LAUSR

An electrochemical method was used to prepare polyaniline (PANI) with hydrochloric acid as a dopant. This electroactive material was fabricated using electrically modified carbon coated Teflon electrodes with an area of 0.64 cm2 in 1 M HCl. PANI was electrochemically synthesized using cyclic voltammetry (CV) with a variable number of cycles, scan rates, and step sizes at potentials ranging from − 0.2 V to 0.8 V. Fabricated samples were tested using different electrochemical techniques including CV, differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The DPV and EIS measurements indicate a linear relationship between both the current peak and the charge transfer resistance (Rct) and pH. These measurements showed that the prepared electrochemical device can be used as a sensor for pH. Optimum preparation parameters were 30 cycles, 50 mV/s scan rate and 2 mV step size. A linear relationship between oxidation current and pH of the solution with a correlation coefficient of 0.97 in the range of 1–5 makes PANI a candidate to be used as a pH sensor.