长寿命高选择性液膜碘离子电极的研究

Studies on Liquid Membrane Iodide Selective Electrode with Long Lifetime and High Selectivity

合成了ＰＶＣ－双硫腙－Ｈｇ（Ⅱ）载体．以该载体物质制备了高选择性碘离子电极，其选择性次序为：Ｉ－ＣｌＯ－４＞ＳＣＮ－＞ＮＯ－２Ｓａｌ－～Ｂｒ－＞ＮＯ－３＞Ｃｌ－．电极对碘离子的线性响应范围为１×１０－３～５×１０－７ｍｏｌ／Ｌ，检测下限为２×１０－７ｍｏｌ／Ｌ，斜率为（５９±１）ｍＶ／ｄｅｃａｄｅ（１６℃）．并研究了电极的响应机理，表明系碘离子与载体中金属汞原子直接作用．将该电极应用于食盐中碘的测定。

PVC\|DZT\|Hg() compound was synthesized and used to prepare a high selectivity iodide electrode. The selectivity order of the electrode is I\+-ClO\+-\-4>SCN\+->NO\+-\-2\{Sal\+-\}Br\+->NO\+-\-3>Cl\+-. The electrode has a linear response to iodide from 110\+\{-3\} to \{510\+\{-7\}\} mol/L with a detection limit of 210\+\{-7\} mol/L and a slope of (591) mV/decade(16). The response mechanism of the electrode was investigated by spectroscopic techniques. It was demonstrated that iodide anion acts with Hg in the carrier. The electrode was satisfyingly used for the determination of iodine content in the salts from different markets.