pH sensor based on deposited film of lead oxide on aluminum substrate electrode

Two modified electrodes were fabricated by deposition of thin films of alpha-PbO2 and beta-PbO2 on aluminum substrate electrodes. Both electrodes exhibit potentiometric response to the hydrogen ion concentration and, consequently, can be used as pH sensors. The potentiometric responses of the modified electrodes were close to the theoretical slope of Nerustian response and comparable with glass electrodes. The electrochemical properties and stability of the constructed electrode were investigated. The possibility of the pH sensor for using in flow injection analysis (FIA) was also studied, and the optimum conditions were obtained. (C) 2002 Published by Elsevier Science B.V.