The characterisation of the protective film formed by benzotriazole on the 90/10 copper-nickel alloy surface in H2SO4 media
Nenhuma Miniatura disponível
Data
2008-03-01
Autores
Maciel, Jose Maria
Vera Villamil Jaimes, Ruth Flavia
Corio, Paola
Rubim, Joel Camargo
Volpe, Pedro Luis
Agostinho Neto, Augusto [UNESP]
Leite Agostinho, Silvia Maria
Título da Revista
ISSN da Revista
Título de Volume
Editor
Pergamon-Elsevier B.V. Ltd
Resumo
The nature of the protective film formed by benzotriazole (BTAH) on the surface of the 90/10 CuNi alloy in deaerated 0.5 mol L-1 H2SO4 solution containing Fe(III) ions as oxidant was investigated by weight-loss, calorimetric measurements, and by surface-enhanced Raman spectroscopy (SERS). The SERS measurements show that the protective film is composed by the [Cu(I)BTA](n), polymeric complex and that the BTAH molecules are also adsorbed on the electrode surface. A modification of the BET isotherm for adsorption of gases ill solids is proposed to describe the experimental results obtained from weight-loss experiments that suggest an adsorption in multilayers. Electrochemical studies of copper and nickel in 0.5 mol L-1 H2SO4 in presence and absence of BTAH have also been made as an aid to interpret the results. The calculated adsorption free energy of the cuprous benzotriazolate on the surface of the alloy is in accordance with the value for pure copper. (C) 2007 Elsevier Ltd. All rights reserved.
Descrição
Palavras-chave
benzotriazole, copper-nickel alloys, corrosion inhibitors, Raman spectroscopy, adsorption isotherms
Como citar
Corrosion Science. Oxford: Pergamon-Elsevier B.V. Ltd, v. 50, n. 3, p. 879-886, 2008.