采用非现场表面增强拉曼光谱（ex-situ SERS）与电还原等方法，对2，3-二巯基丁二酸（DMSA）及与Ni（Ⅱ）所形成的配位化合物DMSA-Ni（Ⅱ），在活性Au电极表面的修饰膜进行了研究。先由紫外吸收光谱测算了DMSA与Ni2＋形成的配合物参数，其配位比为1∶2，稳定常数为4.716×107，可知形成的配合物较稳定。研究表明，DMSA与活性Au发生了吸附作用，DMSA-Ni（Ⅱ）形成的是S—Ni—O配位键，DMSA-Ni （Ⅱ）在Au电极上电还原时出现了两个还原峰，认为：负扫出现的第1个还原峰是由DMSA-Ni（Ⅱ）配合物动态平衡中的DMSA与Au吸附键合的RS—Au基团产生，而第2个还原峰与配合物中的Ni2＋有关。通过Au表面DMSA-Ni（Ⅱ）修饰膜覆盖度的测定、分子面积的比对表明，DMSA-Ni（Ⅱ）在活性Au表面的分子排布状态可能是分散的或局部连接的单分子层，而非聚集在一起的致密层或分子间重叠的多层形式。%2 ,3-Dimercaptosuccinic acid (DMSA) and its complex Nickel(Ⅱ) 2 ,3-Dimercaptosuccinate (DMSA-Ni(Ⅱ)) were as-sembled on the electrochemically activated Au electrode and the modified films were investigated by ex-situ SERS ,SEM and elec-tro-reduction .The coordination ratio (1∶2) and stability constant (4.716 × 107 ) of DMSA and Nickel(Ⅱ ) were firstly con-firmed by UV .Then ,the SERS spectra showed that DMSA was absorbed on the surface of activated Au and the coordinate bond of DMSA-Ni(Ⅱ) was existed as S—Ni—O .Meanwhile ,two reduction peaks of DMSA-Ni(Ⅱ) on Au electrode were presented at negative potential .The first peak (from positive to negative values) was related to the RS—Au group which was produced by the mutual absorption of DMSA and Au .The second reduction peak was related to Nickel (Ⅱ) .Finally ,it was further confirmed by calculating the surface coverage and comparison of molecular area .And it was found that the molecular arrangement of DM-SA-Ni(Ⅱ) on Au electrode generated as monolayer which was dispersed or connected partly instead of concentrated or over-lapped .
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