关键词: 聚次甲基蓝, 现场光谱电化学, 旋转环-盘电极, XPS, 交流阻抗

Abstract: The in situ spectroelectrochemical experiment shows that an absorption peak at 580.5 nm attributable to poly(methylene blue) grows slowly at the begin ning of the electrolysis of methylene blue, and then this peak grows more quickl y. The visible spectra prove that there are two absorption peaks at 580.5 and 6 90.2 nm respectively for the mixture solution after electrolysis. The former on e indicates that poly(methylene blue)polymerized on the ITO electrode is partly soluble; the latter one is attributed to a watersoluble polymer since it compl etely dissolves in the aqueous solution. The result from the rotating ringdisk electrode identifies that an intermediate is produced at the disk electrode, wh ich is collected at the ring electrode. The ring current increases with decreasi ng the ring potential and with increasing the rotation rate. Thus, the intermedi ate is a species carrying a positive charge and not too stable.The result from t he XPS experiment shows that the anions can be doped into poly(methylene blue) f ilm and dedoped from it during oxidation and reduction processes. The results fr om the impedance experiment indicate that the charge transfer impedance of poly( methylene blue) decreases with decreasing potential.

Key words: Poly(methylene blue), In situ spectroelectrochemistry, RRDE, XPS, 　Impedancespectra