Fabrication of coated graphite electrode for the selective determination of europium (III) ions.
Preliminary complexation study showed that two ligands (ionophores) (2-((2-phenyl-2-(pyridin-2-yl)hydazono)methyl)pyridine) [L1], (2-((2-phenyl-2-(pyridin-2-yl)hydazono) methyl)phenol) [L2] can act as europium selective electrode. Europium selective coated graphite electrodes (CGE) were prepared by using ligands [L1] and [L2] and their potentiometric characteristics were determined. Membranes having different compositions of poly(vinylchloride) (PVC), the different plasticizers, anionic additives and ionophores were coated onto the graphite surface. The potential response measurements showed that the best performance was exhibited by the proposed CGE. This electrode had the widest working concentration range, Nernstian slope and fast response times of 10s. The selectivity studies showed that this electrode have higher selectivity towards Eu(3+) over a large number of cations. Furthermore, the electrode generated constant potentials in the pH range 2.7-9.0. This electrode can be used to quantify europium in soil, binary mixtures and also used as an indicator electrode in the potentiometric titration of Eu(3+) with EDTA. The proposed electrode was also successfully applied to the determination of fluoride ions in real samples.
Department of Chemistry, Indian Institute of Technology-Roorkee, Roorkee 247667, India.
Anjali
A
Upadhyay
Ashok Kumar
AK
Singh
Koteswara Rao
KR
Bandi
A K
AK
Jain
D004492:Edetic Acid / Q000737:chemistry; D004566:Electrodes; D004785:Environmental Pollutants / Q000032:analysis*; D005063:Europium / Q000032:analysis*; D005459:Fluorides / Q000032:analysis*; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007476:Ionophores / Q000737:chemistry; D008024:Ligands; D010968:Plasticizers; D011143:Polyvinyl Chloride; D011199:Potentiometry / Q000379:methods; D011725:Pyridines / Q000737:chemistry; D012680:Sensitivity and Specificity; D012987:Soil / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry
D004785:Environmental Pollutants; D007476:Ionophores; D008024:Ligands; D010968:Plasticizers; D011725:Pyridines; D012987:Soil; D012996:Solutions; D005063:Europium; D006108:Graphite; D011143:Polyvinyl Chloride; D004492:Edetic Acid; D005459:Fluorides
Coated graphite electrode; Eu(3+) selective electrodes; Ion selective electrode; Potentiometric titration