Electrochemical modification of Bi2S3 coatings in a nickel plating electrolyte

Autor: Leonas Naruškevičius, Birutė Šimkūnaitė, Genovaitė Valiulienė, Vidas Pakštas, Loreta Tamašauskaitė Tamašiūnaitė, Albina Žielienė, Algis Selskis
Rok vydání: 2009
Předmět:
Zdroj: Journal of Solid State Electrochemistry. 14:203-212
ISSN: 1433-0768
1432-8488
DOI: 10.1007/s10008-009-0792-7
Popis: The electrochemical behavior of Bi2S3 coatings in Watts nickel plating electrolyte was investigated using the cyclic voltammetry, electrochemical quartz crystal microbalance, X-ray diffraction, and energy dispersive X-ray analysis methods. During the bismuth sulfide coating reduction in Watts background electrolyte in the potential region from −0.4 to −0.6 V, the Bi2S3 and Bi(III) oxygen compounds are reduced to metallic Bi, and the decrease in coating mass is related to the transfer of S2− ions from the electrode surface. When the bismuth sulfide coating is reduced in Watts nickel plating electrolyte, the observed increase in coating mass in the potential region −0.1 to −0.4 V is conditioned by Ni2+ ions reduction before the bulk deposition of Ni, initiated by Bi2S3. In this potential region, the reduction of Bi(III) oxygen compounds can occur. After the treatment of as-deposited bismuth sulfide coating in nickel plating electrolyte at E = −0.3 V, the sheet resistance of the layer decreases from 1013 to 500–700 Ω cm. A metal-rich mixed sulfide Ni3Bi2S2–parkerite is obtained when as-deposited bismuth sulfide coating is treated in Watts nickel plating electrolyte at a potential close to the equilibrium potential of the Ni/Ni2+ system and then annealed at temperatures higher than 120 °C.
Databáze: OpenAIRE
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