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The excitation of bulk and surface plasmons in the presence of a solid surface during the emission of electrons in X-ray photoemission spectroscopy (XPS) and in Auger electron spectroscopy (AES) is investigated. The modifications in the energy loss spectra as well as in the plasmon excitations due to the sudden creation of electron–hole pairs, electron transport phenomena and the presence of residual holes and furthermore the proximity of the surface are analysed. The results illustrate that, from a theoretical point of view, separation of extrinsic and intrinsic contributions could be ambiguous (in terms of independent processes) due to interference effects between the photoelectron and photohole present in both processes. A comparison of the results of our model with experimental spectra showed a good agreement.

A series of X-ray photoelectron spectroscopic (XPS) measurements for testing the performance and determining the spectrometer function of electron spectrometers is described. The method is based on the determination of the natural line width Rh 3d 5/2 in Rh metal by the help of the Coster-Kronig broadening and Auger intensity ratio evaluated from the Rh 3d 3/2 and M45N45N45 Auger spectra, respectively. Applicability of the method is demonstrated in the case of different electron spectrometers, comparing the data obtained in this way to the results of an alternative procedure based on the analysis of conduction band photoelectron spectra of Rh metal samples.

X-ray photoelectron spectroscopy combined with argon ion etching was applied for the investigation of the structure of the oxide layers developed on stainless steel surfaces having been exposed to ion-free water of different temperatures. Photoelectron intensity ratios measured as a function of the ion etching time given information on the composition and depth structure of the oxide layer as well as of the uppermost layers of the alloy. Stainless steel samples of three different types were exposed to the effect of ion and oxygen free water at 20°C and 250°C. In the case of the low temperature (20°C) envirinment a ≈3 nm thick oxide layer could be observed, while the oxide layers developed at high (250°C) temperature treatment were thicker than 8 nm. Samples of the three alloys showed very different chromium enrichment in the oxide layer and chromium depletion in the uppermost layer of the bulk. Results obtained make it possible to follow the effect of a given corrosive environment on the surface, and help to select the proper alloy for this environment.

Surface and interface structures of PtSi samples were analysed by means of XPS depth profiling by using sequential Ar ion sputtering. Pt layers of 50 nm thickness were evaporated onto n-type Si wafers, then treated at temperatures in the region of 450–600°C in H 2 or O 2 atmospheres for 30–45 min. In the case of samples treated in O 2 , silicon can be identified in oxidized form at the Ptsilicide interfaces contrary to the samples treated in H 2 , where this interface is vanishing. In all cases SiO 2 is found to be present in the uppermost layer of the samples.

Results of surface analysis are presented, investigating the structure of passive layers developed on the surface of stainless steel tubes treated in a LWR (light water cooled nuclear reactor) primary circuit and tested in model experiments using different aqueous media and pretreatment methods. Ar + ion XPS depth profiles show remarkable differences in surface layer structure for different treatments.

Aerosol samples were collected from different densely populated areas of the town Debrecen (Hungary), involving the neighbourhood of potential air pollution emitters as well as of some residential areas. The particle size was limited to ⪅2–4 μm using a cascade impactor during sampling. Air pollutants collected were analysed by chemical and surface (bulk) analytical methods (XPS, PIXE, SEM, EPMA, IR). The results obtained show a much more detailed picture (regarding elemental and molecular composition as well as morphology) compared to routine monitoring by chemical methods. In the case of sulphur adsorbed on different (metal) surfaces sulphide was found by XPS to be dominating, contrary to the results of our earlier XPS analysis of aerosol ejected by a coal-fired power plant [L Kover and J Toth, Atmospheric Environ, 18, 2135 (1985)].