四苯硼酸钾衍生物为载体的锂离子选择性电极

Lithium Ion-Selective Polymeric Membrane Electrode Based on Potassium Tetraphenylborate Derivatives

合成了3种四苯硼酸钾衍生物，并以此作载体研制了PVC膜锂离子选择性电极。其中四（对－甲氧基苯基）硼酸钾作载体的电极对锂离子响应的线性范围为5．2×10－5～1．0×10－1mol／L；检测下限1．4×10－5mol／L；斜率55．6±0．3mV／pLi（20℃），电极具有较好的稳定性、重视性。研究了这些载体溶剂聚合膜的Li＋离子的传输实验，对含四（对－甲氧基苯基）硼酸钾载体的膜传输离子的次序为Li＋＞Na＋＞K＋，其次序与载体膜响应离子的选择性次序一致。电极用于碳酸锂片剂中锂含量测定，获得满意的结果。

This paper dcscribed the preparation of lithium ion selective electrodes based on potassium tetraphenylborate derivatives synthesized in our laboratory. The electrode doped with potassium tetra (p-methoxyphenyl)borate shows a near-Nernst potentiometric response for 5. 2×10-5～1. 0×10－1 mol/L Li+ with a detection limit of 1. 4 ×10-5 mol/L and a slope of 55. 6±0. 3 mV/p Li+ (at 20℃ ). The electrode had the advantages of good stability and reproducibility. Transfer behavior of cation ions through an organic phase was investigated by means of the polymeric rnembrane transpcrt experiment. The mass transfer rates of the tested ion facilitated by potassium tetra (p-methoxyphenyl)borate were determined ar`d the following sequence was found; Li+>Na+>K+. This sequence was in good agreement with selectivity sequence of the corresponding species.