电解液中金属离子对高压光箔腐蚀行为影响的研究

Effect of metal ions in electrolyte on etching behavior of high-voltage anode aluminum foil

采用极化曲线和计时电位曲线考察了盐酸-硫酸电解液中金属离子对高压光箔腐蚀电化学行为影响,利用扫描电子显微镜(SEM)分析了金属离子对光箔腐蚀形貌和性能的影响.结果表明,电解液中单独添加Fe^3+或Cu^2+后,自腐蚀电位都正移,由于强的局部微电池效应,Cu^2+的影响相对Fe^3+更显著;单独添加Fe^3+后,击穿电位下降,而击穿电位随Cu^2+添加量的增加先增加后降低;Fe^3+对蚀孔形貌的影响与其浓度有关,峰值孔径随Fe^3+添加量的增加先增大后减小;而Cu^2+对峰值孔径影响较小,但会减少蚀孔密度;另外,添加少量Fe^3+有利于提升阳极箔520 V比容,从0.816×10^-6 F·cm^-2增加到0.828×10^-6 F·cm^-2,而添加Cu^2+会降低阳极箔性能.

The effect of metal ions in HCl-H2 SO4 electrolyte on the etching behavior of high-voltage aluminum foil was investigated with anodic polarization curve and potential transient measurement.The surface morphology and property of the etched foil was also analyzed by SEM.The results show that due to the strong Cu-Al galvanic effect,the self-corrosion potential after the addition of single Cu^2+shifts to more positive direction than that after the addition of single Fe^3+.The breakdown potential decreases with addition of single Fe^3+,however,the potential increases first and decreases afterward with addition of single Cu^2+.Furthermore,the impact of Fe^3+on the surface morphology of the foil depends on the concentration of Fe^3+,and the peak mean diameter increases initially and then decreases with increasing amount of Fe^3+.Cu^2+has slight impact on the peak mean diameter,whereas the pit density decreases.The specific capacitance at 520 V is enhanced from 0.816×10^-6 F·cm^-2to 0.828×10^-6 F·cm^-2with the trace addition of Fe^3+.However,the addition of Cu^2+leads to deteriorated specific capacitance.