An ion-selective potentiometric sensor for hexafluoroarsenate

Ion-selective potentiometric sensors (ion selective electrodes, ISEs) based on tetradecylphosphonium hexafluoroarsenate are developed for the determination of AsF6− ions. Their main parameters, such as selectivity, linearity range of response, detection limit, and also the effect of pH on the readings of electrodes are evaluated. The developed electrode demonstrated high selectivity to the AsF6− acido-complex in the presence of various anions. The detection limit goes up with increasing concentration of HF; for fluoridefree neat solutions of LiAsF6, it is 3 × 10−7, pAsF6 = 6.52; at the concentrations of HF 0.1 and 4 M, it is 1.5 × 10−6 M, pAsF6 = 5.82, and 7 × 10−6 M, pAsF6 = 5.15, respectively.