硝基化合物的吸附伏安法研究 Ⅰ.5-硝基-1,10-邻菲咯啉的吸附伏安特性

Studies on the Adsorption Voltammetry of Nitro Compounds I. The Adsorption Voltammetry of 5-Nitro-1, 10-Phenanthroline

吸附伏安法是一种高灵敏度的简单的电分析化学方法。对不可逆过程的线性变势技术,灵敏度比无吸附时大3—4个数量级。利用配合物的吸附,可以测定痕量无机离子。配位体的吸附伏安特性是一个十分重要的因素。5-硝基-1,10-邻菲咯啉(Phen-NO_2)是一种常用的配位体,它的吸附伏安特性还未见报道。本文用线性扫描技术对氨性溶液中,低浓度Phen-NO_2的吸附伏安特性进行了研究。

The behaviour of the 5-nitro-1, 10-phenanthroline (phen-NO_2) at the hanging mercury drop electrode (HMDE) has been investigated by linear sweep adsorption voltammetry in detail. It is shown that under the condition of potential ranging from -0.1--0.2V (vs. SCE), phen-NO_2 can be adsorbed on the surface of HMDE very well. When the potential is scanned in the negative direction a peak is obtained. The peak potential is -0.38 V for v=100m V/s. The experimental data for adsorption amount and peak current agree with the theoretical prediction. The reduction of o-phen-NO_2 at HMDE is irreversible. The number of the electrons transferred in the overall reaction is 4. The number of the transferred electrons and symmetry coefficient in the rate determining step are 3 and 0.42, respectively.