The influence of 4-mercaptopyridine layer instability on rapid electron transfer reaction

This paper presents studies on the influence of the instability of the 4-mercaptopyridine (pyS) layer adsorbed on polycrystalline gold surface (Au/pyS) on rapid electron transfer reaction. Voltammetric and impedance experiments were performed using Fe(CN)63- as the electrochemical probe molecule. The morphology of the layer was assessed by the atomic force microscopy (AFM) technique using gold (1 1 1) modified with the pyS. The techniques used in this work presented a qualitatively agreement concerning the instability of the pyS layer. The electrochemical results showed that instability of the pyS layer leads to an increase on rapid electron transfer reaction of the probe molecule. AFM images showed that the instability of the pyS layer leads to the arisen of defects on layer and an increase in the roughness layer.