化学学报 ›› 1987, Vol. 45 ›› Issue (10): 971-976. 上一篇    下一篇

研究论文

钴(II)-丁二酮肟体系极谱催化波的机理研究

倪亚明;李玲;周纯;高小霞   

  1. 北京大学化学系
  • 发布日期:1987-10-15

Study on the polarographic catalytic wave of the system cobalt(II)-dimethylglyoxime

NI YAMING;LI LING;ZHOU CHUN;GAO XIAOXIA   

  • Published:1987-10-15

本文研究了钴(II)-丁二酮肟(DMG)在氨性底液(pH9)中极谱催化波的机理.用线性扫描伏安法,循环伏安法和阳极溶出法等方法证明,这催化波的形成是由于吸附在汞电极上的钴(II)-丁二酮肟螯合物不可逆地还原到零价的"活性钴",同时在电极表面的"活性钴"又催化了丁二酮肟的还原.

关键词: 阳极溶出伏安法, 极谱分析, 钴络合物, 二甲基乙二肟, 电化学分析, 催化波, 循环伏安法

In the Co(II)-dimethylglyoxime (HDMG)-NH3-NH4Cl (pH 9) system, Co(II)(DMG)2 in the solution is adsorbed on the Hg electrode surface and exhibited a highly sensitive polarog. catalytic peak. The characteristics of this catalytic current was investigated by linear potential sweep voltammetry, cyclic voltammetry and stripping anal. The experimental evidences showed that a 0-valence "active cobalt" was formed during the irreversible reduction of Co(II)(DMG)2 and simultaneously DMG is catalytically reduced by the "active cobalt". The mechanism of this system with the conflicting explanations of a catalytic H wave or only an adsorptive complex wave is discussed.

Key words: ANODIC-STRIPPING VOLTAMMETRID METHOD, POLAROGRAPHIC ANALYSIS, COBALT COMPLEX, DIMETHYL GLYOXINE, ELECTROCHEMICAL ANALYSIS, CATALYTIC WAVE, CYCLOVOLTAMGRAPH

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