All-Printed Flexible Electrochemical Sensor Based on Polyaniline Electronic Ink for Copper (II), Lead (II) and Mercury (II) Ion Determination

The electrochemical determination of copper (II), lead (II) and mercury (II) ions has been studied and analyzed in this paper. Preparation of polyaniline functional ink by electronic ink technology was proposed. Screen-printed carbon electrode (SPCE) modified by ethylene diamine tetraacetic acid @ polyaniline/multi-walled carbon nanotube nanocomposite structure was used as an electrochemical sensor by all-printed technology to selectively detect copper, lead and mercury ions. The improved electrode is a great improvement in process simplicity and practicability. Square-wave voltammetry was used to detect the concentration of copper, lead and mercury ions, and the selectivity, sensitivity, reproducibility and stability of the ions were also studied. The detection results show that the modified SPCE electrode has high selectivity, sensitivity and reproducibility. The detection limit of copper ions was determined as 55.4 pM, that of lead ions was 22 pM, and that of mercury ions was 17.8 pM.