Study on hydrogen ion-selective solid contact electrodes based on decamethylcyclopentasiloxane

摘要

Hydrogen ion-selective solid contact electrode based on decamethylcyclopentasiloxane (DMCS) as ionophore was fabricated. The membrane solution was prepared by mixing DMCS, polyvinyl chloride (PVC), potassium tetrakis p-chlorophenyl borate (KTpClPB) and various plasticizers. The best performance was obtained with the sensor based on NPOE (o-nitrophenyl octyl ether) and the conducting polymer layer of poly(pyrrole), doped with NaClO_4. The electrode exhibited Nernstian-response in the range of pH 1.9-9.8 with a slope of 57.6 ± 0.2mV per decade and fast response time within 15 s. This electrode showed good selectivity and was successfully used as an indicator electrode in the potentiometric titration.