图 2（a）显示了纯 Zn 浸入r-SBF 不同时间后的 PDP 曲线。 除了 0 小时和 6 小时外，阳极分支显示出几乎相同的趋势，这表明类似钝化的区域和加速到高溶解速率。 阴极域包括一个几乎垂直的阶段直到-1.2 V_SCE 和一个斜坡区域（主要范围从-1.2 V_SCE 腐蚀电位），分别对应于氢气产生过程和氧气消耗过程。 从PDP曲线获得的相关参数E_corr，I_corr和β_c如表2所示。纯Zn的Ecorr值随着浸入的发展变化不大。 尽管如此，I_corr 值在浸入过程中经常波动，这在图 2（b）中可以清楚地看到。

Fig. 2(a) shows the PDP curves of pure Zn after immersion in r-SBF for different amount of time. The anodic branches showed nearly the same trend with the exception of 0 h and 6 h, which revealed passivation-like regions and acceleration to high dissolution rate. The cathodic domain included an almost vertical stage up to −1.2 V_SCE and a slope region (mainly ranging from −1.2 V_SCE to corrosion potential), which were corresponding to hydrogen generation process and the oxygen consumption process, respectively. The related parameters, E_corr, I_corr and β_c, obtained from the PDP curves were shown in Table 2. The E_corr values of pure Zn did not change much as the immersion evolves. Neertherless, the I_corr values frequently fluctuated during the immersion, which can be seen clearly in Fig. 2(b).