discussed based on the XPS core-level results. Binding energies of the inequivalent C and S sites in the cation BEDT-TTF and the anion Cu(NCS)₂ are found to be different and an assignment is made. The valences of Cu and N were observed to be typically +1 and −3, respectively. The results indicate that bonding is somewhat covalent in the BEDT-TTF while it is ionic in the Cu(NCS)₂, i.e., conduction in this compound occurs essentially on the two-dimensional network of the BEDT-TTF molecules. Measurements of the valence band region revealed a broad valence band structure with several peak features.