摘要
通过集气、动电位极化曲线、恒流放电、扫描电镜和X射线能谱等方法研究了纯铝在含有锡酸钠的4mol·L-1氢氧化钾的甲醇-水(甲醇和水的体积比为4∶1,下同)混合溶液中的腐蚀和阳极溶解行为.实验结果表明,锡酸钠的添加通过具有较高析氢过电位的金属锡在电极表面的沉积,极大地抑制了铝在4mol·L-1氢氧化钾的甲醇-水溶液中的腐蚀;而由于在锡沉积层中裂纹的出现,导致较大浓度锡酸钠的缓蚀作用有所降低.恒流放电结果表明,铝在含有锡酸钠的4mol·L-1氢氧化钾的甲醇-水溶液中的恒流放电性能明显改进,而且铝阳极的放电性能随着锡酸钠含量的增大而逐渐提高.在20mA·cm-2的放电电流密度下,铝阳极在含有10.0mmol·L-1锡酸钠的电解液中显示了电位相对较低且较平坦的放电平台.
The corrosion and anodic dissolution behaviors of pure aluminum in Na2SnO3-containing 4 mol· L^-1 KOH methanol-water mixed solutions with a methanol/water volume ratio of 4：1 were investigated. This was carded out by means of hydrogen collection, polarization curve, galvanostatic discharge, scanning electron microscopy （SEM）, and energy dispersive analysis of X-ray （EDAX）. The experimental results indicated that the addition of stannate inhibited the corrosion of aluminum in the 4 mol ·L^-1 KOH methanol-water solutions by the deposition of tin with a higher hydrogen evolution overpotential on the electrode surface. In the electrolytes with higher stannate contents the inhibiting effect decreased because of the occurrence of some cracks on the tin deposition film. The results of galvanostatic discharge showed that the discharge of aluminum in the Na2SnO3-containing 4 mol·L^-1 KOH methanol-water solutions were obviously improved. In addition, the improvement effect enhanced with the increase of stannate content. It was noted that the aluminum anode showed a very flat discharge plateau at relatively low potentials in the electrolyte with 10.0 mmol·L^-1 Na2SnO3 at 20 mA·cm^-2 discharge current density.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2008年第9期1620-1624,共5页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(50571091)资助项目
