The present work investigates the weathering process of glass surfaces with the formation of corrosion growth rings investigated by X-ray photoelectron spectroscopy, optical microscope, environmental ...scanning electron microscope and particle induced X-ray emission. The analysed samples are both ancient and recent glasses. The first set of samples is constituted by Roman glass fragments originally belonging to the load of the Iulia Felix ship, sunken in the Northern Adriatic sea (Grado, Italy) during II century AD. The samples were already investigated in the past F. Barbana, R. Bertoncello, L. Milanese, C. Sada, J. Non-Cryst. Solids 337 (2) (2004) 136; B. Dal Bianco, R. Bertoncello, L. Milanese, S. Barison, J. Non-Cryst. Solids 343 (2004) 91; B. Dal Bianco, R. Bertoncello, L. Milanese, S. Barison, Surface Eng. 21 (5–6) (2005) 393; B. Dal Bianco, R. Bertoncello, L. Milanese, S. Barison, Archaeometry 47 (2) (2005) 353, but their production process is still unknown. The second set of samples belongs to the stained window of S. Giovanni church in Polegge (Vicenza, Italy) and it is dated to 1930 ca. The glass production process is well known. In fact, every tessera is made of soda-lime glass. On one side only, the glass is coated with a green pigment (low melting temperature glass) and then heated in oven in order to fix it on the glass. The window is then mounted and fixed to the wall. Unfortunately, during this procedure, the window was positioned inside-out, so that the painted surface was exposed to the direct action of the atmospheric conditions. This anomaly favoured the fast degradation of the tessera, with the presence of concentric rings at the surface. Another set of samples was produced in order to simulate the effects of moisture at the glass surface, using an industrial soda-lime glass and coating it with a painting originally used in 1930s. The comparisons between the corrosion of the three sets of samples suggest that the Iulia Felix glasses could have been prepared with the same technique.
Ancient glasses deriving from differing environments (marine and ground) and areas (Mediterranean and Continental) have been investigated to understand their weathering processes. Although the glass ...technologies, developed in various ways, and the differing compositions of the glasses from the two areas, have generated differing durabilities, the weathering features of both typologies of glass are identical. Therefore, the corrosion phenomena are due to the action of water, and they are not related to the sample microclimate. Data have been collected using optical microscopy, RGA and surface analysis techniques: XPS, ESEM and SIMS.
Lead silicate glasses (45.3 weight % of lead oxide) were leached in aqueous static solutions of HNO3 at pH=2 and T=90 C for different leaching times, to study the weathering mechanism of lead glasses ...in an acidic environment.
Gallium oxide thin films were deposited on alumina and TiO
2 substrates by metal organic chemical vapour deposition using gallium trishexafluoroacetylacetonate (Ga(hfac)
3) as precursor in the ...presence of oxygen. The depositions were carried out at 470°C and 2.6 kPa leading to a growth rate of 0.7 μm h
−1. As-grown films appeared black, smooth and well adherent to the substrates. X-Ray photoelectron spectroscopy (XPS) analysis revealed stoichiometric Ga
2O
3 with a low carbon content (less than 5%) and almost undetectable fluorine. As-deposited Ga
2O
3 films were X-ray amorphous, but the onset of a crystallization process was evident after annealing in dry air at 700 °C. Moreover, after thermal treatment, the films became carbon free and transparent in the visible range. The effect of annealing at different temperatures on the film structure was investigated by X-ray diffraction. A phase modification from amorphous to polycrystalline Ga
2O
3 was observed after thermal treatment at temperatures from 600 to 1000 °C. As shown by secondary ion mass spectrometry (SIMS) studies, Al diffusion into Ga
2O
3 films was detected after annealing at 1000 °C when pure Al
2O
3 was used as substrate; this diffusion was completely inhibited using a TiO
2 film as buffer layer with a thickness of at least 4 μm.
PbO
2+Co
3O
4, Tl
2O
3+Co
3O
4 and Ni+Co
3O
4 composite layers have been obtained by either anodic (oxide matrices) or cathodic (Ni-matrix) electrodeposition. Their electrocatalytic activity in the ...oxygen evolution reaction has been investigated with the aim of assessing the effect of concentration of Co
3O
4 and surface roughness. Different composites showed a different dependence of oxygen evolution current density on Co
3O
4 content. Only in the case of PbO
2+Co
3O
4, the electrode effective area appeared to increase with the dispersed phase concentration, resulting in a non-linear relationship between oxygen evolution rate and Co
3O
4 content.
Peculiarities and application perspectives of metal-ion implants in glasses
Nuclear instruments and methods in physics research. Section B, Beam interactions with materials and atoms/Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms
Journal Article
Roman glass surfaces have been studied to understand water effects on glass degradation and ionic mobility. Studied specimens mainly come from the Roman ship Iulia Felix, found on the seabed of Grado ...lagoon (Italy) and dated to the 2nd century AD. Many different corrosion features have been investigated including white glass, glossy glass and growth rings. A typical multilayered structure found in glass is characterised by the presence of different ions in depth profiles. Layered structure is also underlined by variations in hydration oxygen value and adventitious carbon content. Evidence of ion mobility can be found in the study of growth rings, which have metal rich centres rounded with concentric rings. The centres are characterised by the presence of antimony and titanium in their maximum oxidation state: Sb(V) and Ti(IV). The evolution can be understood according to 'Liesegang ring' kinetics. Data of glass surfaces have been collected using many techniques, i.e. X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS) and environmental scanning electron microscopy (ESEM). Several bulk techniques to characterise the specimens have been used.
Cluster formation is studied after sequential double implantation (Cu, Ni; Ag, S) in silica and soda–lime glass. The structure and properties of nanocluster composites are investigated by optical ...absorption spectroscopy and transmission electron microscopy, evidencing the formation of core-shell structures. The presence of metal alloy clusters is also investigated by means of synchrotron-radiation-based techniques.
Structural and chemical investigations on electrodeposited nickel-phosphorous alloy coatings by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy ...(SIMS) are described. Electrodeposition of nickel-phosphorous coatings has been carried out galvanostatically in a hypophosphite bath at two different current densities, namely 20 and 80 mA cm
−2. XRD has shown a broad peak indicating an amorphous structure in both cases. XPS shows the presence of Ni
2P compound. XPS also reveals the amount of phosphorous in both coatings to be around 10.20 wt.%. SIMS has shown that the coating deposited at lower current densdity (20 mA cm
−2) has a broad coating-substrate interface, possibly due to some porosity in this coating. The presence of some oxygen contamination at the coating-substrate interface is also evidenced through SIMS in both cases. The usefulness of XPS and SIMS in the characterization of electrodeposited coatings is demonstrated.
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