Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
741732 | Sensors and Actuators B: Chemical | 2007 | 6 Pages |
The potentiometric pH response of gold electrodes, modified with polydiphenylamine (PDPA) films was studied. These were obtained by electropolymerization of saturated diphenylamine in 3.7 M HClO4 solutions by cycling the working electrode potential between −0.10 and 0.65 V versus saturated calomel electrode (SCE). The PDPA modified electrodes were subjected to a conditioning treatment consisting of a sequence of electrochemical procedures performed in 1 M H2SO4 solutions. This treatment improves the linearity and sensitivity of the pH response and enlarges to 0 ≤ pH ≤ 11 the measuring range. The potential versus pH slope is 0.041 V/pH unit; this value is due to the fact that the conditioning treatment produces an effective pK distribution that is much wider that in the as made PDPA films.