A novel carbon paste electrode for the potentiometric analysis of Cu2+ in water and soil samples

In this project, zinc oxide nanoparticle loaded on activated carbon (ZnO-NP-AC) has been synthesized and characterized by different techniques including XRD and SEM. Then A new simple, reliable, rapid and reproducible carbon paste electrode (CPE) for copper ions based on a new Schiff’ base as carrier was prepared and fully characterized in terms of composition, usable pH range and response time. ZnO-NP-AC was added to the electrode before pasting. The influence of variables including pH, membrane ingredients was optimized and set as graphite powder: carrier (ligand): sodium tetraphenylborate (NaTPB): amount of ZnO-NP-AC: Nujol with the mass (g) ratio of 0.125: 0.01: 0.003: 0.03: 0.05. At optimum values of all variables the electrode response is linear in the concentration range of 5.0×10−7 to 1.0×10−1 mol L-1 with detection limit 1.5×10−7 mol L-1 with nernstian slop of 30.3 mV/decade over the pH range of 2.0-5.0. The proposed sensor reveals good selectivity toward Cu2+ ion with respect to many alkali, alkaline earth, transition and heavy metal ions. It was applied to the determination of Cu2+ in water and soil samples.

A novel carbon paste electrode for the potentiometric analysis of Cu2+ in water and soil samples Keywords:

Carbon paste electrode , Copper selective electrode , Potentiometric sensor , Zinc oxide nanoparticles