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In photoemission, the Auger electron energy, combined with the respective photoelectron energy, provides the so-called Auger parameter α ′ which in the case of 3d transition metals, has been demonstrated to be influenced by the coordination state of the emitting atom. In the literature of electron spectroscopy for chemical analysis studies on titanosilicates, the Ti Auger parameter has typically not been reported. In this work, the X-ray photoelectron and the X-ray induced Auger electron spectra of a Ti silicalite (TS-1) and other crystalline mesoporous titanosilicates such as TiSBA-15 and TiMCM-41 have been measured. An α ′ value of 882.3 eV, ∼10 eV higher than in TiO 2 , has been found for part of the titanium in TS-1 and TiSBA-15 samples. Such a shift in the Auger parameter is attributed to tetrahedral coordination of Ti, substituting for Si atoms in the framework.

Synchrotron radiation X-ray photoemission spectroscopy has been used to study wear tracks produced during tribological tests on steel specimens. This was a successful feasibility test for the use of ultrabright synchrotron radiation in tribology. We found that the resulting high flux and small spot dimensions on a sample of 100×30 μm 2 , are ideal for testing disk samples having circular wear tracks with radius 1 cm and width 250 μm. A photon energy of 350 eV was used to analyse Zn 3d, P 2p, S 2p and C 1s peaks on samples produced in different conditions.

The application of SAM and XPS to the study of powder mixtures composed of silicon carbide and processing additives is presented. The density of sintered SiC specimens has been shown to be related to the surface composition of the freeze-dried mixtures, measured after milling the water slurries and after heating for the removal of binding polymers (dewaxing). Effects of milling and dewaxing on the dispersion of sintering aids, on the formation of residual carbon layers and on the evolution of the surface oxide have been tested by XPS while the spatial distribution of surface carbon species has been tested by SAM. The procedure for the acquisition of Auger spectra and linescans on these powder samples is described. SAM analysis of dewaxed SiC greens, reveals the presence of graphitic carbon agglomerates with an average diameter of roughly 5 μm after 1 h of mixing in attrilion mill which decreases to less than 1 μm after 16 h. The study shows that processing parameters such as type and concentration of sintering aid, milling time and dewaxing procedure can be optimized using the information of surface spectroscopies, acquired after each step of processing, for the production of high density specimens.

Ceramic powder mixtures composed of silicon carbide and processing additives such as boron, carbon and binding agents were investigated by X-ray photoelectron spectroscopy. The novelty of this work consists in the application of a surface analysis technique to the study of ceramic green bodies. The analysis of freeze-dried powders, obtained from aqueous suspensions of the mixtures, reveals a strong C1s lineshape dependence on the carbon dispersion and the milling procedure, which are important factors in the fabrication of high-density SiC components. In fact, the deconvolution of C1s bands allows a quantification of the spectral contribution of four carbon species assigned to C-Si, C-C, C-H and C-O species, so that a relative measure of the dispersion of carbon on the surface of the SiC particles is obtained. When carbon black or graphite are used as carbon additives it appears that carbon black is more dispersed than graphite at shorter milling times. For all samples studied, a good correlation is shown to exist between the intensity of the C-C carbon component in the C1s band and the density after sintering.

The alkali metal distribution in a variety of alkali doped ZnO catalysts has been studied and is shown to affect total methane conversion and C2 selectivity. When Na 2 CO 3 precursors are used, CO 3 2− groups decompose upon calcination and sodium penetrates into the ZnO matrix, even at high loading. In the case of lithium, layers of Li 2 CO 3 , proportional to the Li concentration, segregate on the ZnO and reduce the oxide active surface available for gas reaction. In the aim of determining the best preparation and reaction parameters a correlation between XPS evidences and catalytic data collected during the initial phase of reaction was attempted.

The new thermal analysis of thermovoltaic detection (TVD) is described and its application to various substances is presented. Basically, the technique consists of recording the EMF curve generated by the thermally decomposing sample in contact with two dissimilar metal electrodes (usually Al-Pt). The general shape of the curve, in reference to the temperature axis, enables it to be used for the qualitative identification of the substance. The curves are reproducible to within about ± 3–4% of each other. TVD curves of CuSO 4 · 5 H 2 O, [Co(NH 3 ) 6 ]Cl 3 , various polymers, organic acids, coal, tobacco, water, and ethanol are presented.

The thermal dissociation reactions of selected amino acids were studied by thermovoltaic detection (TVD), TG and DSC. All of the TVD curves except L-arginine contained a broad EMF output peak in the 200–300°C temperature range. The leading edges of the peak maxima were reproducible to within ± 1–2% while the trailing edges were reproducible to ± 20% or so. The latter was related to the irreproducible nature of the electrode-decomposition products interface. The TVD curves were not unique in that they yielded thermal analysis curves that were not inherently different from other TA techniques.

X-Ray photoelectron spectroscopic (XPS) studies of hydrated, dehydrated and, reduced Cu NaY zeolites were carried out. With sufficient analyzer resolution, both the Cu 2 p 1 2 and 2 p 3 2 transitions were resolved into two components in hydrated CuNaY. The higher-binding-energy component and the shake-up satellites decreased in intensity with dehydration. By correlation with electron spin resonance (ESR) and X-ray diffraction results the higher-binding-energy component is assigned to octahedrally coordinated Cu2+ in the large α-cages of the zeolite and the lower-binding-energy component to tetrahedrally coordinated Cu2+ in the small β-cages of the zeolite. On hydrogen reduction of dehydrated CuNaY the XPS transitions shift by 1 eV to lower binding energies which correlated with an order of magnitude decrease in the Cu2+ ESR intensity. These shifted transitions are assigned to Cu+ or possibly to Cu0.