Potentiometric Performance of 3-hydroxy-N•-[(2-hydroxyphenyl)methylene]-2-naphtho- hydrazide Ionophore as a Silver Sensing Material

A polyvinyl chloride(PVC)based membran sensor for silver ions was prepared by employing 3-hydroxy-N•-[(2-hydroxyphenyl)methylene]-2-naphtho- hydrazide (L). as anionophore, Among the three different plasticizers 2-NPOE, DBP and BES, 2-NPOE is the best plasticizer (due to its high dielectric constant makes the ionophore in free movement and fast exchange in complexation and decomplexation between ionophore and silver ions).The plasticized membrane sensor exhibits a Nernstian response for Ag(I) over wide concentration range (10-4to10-1M)with limit of detection as low 3×10- 5M.It has fast reponse time (<10s) and can be used for 4 months. The response of the proposed sensor is independed of pH between 2.5-8.5.The calibration curve has a slope 56 mVdecade-1. The characteristics were studied the electrode with the ratio PVC:2-NPOE:L=33%:63%:4%.Tetra hydro furane(THF)was interface solvent. The proposed sensor is advancement over the reported electrodes.The high selectivity of the proposed sensor made it possible to determine the silver in different real samples and also used as an indicator electrode in potentiometric titration of different anions with silver solution. . In particular, ion-selective electrodes are the most important analytical tools for detection of the target ions.

کلیدواژه ها:

polyvinyl chloride ، potentiometric titration ، target ions ، Electrochemical sensor ، 3-hydroxy-N•-[(2-hydroxyphenyl)methylene]-2-naphtho- hydrazide