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Since ancient times, the use of high-tin bronze alloys (>17 wt.%) has been mainly limited to the production of specific objects such as mirrors and bells. High-tin bronzes can show distinctive colour reflection, as well as mechanical properties and corrosion resistance that clearly distinguish them from the classical bronze composition (with 8–12 wt.% tin). In the present study samples of archaeological high-tin bronze bells were studied by optical microscopy, SEM-EDX, and Raman imaging with the aim of characterising their microstructural long-term corrosion patterns. Results show the presence of high quantities of δ phase, when compared to the classical bronze composition, which makes some corrosion structures more visible in these alloys. The corrosion morphologies show selective corrosion of different metal phases along depth of corrosion, which were attributed to different oxygen potentials. This study proposes a classification of four types of corrosion structures occurring in two-phase bronzes as a consequence of aeration conditions during burial time and aeration within the corrosion structure. [ABSTRACT FROM AUTHOR]

We report the effect of a disperse carbon interlayer between the n-a-Si:H layer and an aluminium zinc oxide (AZO) back contact on the performance of amorphous silicon solar cells. Carbon was incorporated to the AZO film as revealed by x-ray photoelectron spectroscopy and energy-dispersive x-ray analysis. Solar cells fabricated on glass substrates using AZO in the back contact performed better when a disperse carbon interlayer was present in their structure. They exhibited an initial efficiency of 11%, open-circuit voltage Voc = 1.6 V, short-circuit current JSC = 11 mA cm−2 and a filling factor of 63%, that is, a 10% increase in the JSC and 20% increase in the efficiency compared to a standard solar cell. [ABSTRACT FROM AUTHOR]

We have characterized the structure and electrical properties of p-type nanocrystalline silicon films prepared by radio-frequency plasma-enhanced chemical vapor deposition and explored optimization methods of such layers for potential applications in thin-film solar cells. Particular attention was paid to the characterization of very thin (&#876420 nm) films. The cross-sectional morphology of the layers was studied by fitting the ellipsometry spectra using a multilayer model. The results suggest that the crystallization process in a high-pressure growth regime is mostly realized through a subsurface mechanism in the absence of the incubation layer at the substrate-film interface. Hydrogen plasma treatment of a 22-nm-thick film improved its electrical properties (conductivity increased more than ten times) owing to hydrogen insertion and Si structure rearrangements throughout the entire thickness of the film. [ABSTRACT FROM AUTHOR]

We have characterized the structure and electrical properties of p-type nanocrystalline silicon films prepared by radio-frequency plasma-enhanced chemical vapor deposition and explored optimization methods of such layers for potential applications in thin-film solar cells. Particular attention was paid to the characterization of very thin (&#876420 nm) films. The cross-sectional morphology of the layers was studied by fitting the ellipsometry spectra using a multilayer model. The results suggest that the crystallization process in a high-pressure growth regime is mostly realized through a subsurface mechanism in the absence of the incubation layer at the substrate-film interface. Hydrogen plasma treatment of a 22-nm-thick film improved its electrical properties (conductivity increased more than ten times) owing to hydrogen insertion and Si structure rearrangements throughout the entire thickness of the film. [ABSTRACT FROM AUTHOR]