Functionalized PEDOT:PSS based sensor array for determination of metallic ions in smart agriculture

A stable supply of metallic elements such as potassium, calcium, and magnesium is indispensable for plant growth. Therefore, qualitative and quantitative detection of metallic ions in aquaponic environments has been of interest. Impedimetric sensors are attractive for ease of preparation, low cost, and high sensitivity. In this paper, we present an impedimetric interdigitated electrode array for the determination of K(I), Ca(II), and Mg(II) based on functionalized PEDOT:PSS. We optimize the parameters for sensor fabrication, demonstrate the impedance characteristics and ion response properties of functionalized PEDOT:PSS, and use a hybrid algorithm to realize the classification of the array signal. It was found that the heating temperature and the number of coating layers significantly affect the conductivity of the sensor. We made the calibration curves of PEDOT:PSS/CuPc towards the ions at the concentration range of 1 – 10 mM. The different functionalized PEDOT:PSS exhibited verified selectivity for metallic ions. The PCA-SVM algorithm was employed as a classification model to identify metallic ions in liquids effectively