银盘电极上的示波计时电位法

Oscillographic chronopotentiometry based on dE/dt-t at silver disk electrode

首次将银盘电极用于示波计时电位法直接进行示波测定 ,讨论了银盘电极上的示波计时电位法。银盘电极制备简单 ,寿命长 ,使用时不需镀汞 ,无污染。与用汞膜电极的示波计时电位法相比 ,银盘电极上的示波计时电位法具有图形稳定、灵敏度高、精密度好及测定的线性范围宽等优点。通过对 Pb2 + ,Zn2 + ,In3 + 3种离子的定量测定表明 ,检测下限在 1 0 -9～ 1 0 -7mol/L之间。对自来水样中痕量 Pb2 + 进行分析 。

The use of silver disk electrode for oscillographic chronopotentiometry is described. Silver disk electrode exhibits long term stability, and no use for mercury. Compared with mercury film electrode, oscillographic chronopotentiometry at silver disk electrode has fine sensitivity and precision. By using it, determined a series of ions such as Pb 2+ ,Zn 2+ ,In 3+ .For tap water a mean value of 4.23 μg/L Pb 2+ was found, which agreed with anodic stripping voltammetry of the hanging mercury drop electrode (HMDE).The relative standard deviation for Pb 2+ is 4.8%( n =5).