Gold deposition from 1-butyl-1-methyl-pyrrolidinium dicyanamide ionic liquid at open-circuit and under potentiostatic control

• Autor(a) principal: Sá, A.I. De
• Data de Publicação: 2013
• Outros Autores: Eugénio, S., Quaresma, S., Rangel, C. M., Vilar, R.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.9/1992
• topic: Gold; Electrodeposition; Ionic liquids; Open-circuit deposition

In this work, the deposition of gold on copper substrates from solutions of HAuCl4.3H2O in 1-butyl-1-methylpyrrolidinium dicyanamide was studied. Deposition was carried out in open-circuit and under potentiostatic control at temperatures from 293 to 353 K, in normal atmosphere, with deposition conditions allowing water from atmospheric absorption up to 0.8 wt.%. Films of gold were obtained by both methods. Deposition at open-circuit occurs by galvanic displacement mechanism. Involvement of Cu+ species in the electrodeposition process was suggested by cyclic voltammetry. Furthermore, copper incorporation in the gold films was confirmed by X-ray diffraction. SEM observation and XRD analysis show that films are nanocrystalline with a globular morphology except for the films formed under potentiostatic control at 353 K, which show a dendritic structure. The size of the crystallites determined by Scherrer's equation varies in the range from 6 to 25 nm.