Differential pulse stripping voltammetry of moderately hydrophobic ions based on hydrophobic ionic liquid membranes supported on the Ag/AgCl electrode

Differential pulse stripping voltammetry (DPSV) based on the ion transfer across the hydrophobic ionic liquid and an aqueous sample solution has been achieved for the analysis of moderately hydrophobic ions. The ionic liquid membrane was made of the double layers of gelled trioctylmethylammonium bis(nona-fluorobutanesulfonyl)amide ([TOMA+][C4C4N−]), a hydrophobic ionic liquid. The first [TOMA+][C4C4N−] layer containing trioctylmethylammonium chloride (TOMACl) was in contact with a AgCl layer of a planar Ag/AgCl electrode, and the second [TOMA+][C4C4N−] layer without containing TOMACl was in contact with a sample solution. The linearity between the DPSV peak and the concentration of analytes, tetrapropylammonium and tridecafluoroheptanoate, was found between 5 μmol dm−3 and 200 μmol dm−3 of these ions.