Influence of alkylpyridinium ionic liquids on copper electrodeposition from acidic sulfate electrolyte
来源期刊：中南大学学报(英文版)2013年第8期
论文作者：ZHANG Qi-bo(张启波) HUA Yi-xin(华一新) REN Yan-xu(任艳旭) CHEN Li-yuan(陈立源)
文章页码：2096 - 2102
Key words：copper electrodeposition; additives; ionic liquids; electrokinetic parameter; adsorption
Abstract: The effect of two alkylpyridinium ionic liquids (py-iLs) including N-butylpyridinium hydrogen sulfate (BpyHSO4) and N-hexylpyridinium hydrogen sulfate (HpyHSO4) on the kinetics of copper electrodeposition from acidic sulfate solution was investigated by cyclic voltammetry and potentiodynamic polarization measurements. Results from cyclic voltammetry indicate that these py-iLs have a pronounced inhibiting effect on Cu2+ electroreduction and there exists a typical nucleation and growth process. Kinetic parameters such as Tafel slope, transfer coefficient and exchange current density obtained from Tafel plots, lead to the conclusion that py-iLs inhibit the charge transfer by slightly changing the copper electrodeposition mechanism through their adsorption on the cathodic surface. In addition, scanning electron microscope (SEM) and X-ray diffraction analyses reveal that the presence of these additives leads to more leveled and fine-grained cathodic deposits without changing the crystal structure of the electrodeposited copper but strongly affects the crystallographic orientation by significantly inhibiting the growth of (111), (200) and (311) planes.
ZHANG Qi-bo(张启波), HUA Yi-xin(华一新), REN Yan-xu(任艳旭), CHEN Li-yuan(陈立源)
(Faculty of Metallurgical and Energy Engineering,
Kunming University of Science and Technology, Kunming 650093, China)
Abstract:The effect of two alkylpyridinium ionic liquids (py-iLs) including N-butylpyridinium hydrogen sulfate (BpyHSO4) and N-hexylpyridinium hydrogen sulfate (HpyHSO4) on the kinetics of copper electrodeposition from acidic sulfate solution was investigated by cyclic voltammetry and potentiodynamic polarization measurements. Results from cyclic voltammetry indicate that these py-iLs have a pronounced inhibiting effect on Cu2+ electroreduction and there exists a typical nucleation and growth process. Kinetic parameters such as Tafel slope, transfer coefficient and exchange current density obtained from Tafel plots, lead to the conclusion that py-iLs inhibit the charge transfer by slightly changing the copper electrodeposition mechanism through their adsorption on the cathodic surface. In addition, scanning electron microscope (SEM) and X-ray diffraction analyses reveal that the presence of these additives leads to more leveled and fine-grained cathodic deposits without changing the crystal structure of the electrodeposited copper but strongly affects the crystallographic orientation by significantly inhibiting the growth of (111), (200) and (311) planes.
Key words:copper electrodeposition; additives; ionic liquids; electrokinetic parameter; adsorption
