Synthesis, Characterization and Analytical Applications of Novel Potentiometric Sensor Based on Chromium(III)Boratotungstophosphate

Abstract

Ion selective electrode based on chromium(III) boratotungstophosphate was successfully fabricated for the detection of Hg(II) ions. The characterization of electroactive material has been done with FTIR, SEM, EDS and X-Ray diffraction studies. Polymeric membranes containing different composition of electroactive material and epoxy resin as binder were prepared. The best performance was shown by the electrode with composition having 40 % electroactive material and 60 % epoxy resin. A reasonably short response time of 6 s was shown together with a life of six months without any divergence in potential. The sensor possessed a near Nernstian slope of 25 ± 0.8 mV decade-1 over a wide linear range of 1.0 × 10-1 M − 1.0 × 10-6 M Hg(II) ions. The electrode worked satisfactorily in the partially nonaqueous medium also. The working pH range of the sensor was found to be 2.43-8.0. Analytical applicability of membrane sensor was evaluated by using it as an indicator electrode for analysis of Hg(II) ions in different water samples procured from sea and canal waters. The proposed electrode displayed good selectivity for Hg(II) in the presence of some transition metal(II) ions and lanthanide(III) ions.