Lithium Ion-Selective Electrodes Based on, 1, 10-Phenanthroline Derivatives

Abstract

The preparation of 1, 10-phenanthroline derivatives and 4, 7-diphenyl-1, 10-phenanthroline derivatives as neutral carriers for ion-selective electrodes and the properties of the title electrodes are described in detail. A log K^Pot_{Li, Na} value of -3.1 was obtained for a Li⁺-selective PVC membrane electrode based on 2, 9-dibutyl-1, 10-phenanthroline. This value is superior to those reported so far. The electrodes also showed excellent selectivity coefficients for Li⁺ relative to K⁺, Mg²⁺, and Ca²⁺ The effects of substituents at the 2- and 9- positions of the carriers on the selectivity are discussed.