Synthesis of Single-Walled Carbon Nanotubes Cerium(IV) Phosphate Composite Cation Exchanger: Ion Exchange Studies and Its Application as Ion-Selective Membrane Electrode for Determination of Cd(II) Ions

摘要

Single-walled carbon nanotubes cerium(IV) phosphate composite cation exchanger was synthesized using sol-gel method. The ion-exchange properties such as elution concentration, elution behavior and effect of temperature on ion exchange capacity were studied. The composite cation exchange material showed an ion-exchange capacity (IEC) of 1.64 meq dry g(-1) of ion exchanger. The distribution studies revealed that the composite cation-exchanger is highly selective for Cd(II) ions. The material was used as an electroactive component for the construction of a cadmium ion-selective membrane electrode. The membrane electrode showed a Nernstian response for Cd(II) ions over a wide concentration range of 1 x 10(-7) -1 x 10(-1) M with a sub-Nernstian slope of 27.429 mV per decade change in concentration of cadmium ions. The limit of detection was found to be 1 x 10(-7) M. It possessed a fast response time 10 s and can be utilized for 130 days without any considerable divergence in response potential. The practical utility of membrane electrode was demonstrated by employing as an indicator electrode for the potentiometric titration of Cd(II) with ethylenediamine tetra acetic acid, disodium salt (EDTA). (C) 2015 Society of Plastics Engineers