Development and Application of a Potentiometric Hg2+-Imprinted Polymer/graphitic Carbon Nitride/Carbon Paste Electrode

A potentiometric electrode was developed for Hg2+ through modifying a carbon paste electrode using Hg2+-ion imprinted polymer and graphitic carbon nitride (g-C3N4). The optimal composition of the developed electrode (Hg2+-IP/g-C3N4/ CPE) was observed for a composition of Hg2+-IP: g-C3N4 nano-sheets: nujol oil: graphite powder at a weight ratio of 5:5:25:65 (w:w). The sensor’s response had a Nernstian slope (30.5±0.4 mVdecade-1 and a short response time of around 10 s, and produced a linear response over a broad concentration window extending from 1.0×10−9 M to 1.0×10−3 M and a detection limit of 4.3×10−10 M was determined for it. Effects of the presence of Na+, K+, Ag+, Ca2+, Mg2+, Cu2+, Ni2+, Zn2+, Cd2+ and Co2+ in the test solution, on the response of Hg2+-IP/g-C3N4/ CPE was evaluated and the sensor was found to be high selectivity. The developed sensor was also evaluated through analyzing the concentration of Hg2+ in different water samples.