Modified carbon paste electrode with ionic liquid and SiO2 nanoparticles for potentiometric determination of Copper(II) ions in real samples

1,5 Diphenyl carbazone (DPC) was used as a chemical modifier for design carbon paste electrode of copper ion. A chemically modified carbon paste electrode with ionic liquid and SiO2 nanoprticles was prepared and used as a sensor for Cu2+ ion. The ionic liquid and SiO2 nanoparticles were used in the composition of the carbon paste to improve conductivity and transduction of chemical signal to electrical signal. The construction, performance, and applications of copper carbon paste electrode are described. The electrode displays a linear log [ Cu2+] versus EMF response over a wide concentration range of 1.0x10(-1)to 1.0x10(-6)M with Nernstian slope of 29.76 +/- 0.35mV/ decade with limit of detection 3.2x10- 7 over the pH range 3.8- 7.8. The electrode exhibit a Nernstian slope of 29.76 +/- 0.25mV per decade for Cu2+ ion over a wide concentration range from 1.0x10(-1)to1.0x10(- 6)M. The electrode has a fast response time (< 6 s), a satisfactory reproducibility and relatively long life time. The proposed sensor shows a good selectivity toward Cu2+ ion in comparison to other common cations and the working pH range was7.0- 11. These electrode have been successfully applied for the determination of Cu2+ ions content in various real samples.