This article presents an XPS study of Ce 3d emission spectra dominated by atomic multiplet effects in core level spectroscopy of rare earth compounds (Ce oxides). Core level spectroscopy has been used to study the electronic states of Ce 3d 5/2 and Ce 3d 3/2 levels in Ce 4+ and Ce 3+ states. The well-resolved components of Ce 3d 5/2 and Ce 3d 3/2 spin-orbit components, due to various final states (4f 0 , 4f 1 , 4f 2 configurations), were determined on 3d XPS spectra from commercial powders (CeO 2 , CePO 4 ).These results were used to study the 3d spin-orbit component of mixed cerium-titanium oxide. This compound was prepared by co-melting commercial powders of CeO 2 and TiO 2 at 1800 K under air using a solar furnace with a flux density of 16 MW.m −2 at the focal point of the parabolic concentrator. The mixed oxide Ce 2 Ti 2 O 7 was produced and contained Ce(III) species which may be reactive with water to give back the initial metal oxides and generate hydrogen, a valuable product considered as a promising energy carrier in the future in replacement of oil.The 3d photoemission spectra revealed the presence of mixed components attributed to mainly Ce(III) and Ce(IV) species.

This study addresses the synthesis, characterization, and thermochemical redox performance evaluation of perovskites and parent structures (Ruddlesden–Popper phases) as a class of oxygen-exchange materials for hydrogen generation via solar two-step water splitting. The investigated materials are La x Sr1–x MO3 (M = Mn, Co, Fe), Ba x Sr1–x (Co,Fe)O3, LaSrCoO4, and LaSrFeO4, also used as mixed ionic-electronic conductors in fuel cells. Temperature-programmed reduction, powder X-ray diffraction, and thermogravimetric analysis were used to obtain a preliminary assessment of these materials performances. Most of the perovskites studied here stand out by larger thermal reduction capabilities and oxygen vacancies formation at modest temperatures in the range 1000–1400 °C when compared with reference nonstoichiometric compounds such as spinel ferrites or fluorite-structured ceria-based materials. In addition, these materials offer noticeable access to metallic valence transitions during reoxidation in steam atmosphere that are not available in stoichiometric oxides. The promising behaviors characterized here are discussed in regard to the crystal chemistry of the perovskite and parent phases.

he capacity of hydroxyapatite (HA) for removal of lead from aqueous solution was investigated under different conditions, namely initial metal ion concentration and reaction time. The sorption of lead solution by synthetic hydroxyapatite was investigated with initial concentration in the solution containing Pb 2þ varying from 1000 to 8000 mg l À1. Pb and Ca analysis in the solutions, X-ray diffractometry associated with SEM-WDS and XPS analysis characterized the mechanisms of lead uptake. It was shown that the dissolution of hydroxyapatite is followed by the formation of hydroxypyromorphite, a solid solution of Pb 10Àx Ca x (PO 4) 6 (OH) 2 formula, with Pb ions mostly occupying Ca(II) sites, and that the Ca=P molar ratio of this solid solution decreases continuously. Classical adsorption isotherms were used to describe adsorption data. The adsorption capacity, k LF , of 320 mg Pb g À1 HA and the adsorption intensity, n LF , of 2.5 were calculated from Langmuir-Freundlich. This isotherm was at an initial pH 5 and 25 C for 16 mm mean particle size. This shows significant affinity of HA to Pb 2þ according to literature data.

) 1-x (CeO 2 ) 2x (ZrO 2 ) 2 mixed oxides (LCZ) where 0 ≤ x ≤ 1 were synthesised from commercial La 2 O 3 , CeO 2 and ZrO 2 powders and co-melted in a 2-kW solar furnace. These samples were re-oxidised in air at temperatures that ranged from 900 K to 1100 K. The microstructures of the LC, LCZ and CZ oxides were investigated by XPS and XRD. Core-level spectroscopy (XPS) has been used to study electronic states (III) and (IV) of the Ce 3 d 5/2 and Ce 3 d 3/2 levels. The resolved components of the Ce 3 d 3/2 , 5/2 features were identified. The rate of Ce 3+ and Ce 4+ states were calculated for different values of x (0.1-1). The nature of the chemical bonds of Ce and O were determined from the Ce 3 d 3/2,5/2 and O 1 s photoelectron peaks, respectively.The XRD study revealed the presence of solid solutions (LCZ and CZ). The presence of crystalline phases (pyrochlore and fluoritelike structures) depends on the value of x. A decrease in the lattice parameter was observed with increasing x. La atoms were substituted by Ce atoms in a solid solution, and the oxygen vacancies were filled. The amount of fluorite-like phase increases with an increasing amount of Ce atoms.

High Seebeck effects from conducting polymer: Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) based thin-film device with hybrid metal/polymer/metal architecture APL: Org. Electron. Photonics 5, 238 (2012) High Seebeck effects from conducting polymer: Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) based thin-film device with hybrid metal/polymer/metal architecture Appl. Phys. Lett. 101, 173304 (2012) Response to "Comment on 'Silver/silicon dioxide/silver sandwich films in the blue-to-red spectral regime with negative-real refractive index'" [Appl. Phys. Lett. 101, 156101 (2012)] Appl. Phys. Lett. 101, 156102 (2012) On the determination of the glass forming ability of AlxZr1−x alloys using molecular dynamics, Monte Carlo simulations, and classical thermodynamics J. Appl. Phys. 112, 073508 (2012) Enhanced photoanode properties of epitaxial Ti doped α-Fe2O3 (0001) thin films Appl.Chemical bonding and local order around the different atoms of thick amorphous SiC x N y deposits ͓0.03рx/(xϩy)р0.67͔ prepared with chemical vapor deposition at 1000-1200°C using TMS-NH 3 -H 2 have been investigated using x-ray photoelectron spectroscopy ͑XPS͒, Raman spectrometry, Fourier transform infrared spectrometry ͑FT-IR͒, electron energy loss spectroscopy ͑EELS͒ and 29 Si magic-angle spinning nuclear magnetic resonance spectrometry ͑MAS-NMR͒. XPS analyses have shown that the main bonds are Si-C, Si-N, and C-C, and have suggested the existence of C-N bonds. According to Raman analyses and complementary FT-IR absorption of thin films, the coatings are nonhydrogenated. Si, C and N atomic chemical environments are more complicated than in a mixture of pure Si 3 N 4 -SiC phases. The examination of the Si KL 2,3 L 2,3 line shapes recorded by XPS have allowed one to state the existence of Si(C 4Ϫn N n ) units. Mixed coordination shells around silicon have been confirmed by EELS analyses. Additionally, FT-IR reflection analyses have proved that Si is both bonded with N and C. Indirect indication has been obtained owing to the 29 Si MAS-NMR analyses of powders. Raman analyses have been conclusive to assume that C-C bonds correspond to a mixed sp 3 Ϫsp 2 carbon configuration linked with Si(C 4Ϫn N n ) tetrahedra with 0рnр4.

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