Detection of Terbium(III) Ions by a Selective Electrode Based on a Hydrazinecarboxamide Derivative

摘要

Solution study showed that N-phenyl-2-(phenylcarbamothioyl) hydrazinecarboxamide (PPH) has atendency to selectively bind with Tb(III) ions as compared to other tested ions and the data led us tohypothsize that the ligand can be used as an ionophore in construction of terbium ion selectiveelectrodes. Electrode composed of 30% PVC, 65% a solvent mediator (DBP), 3% (PPH) and 2% of anionic additive (i.e. NaTPB) were found to show the best potentiometric response characteristics with a Nernstian potential response of 19.7 mV per decade over the concentration range 1.010 to 1.010-1 mol L . The response time of the electrodes were found to be as short as ~10 s and and it was found towork well in the pH range of 2.8-8.5 and was applicable for at least 2 months. The proposed membrane3+ sensor shows excellently discriminates Tb ions as compared to several alkali, alkaline earth,transition and heavy metal ion.