Wear-Resistant Nanostructured Platinum-Titanium Anodes: I. STM and STS Measurements on Model ECAPTA Specimen

摘要

The history of developing technology for producing wear-resistant anodes for the electrochemical industry in the middle of 20th century in Russia, which resulted in the creation of the first effective nanoma-terials, is briefly overviewed. These anodic materials, which operate under severe anodic polarization conditions, were obtained by applying a coating whose nanometer-thick surface layer had the necessary electrocat-alytic properties to a corrosion-resistant titanium substrate. One of the first of these materials was the ECAPTA platinum-titanium anode produced by the waste-free electrocontact alloying of the titanium surface with platinum. The electrodes are most effective in electrochemical processes that are not related to the production of oxidizers, as well as in galvanic and other technological processes. On one of the Russian plants, these anodes have already been operation for over 30 years without failure, although the whole original 2-um platinum coating layer formally dissolved in the first 2-2.5 years (judging from the data of weighing). Investigations are carried out using scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) in order to clarify the nature of the surface properties of the anodes and find the most efficient techniques for modifying the electrode materials to increase their electrocatalytic activity, as well as to improve the energy efficiency and increase the resource-saving of the production cycle, which determines the mechanism of formation of a stable corrosion-resistant surface that is electrocatalyticalfy active in a peculiar technological process. In part I, the results of studying the primary properties of the coatings on a model specimen (no. 1) are considered. In part II, the properties of a specimen upon the many-hour anodic polarization (no. 2) and those of a fragment cut from the industrial anode operated for many years (no. 3) are analyzed.