In this contribution we report on an XPS study of microporous and mesoporous titanosilicates, in particular microporous titanium silicalite TS-1, ordered mesoporous Ti-MCM-41 and [Ti]-MCM-41 and amorphous mesoporous silica-titania (MST) catalysts. Our aim was to obtain both photoemission and x-ray-excited Auger data for Ti species on these catalysts and use them in a Ti Wagner plot to rationalize the dependence of the local electronic structure on the atomic environment. Isolated Ti(IV) species coordinated to four and six oxygen anions and segregated TiO2 clusters were detected on all catalysts by a curve-fitting procedure of Ti 2p, O 1s and related peaks. The presence of the Si 2p peak excited by an O Kalpha ghost makes the detection of Ti LMM Auger transitions in mesoporous samples impossible due to the low Ti loadings and its homogeneous distribution in the silica matrix. Small TiO2 clusters are eventually segregated within the mesopores of the catalysts and not at their external surface. On TS-1 microporous catalysts with similar Ti loadings to the mesoporous catalysts we were able to detect Ti LMM Auger transitions, and by the Ti Wagner plot we clearly identify the presence of octahedrally coordinated Ti(IV) species. Thus, it is suggested that on TS-1 the in-framework (-O)(4)Ti species are easily changed to (-O)(4)(H2O)(2)Ti species by insertion of water molecules from the atmosphere. Small TiO2 clusters (diameter <5 nm), eventually present on samples with Ti loading >2 wt.%, are segregated at their external surface and present spectroscopic features similar to (-O)(4)(H2O)(2)Ti species. Copyright (C) 2004 John Wiley Sons, Ltd

Following a previous investigation on micro-and mesoporous titanosilicates, we have here deepened the XPS and Xray-excited Auger electron spectroscopy (XAES) studies on the surface properties of microporous titanosilicalites-1 (TS-1) and reference silicalites-1 (S-1), both characterized by the MFI framework type. The aim was that of complementing the information already obtained on these compounds with other techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), dielectric relaxation spectroscopy (DRS), electron spin resonance (ESR), and quantomechanical calculations. Notwithstanding the expected low photoelectron intensity due to the very low solubility of Ti (IV) ions in the MFI framework, an accurate XPS curve-fitting procedure and the simultaneous use of the XPS and Auger signals (Wagner plot) have made possible, both qualitatively and quantitatively, the distinction of two Ti (IV) sites: the framework tetrahedral species -Ti (IV) substituting Si (IV) -and the Ti(IV) tetrahedral species grafted to surface hydroxyl groups. Both species are prone to convert into octahedrally coordinated Ti (IV) species as a consequence of interaction with water and other ligands.

Limestone basements holding bronzes or other copper alloys artefacts such as sculptures, decorations and dedicatory inscriptions are frequently met both in modern and ancient monuments. In outdoor conditions, such a combination implies the corrosion products of the copper based alloy, directly exposed to rainwater, will be drained off and migrate through the porous surfaces, forming stains of different colours and intensities, finally causing the limestone structures to deteriorate.In this work we have analysed samples from two modern limestone monuments in Rome, the Botticino surfaces of the ‘Vittoriano’ (by G.Sacconi, 1885-1911- Piazza Venezia) and the travertine basement of the ‘Statua dello Studente’ (by A.Cataldi, 1920- University city, La Sapienza), and focussed our investigation on the chemical composition of the copper-stained zones using XPS (X-ray Photoelectron Spectroscopy) as a surface-specific technique.Based on observations reporting on the structure and bonding at the calcite surfaces we have identified copper complexes and mixed calcium/copper carbonates associated with the stains, as well as the chemical state of other elements therein included, and related the compositional changes with differences in chromatic characteristics and sampling locations.

The aim of this study was to determine the effect of UV-C irradiation on the Turkey oak wood surface (Quercus cerris L.). In order to compare the effect of irradiation, both untreated wood samples and those treated with steam and heat were analyzed. The steam treatments were carried out in an autoclave at 130 °C; samples were then heated in an oven for 2 h at 180 °C. The physical and chemical changes brought about in the untreated and treated wood samples by the UV-C light were monitored by colorimetry (color changes), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) (chemical composition) and scanning electron microscopy (SEM) (microstructure and morphology). A detailed analysis of the results indicates that the UV-C treatment caused irreversible changes in both the chemical composition and morphology of the wood samples via photooxidation and photodegradation processes. Depending on the type of pre-treatment used, these processes affected the wood samples differently

In the last few years much progress has been made in the development of hybrid polymer–inorganic filler nanocomposites. Nevertheless, many questions remain. The comprehension of the structure and the interactions at the polymer–nanofiller interface are crucial to foresee and control the properties of nanocomposites. Because of the high surface ratio of the inorganic nanofiller, the interface is expected to have a prevailing role in determining the nanocomposite properties. In this study we use X‐ray photoelectron spectroscopy (XPS) as a tool for the surface characterization of an organophilic montmorillonite/poly(ε‐caprolactone) exfoliated nanocomposite. The XPS core levels of the nanocomposite have been compared with those obtained from its precursors, and analyzed as reference compounds to evaluate eventual differences attributable to the polymer–nanofiller interfacial interactions. The XPS investigation has allowed us to propose a qualitative model of possible interface interactions between poly(ε‐caprolactone) and the organo‐modified montmorillonite. The model is substantiated by Fourier transform infrared spectroscopy (FTIR). © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3907–3919, 2004