Perovskite-Type Oxide-Based Electrode: A New Sensor for Hydrogen-Phosphate Ion

Abstract

A perovskite‐type oxide‐based electrode showed good properties of amperometric sensing to hydrogen‐phosphate ion. The anodic current of carbon‐based electrodes loaded with La‐Co‐based perovskite‐type oxide, the sensing signal, increased with increasing concentration of hydrogen‐phosphate ion at +0.85 to + 1.0 V vs. a saturated calomel electrode. The carbon electrode loaded with showed remarkable selectivity to among the examined anions of , , , , , , , and , although it received serious interference from . The use of a thin film electrode of perovskite‐type oxide drastically improved amperometric sensing to hydrogen‐phosphate ion. The thin film sensor device responded to at concentrations between and , and the 90% response time was as short as ca. 5 min or ca. 10 s at the low or high concentration range of hydrogen‐phosphate ion, respectively. The thin film sensor device showed the highest selectivity to among the examined anions. © 2000 The Electrochemical Society. All rights reserved.