研究了在4-氯苯酚(简称氯酚)电化学稳定窗口内氯酚对Ti基IrO2电极在酸性水溶液中电化学活性的影响.循环伏安(cv)与电化学阻抗谱(EIS)测试均显示,几乎在整个氯酚的电化学稳定电位区间内,氯酚对氧化物电极均起到活化作用.以金属Ir电极为对比试样的测试结果却显示,由于氯酚易于在金属表面吸附,氯酚在其电化学稳定窗口内对金属电极的活性产生抑制作用.基于氯酚对上述两类电极电化学行为影响的差异,提出活性氧化物自身在上述电位区间内发生从低价态到高价态的转变,进而用于氧化去除吸附在电极表面的有机分子,可能是氯酚对IrO2电极造成活化的主要原因.
The effect of 4-chlorophenol (4-CP) on the electrochemical activity of Ti-based IrO2 electrodes in acidic aqueous solutions was investigated within the electrochemical window for 4-CP. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements both indicated that the existence of 4-CP in solution resulted in the activation of the IrO2 electrode in the electrochemical window. However, the testing results at metallic Ir electrode showed that the electrode activity was inhibited by 4-CP because of its adsorption onto the metal surface. A possible mechanism is proposed based on the influence of 4-CP on the electrochemical activities of these two electrode materials. The activation of IrO2 is believed to be related to its ease of transition from lower-valent to higher-valent oxides in the electrochemical window. The later oxides can be chemically oxidized and can remove organic molecules that are adsorbed onto the oxide electrode surface.