Platinum-titanium dioxide alloys

The DSA-type anodes are inert , coated anodes made of a valve metal (titanium, niobium, or tantalum) base coated with an electrochemically active coating. The active coating is made either of noble metals or of mixed metal oxides. Noble metals in active coatings are usually platinum or platinum alloys. Mixed metal-oxide coatings contain active oxides and inert oxides the active components are usually ruthenium dioxide (R.UO2) and iridium dioxide (IrC>2) and the inert components are mostly titanium dioxide (TiC>2) and other oxides such as tantalum... 

Lead materials lead-antimony-silver, lead with platinum alloy microelectrodes, lead/magnetite, lead dioxide/titanium, lead dioxide/ graphite. 

The insertion of platinum microelectrodes into the surface of lead and some lead alloys has been found to promote the formation of lead dioxide in chloride solutions" " . Experiments with silver and titanium microelectrodes have shown that these do not result in this improvement". Similar results to those when using platinum have been found with graphite and iridium, and although only a very small total surface area of microelectrodes is required to achieve benefit, the larger the ratio of platinum to lead surface, the faster the passivation". Platinised titanium microelectrodes have also been utilised. 

Metal oxide coatings Commercial lead dioxide coatings, for example, on titanium, have a higher stability compared with lead or lead alloy anodes with their in situ formed oxide layer. A secure contact between Pb02 and titanium has to be guaranteed, for example, by a platinum layer or at least by a sufficiently large number of platinum crystallites. 

Use Hardener for platinum and palladinum in jewelry, electrical contact alloys, catalyst, medical instruments, corrosion-resistant alloys, electrodeposited coatings, nitrogen-fixing agent (experimental), solar cells (experimental) the oxide is used to coat titanium anodes in electrolytic production of chloride the dioxide serves as an oxidizer in photolysis of hydrogen sulfide. 

For the analysis of titanium and titanium alloys, on the other hand, ASTM (150) suggests two vacuum processes the first, which originates from Hansen et al. (128), uses platinum, the second, first described by Walter (113), uses tin as a flux metal (in a 10 1 ratio with Ti). In both cases, the carbon dioxide formed is frozen out with liquid nitrogen, and determined volumetrically in the form of gas. The sample (approx. 250 mg) and the flux metal are inserted together into the crucible, but not in the form of a sandwich. The temperature of the analysis is 1950°C. The crucible is degassed at 2400°C by induction heating and the range of application is 300 to 5000 Atg/g. 

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