화학공학소재연구정보센터
Electrochimica Acta, Vol.55, No.8, 2829-2834, 2010
Effect of bromide ions on the corrosion behavior of tantalum in anhydrous ethanol
The electrochemical behaviors of Ta in Et4NBr ethanol solutions were investigated using potentiodynamic polarization, cyclic voltammetry, potentiostatic current-time transient and impedance techniques. The potentiodynamic anodic polarization curves did not exhibit active dissolution region due to the presence of thin oxide film on the electrode surface, which was followed by pitting corrosion as a result of passivity breakdown by the aggressive attack of Br- anions. The pitting potential (E-b) decreased with the increase of solution temperature and Br- concentration, but increased with increasing potential scan rate and water concentration. The incubation time derived from potentiostatic current-time transients decreased with increasing potentials. The impedance spectra exhibited two time constants for all the potentials and the resistance of passive layer decreased with increasing potential. (C) 2010 Elsevier Ltd. All rights reserved.