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Abstract

The electrochemistry of (TPP)Co in presence of pyridine was investigated in dichloroethane solution by cyclic voltammetry. Upon the addition of pyridine to the solution, two reduction peaks of Co(Ⅲ)/Co(Ⅱ) at 0.25 and -0.40 V (SCE) were observed. It was infered that the peaks were belong to the reductions of the complex compounds with one and two axial pyridine, (TPP)Co(Ⅲ)(Py) and (TPP)Co(Ⅲ)(Py)2. Even though the mole ratio of added pyridine was less than 1 the reduction of Co(Ⅲ)/Co(Ⅱ) still mainly occured at -0.40 V, which evidently resulted from pyridine adsorption on the electrodes. Besides, it was observed that the reduction peak of Co(Ⅱ)/Co(Ⅰ) was shifted to -1.20 V (SCE) with large amount of added pyridine. The new reduction peak could be attributed to the direct reduction of the axially coordination complex (TPP)Co(Ⅱ)(Py). The mechanisms of the effect of pyridine on the electrochemical redox behaviours of (TPP)Co were given.

Publication Date

1997-11-28

Online Available Date

1997-11-28

Revised Date

1997-11-28

Received Date

1997-11-28

References

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