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The paper presents the difference of three varied methods which have been used to analyze archaeological metals: X-ray fluorescence analysis – XRF (X-ray spectrometer), energy dispersive X-Ray microanalysis – EDAX (electron microscopy), and inductively coupled plasma mass spectrometry (MS-ICP). Illustrative examples of different measurements are two fragments of sickles from the hoard near the village of Sosnovaya Maza and three plates of horse harness from the treasure from the territory of the Republic of Crimea. The analysis of the results reveals the importance of formulation an individual methodology for analysis and the process of sample preparation for each measured object.

A detailed study of the structure, morphology and electrochemical properties of Pt/C and Pt/x-SnO2/C catalysts synthesized using a polyol method has been provided. A series of catalysts supported on the SnO2-modified carbon was synthesized and studied by various methods including transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical methods, and fuel cell testing. The SnO2 content varies from 5 to 40 wt %. The TEM images, XRD and XPS analysis suggested the Pt-SnO2 hetero-clusters formation. The SnO2 content of ca. 10% ensures an optimal catalytic layer structure and morphology providing uniform distribution of Pt-SnO2 clusters over the carbon support surface. Pt/10wt %-SnO2/C catalyst demonstrates increased activity and durability toward the oxygen reduction reaction (ORR) in course of accelerated stress testing due to the high stability of SnO2 and its interaction with Pt. The polymer electrolyte membrane fuel cell current–voltage performance of the Pt/10wt %-SnO2/C is comparable with those of Pt/C, however, higher durability is expected. [ABSTRACT FROM AUTHOR]

This article is devoted to further development of magnetron sputtering technology for catalysts and catalysts layer production for fuel cells and other electrochemical devices. Platinum-carbon films with Pt content up to 95–97 wt % were deposited using different sputtering regimes—DC (direct current) sputtering with and without application of a pulse negative bias voltage to the titanium substrate and also bipolar pulse sputtering with frequency of 10 kHz and 100 kHz. Composite platinum carbon targets were used for sputtering. Characteristics of platinum-carbon films were compared with those of platinum films deposited using the same regimes. The main methods of investigation were scanning transmission electron microscopy (STEM) with energy dispersive X-ray spectroscopy; potentiostatic and potentiodynamic methods. The catalytic activity of platinum-carbon films increased with platinum content and at a platinum concentration of 95–97 wt % became higher than that of platinum films sputtered in the same regimes. It was proposed that carbon atoms deposited on the substrate limited the mobility of the deposited platinum species and inhibited Pt cluster growth. Platinum-carbon films produced by pulsed DC magnetron sputtering with pulsed frequency 100 kHz consisted of narrow Pt columns with dome nanotops forming a well-developed surface. The porosity and specific surface of these columnar nanopillar films were higher compared with those of pure platinum films deposited under the same conditions. Moreover, the platinum-carbon films deposited using a bipolar pulse regime with a frequency of 100 kHz had the highest specific surface, porosity (30%) and catalytic activity in hydrogen and oxygen evolution due to a high ion current density and reduced pulse duration which inhibited the growth of large platinum globules. [ABSTRACT FROM AUTHOR]