Sensing Element Based on a New Nanoparticle to Develop a Carbon past Electrode for Highly Sensitive Determination of Ag+ in Aqueous Solutions

Sensing Element Based on a New Nanoparticle to Develop a Carbon past Electrode for Highly Sensitive Determination of Ag+ in Aqueous Solutions

Here, we report the use of newly synthesized amine-functionalized silica nanoparticles (SNP-NH2s), based on multi-walled carbon nanotubes (MWCNTs), as heart of a sensing element for construction a new carbon paste electrode. Then, the modified electrode was successfully applied in Ag+ ion quantification by potentiometric method. The results showed that the modified electrode exhibits a Nernstian slope of -59.8 (±0.2) mV/decade for Ag+ ion in aqueous solution. The potential response of electrode covers a wide concentration range from 1.2×10-1 to 7.0×10-9 M of Ag+. The detection limit of the system was found 5.0×10-9 M while it is independent of the pH from 3.5 to 8.0 and shows a quick response time (45 s) with lifetime of about 2 months. The proposed electrode was successfully used as an indicator sensor in determination silver ion in waste-waters of photographic and radiological films.