对羟基苯硫酚自组装膜修饰金电极的制备及电化学表征

摘要

The 4-hydroxy thiol phenol self-assembled monolayers were prepared on the surface of gold electrode and a hydroxylated surface was constructed.In the optimized experimental conditions,electrochemical impedance spectroscopy was used to track the film-forming process of the 4-hydroxy thiol phenol（4-HTP） on the surface of gold electrodes.The equivalent circuit of Randles was used to simulate impedance complex plan,then the equivalent circuit of system and electrochemical parameter was determined.Based on the relationship between charge transfer resistance（Rct） and assembled time,the adsorption dynamic curve of 4-HTP on Au electrode can be obtained.The results showed that Rct decreased rapidly with increasing assembled time,which demonstrated that 4-HTP SAM is a conductive film.When assembled time reached to 120 min,4-HTP SAM reached adsorption equilibrium,Rct no longer changed.This approach may be useful in the research of SAMs and biosensors.%在金电极表面制备了对羟基苯硫酚（4-HTP）自组装单分子膜,构建了一种羟基化金电极表面.在优化实验条件下,利用交流阻抗技术对4-HTP自组装单分子膜电极（4-HTP SAM/Au）进行了原位表征,采用Randles等效电路对阻抗复平面图进行模拟,确定该电极体系的等效电路以及电化学参数,通过电荷传递电阻Rct与组装时间的关系,给出了4-HTP SAM在金电极表面的组装动力学曲线.结果表明,电子传递电阻（Rct）随自组装时间的延长而迅速减小,证明4-HTP SAM是一种导电膜,当自组装时间达到120 min后,Rct不再变化,4-HTP SAM达到组装平衡状态.研究结果对SAMs的制备具有一定指导意义,在生物传感器的研究中具有应用前景.