Tokareva I. Electrochemical synthesis of the porous oxide coatings on niobium

Object of study: the electrochemical processes occurring during the formation of oxide coatings on niobium. Aim of the study: the technology development of electrochemical synthesis of the porous oxide on niobium with given functional properties and the creation of the metal oxide electrode based on Nb-Nb2O5 system. Methods: linear voltammetry, scanning electron microscopy, X-ray fluorescence and X-ray phase analysis, electrochemical impedance spectroscopy, gravimetry. Theoretical and practical results: the technological process of electrochemical formation of porous oxide coatings on niobium is developed and the metal oxide electrode is created based on the synthesized niobium oxide system. Scientific novelty: the kinetic lows of niobium anodic oxidation in the acidic sulphate and sulphate-fluoride solutions are determined; the technological regimes (electrolyte composition, electrolysis parameters) that allow to get porous coatings of different morphology and structure on niobium are developed; the porous oxide coating of crystalline structure is found to be more corrosion resistant than the coating of X-ray amorphous; it is proved that niobium oxide system with porous oxide coating of crystalline type is characterized by stability of the electrode potential in a wide range of media pH. Degree of implementation: the developed reference electrode models passed long-term experimental-industrial tests in ScPE "Electromontazsh" (Kharkiv). Application area: instrument-making industry, oil and gas industry, municipal engineering; electrochemical production technology; at the research institutes and educational process.