Study of potentiodynamic polymerization conditions of perinone polymer and their influence on sensor performance: new...

The use of perinone polymers as an intermediate layer in solid-contact ion-selective electrodes is a new area of application for these materials. These polymers are applied to the surface of the substrate electrode by electropolymerization. This paper presents a study on the potentiodynamic polymerization of perinone polymer, focusing on selecting the most favorable conditions and increasing the universality of the process. The effects of the number of polymerization cycles, the potential range, and the use of different electrolyte salts were analyzed. Initial tests showed that electrodes modified with perinone polymer applied in 5 cycles had unsatisfactory electrical properties, while 10 cycles provided much better performance, such as higher electrical capacitance and lower resistance. The optimum potential range was narrowed to 0-1.45 V, allowing high performance while reducing the process time. In the next step, the influence of various salts (chloride and hexafluorophosphate salts) as primary electrolytes was tested. From the 12 salts tested, four hexafluorophosphate salts with the following cations: tetrabutylammonium, 1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, and 1-hexyl-3-butylimidazolium, provided efficient PPer layers, which were used for further electrochemical analysis. The PPer layer-modified potassium electrode exhibited high sensitivity (58.90 ± 0.11 mV/decade), a wide range of linearity (1 × 10^- 1 - 5 × 10^- 6 M), and a low detection limit. A positive result of the water layer test was also obtained - the potential drift was extremely low for the modified electrodes (3.2-6.1 × 10^-5 mV/s). The obtained results indicate that selecting the most favorable polymerization conditions increased the universality of the process and enabled the preparation of electrodes with significantly better electrochemical properties compared to unmodified GCE electrodes.