Ionic liquid salt bridge based on tributyl(2-methoxyethyl)phosphonium bis(pentafluoroethanesulfonyl)amide for stable liquid junction potentials in highly diluted aqueous electrolyte solutions

Abstract: A moderately hydrophobic ionic liquid, tributyl(2-methoxyethyl)phosphonium bis(pentafluoroethanesulfonyl)amide ([TBMOEP+][C2C2N−]), shows a very stable liquid junction potential upon contact with an aqueous solution whose ionic strength is as low as 1μmoldm−3. The stability with the maximum excursion of the potential within ±0.5mV for 30min is very promising for accurate determination of pH and other single ion activities potentiometrically. [ABSTRACT FROM AUTHOR]