Determination of Cd2+ in aqueous solution using polyindole–Ce(IV) vanadophosphate conductive nanocomposite ion-selective membrane electrode

Abstract

In the present study an organic–inorganic nanocomposite ion exchanger Polyindole-Ce(IV) vanadophosphate (PIn-CVP) was synthesized via sol-gel process showing excellent ion exchange capacity (IEC‒1.90 meqg−1). The material was characterized by SEM, TEM, XRD, FTIR, and TGA. A heterogeneous ion exchange membrane of PIn-CVP (IEC‒0.90 meqg−1) was also prepared by solution casting method. PIn-CVP shows high electrical conductivity (5.5 × 10−2 S cm−1) and it is stable up to 120 °C under ambient conditions. Cd2+ selective membrane electrode was fabricated and its linear working range (3.98 × 10−7 M to 1.0 × 10−1 M), response time (25 s), Nerstian slope 25.00 mV dec−1 and working pH range (4–7) were calculated. It was employed as an indicator electrode in the potentiometric titration of Cd2+.