用微电极和薄层循环伏安(CV)技术研究了Br-对四苯基钴卟啉((TPP)Co)在1,2_二氯乙烷(DCE)中电化学行为的影响.发现在较高电位下,两个Br-轴向配位的(TPP)Co(II)(Br-)2其一个Br-发生脱落表现出(TPP)Co(II)(Br-)的行为特征,这被证明是Br-的氧化所致.证明了(TPP)Co(II)(Br-)在约0.12V(SCE)处还原,而(TPP)Co(II)(Br-)2则在大约Co(I)/Co(I)还原过程出现的更负的电位处发生还原
The effect of Br - anion on electrochemical behavior of (TPP)Co was investigated in 1,2 dichloroethane solution by microelectrode and thin layer cyclic voltammetry technique. It was found that the axially coordination of one Br - anion to (TPP)Co(Ⅲ)(Br -) 2 shifts the potential of porphyrin system to more positive value. The reduction peak of 0.12 V(vs.SCE) is attributed to the reduction of (TPP)Co(Ⅲ)(Br -). It is also postulated that the reduction of (TPP)Co(Ⅲ)(Br -) 2 occurred at a more negative potential where the reduction of the Co(Ⅱ)/Co(Ⅰ) process happened.
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