All-solid-state hydrogen sensing microelectrodes based on novel PPy[3,3′-Co(1,2-C2B9H11)2] as a solid internal contact

Planar all-solid-state hydrogen sensing microelectrodes have been constructed and investigated. A novel conductive polymer, polypyrrole (PPy) doped with cobaltabis(dicarbollide) ions ([3,3′-Co(1,2-C2B9H11)2]−), thin film was galvanostatically grown over a solid substrate (Pt) and acted as an internal solid contact layer between the solid surface (Pt) and the polymeric sensitive membrane. The potentiometric response characteristics of this new kind of microelectrode based on tri-n-dodecylamine (TDDA) ionophore were evaluated. They exhibited excellent selectivity for the primary ion and a linear response over the pH range 3.5–11.0 with a slope of 52 ± 2 mV decade− 1. The selectivity properties have been examined. The results obtained were comparable to that of a conventional ion-selective electrode (ISE) based on the same ionophore.